1
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Zheng D, Duan J, Wu Y, Dong W. Mechanistic insight into the photoconversion of losartan potassium mediated by different types of microplastics. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135143. [PMID: 39018600 DOI: 10.1016/j.jhazmat.2024.135143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/22/2024] [Accepted: 07/06/2024] [Indexed: 07/19/2024]
Abstract
Nowadays the proliferation of microplastics (MPs) in aquatic environments and impacts on the fate of organic contaminants (OCs) has drawn sustained worldwide attention. In this study, we investigated the effects of different types and aging degrees of MPs, specifically polystyrene (PSMPs), polyethylene terephthalate (PETMPs), and polylactic acid (PLAMPs), on the photo-transformation of LSTPs. Our results revealed that the facilitation of LSTP photoconversion by PSMPs exhibited a positive linear relationship with aging degree. On the other hand, the effects of PETMPs with different oxidation levels on LSTP photoconversion were weak, while the contribution of PLAMPs decreased as aging increased. Characterizations, quenching and probing experiments showed the aging mechanisms and the generation of reactive oxygen species (ROS) converged among various MPs. Specifically, theoretical calculations, TOC and GC-MS were conducted to verify that in the PLA0-mediated systems, it was the intermediates of PLA0 that prevailed in promoting the photoconversion of LSTP. The aged PLA own have a large propensity to consume ROS, which diminished their promotion of LSTP degradation. This differd from the reactions involving PSMPs and PETMPs, where the microplastic particles themselves were the main drivers of the photoconversion process rather than intermediates.
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Affiliation(s)
- Danqing Zheng
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Jiehan Duan
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Yanlin Wu
- School of Resources and Environmental Engineering, Shanghai Polytechnic University, Shanghai 201209, China.
| | - Wenbo Dong
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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2
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Li M, Huang XL, Zhang ZY, Wang Z, Wu Z, Yang H, Shen WJ, Cheng YZ, You SL. Gd(III)-Catalyzed Regio-, Diastereo-, and Enantioselective [4 + 2] Photocycloaddition of Naphthalene Derivatives. J Am Chem Soc 2024; 146:16982-16989. [PMID: 38870424 DOI: 10.1021/jacs.4c05288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2024]
Abstract
Catalytic asymmetric dearomatization (CADA) reactions have evolved into an efficient strategy for accessing chiral polycyclic and spirocyclic scaffolds from readily available planar aromatics. Despite the significant developments, the CADA reaction of naphthalenes remains underdeveloped. Herein, we report a Gd(III)-catalyzed asymmetric dearomatization reaction of naphthalene with a chiral PyBox ligand via visible-light-enabled [4 + 2] cycloaddition. This reaction features application of a chiral Gd/PyBox complex, which regulates the reactivity and selectivity simultaneously, in excited-state catalysis. A wide range of functional groups is compatible with this protocol, giving the highly enantioenriched bridged polycycles in excellent yields (up to 96%) and selectivity (up to >20:1 chemoselectivity, >20:1 dr, >99% ee). The synthetic utility is demonstrated by a 2 mmol scale reaction, removal of directing group, and diversifications of products. Preliminary mechanistic experiments are performed to elucidate the reaction mechanism.
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Affiliation(s)
- Muzi Li
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Xu-Lun Huang
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zuo-Yu Zhang
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zhiping Wang
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Zhuo Wu
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Hui Yang
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Wen-Jie Shen
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Yuan-Zheng Cheng
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
| | - Shu-Li You
- New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China
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3
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Tian D, Shi W, Sun X, Zhao X, Yin Y, Jiang Z. Catalytic asymmetric [4 + 2] dearomative photocycloadditions of anthracene and its derivatives with alkenylazaarenes. Nat Commun 2024; 15:4563. [PMID: 38811663 PMCID: PMC11137010 DOI: 10.1038/s41467-024-48982-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/20/2024] [Indexed: 05/31/2024] Open
Abstract
Photocatalysis through energy transfer has been investigated for the facilitation of [4 + 2] cycloaddition reactions. However, the high reactivity of radical species poses a challenging obstacle to achieving enantiocontrol with chiral catalysts, as no enantioselective examples have been reported thus far. Here, we present the development of catalytic asymmetric [4 + 2] dearomative photocycloaddition involving anthracene and its derivatives with alkenylazaarenes. This accomplishment is achieved by utilizing a cooperative photosensitizer and chiral Brønsted acid catalysis platform. Importantly, this process enables the activation of anthracene substrates through energy transfer from triplet DPZ, thereby initiating a precise and stereoselective sequential transformation. The significance of our work is highlighted by the synthesis of a diverse range of pharmaceutical valuable cycloadducts incorporating attractive azaarenes, all obtained with high yields, ees, and drs. The broad substrate scope is further underscored by successful construction of all-carbon quaternary stereocenters and diverse adjacent stereocenters.
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Affiliation(s)
- Dong Tian
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan, P. R. China
| | - Wenshuo Shi
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan, P. R. China
| | - Xin Sun
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan, P. R. China.
| | - Xiaowei Zhao
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan, P. R. China
| | - Yanli Yin
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, P. R. China.
- College of Advanced Interdisciplinary Science and Technology, Henan University of Technology, Zhengzhou, Henan, P. R. China.
| | - Zhiyong Jiang
- Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Jinming Campus, Kaifeng, Henan, P. R. China.
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, P. R. China.
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4
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Zhao C, Gao R, Ma W, Li M, Li Y, Zhang Q, Guan W, Fu J. A facile synthesis of α,β-unsaturated imines via palladium-catalyzed dehydrogenation. Nat Commun 2024; 15:4329. [PMID: 38773128 PMCID: PMC11109338 DOI: 10.1038/s41467-024-48737-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 05/13/2024] [Indexed: 05/23/2024] Open
Abstract
The dehydrogenation adjacent to an electron-withdrawing group provides an efficient access to α,β-unsaturated compounds that serving as versatile synthons in organic chemistry. However, the α,β-desaturation of aliphatic imines has hitherto proven to be challenging due to easy hydrolysis and preferential dimerization. Herein, by employing a pre-fluorination and palladium-catalyzed dehydrogenation reaction sequence, the abundant simple aliphatic amides are amendable to the rapid construction of complex molecular architectures to produce α,β-unsaturated imines. Mechanistic investigations reveal a Pd(0)/Pd(II) catalytic cycle involving oxidative H-F elimination of N-fluoroamide followed by a smooth α,β-desaturation of the in-situ generated aliphatic imine intermediate. This protocol exhibits excellent functional group tolerance, and even the carbonyl groups are compatible without any competing dehydrogenation, allowing for late-stage functionalization of complex bioactive molecules. The synthetic utility of this transformation has been further demonstrated by a diversity-oriented derivatization and a concise formal synthesis of (±)-alloyohimbane.
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Affiliation(s)
- Chunyang Zhao
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Rongwan Gao
- Department of Chemistry, Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Wenxuan Ma
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Miao Li
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Yifei Li
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Qian Zhang
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Wei Guan
- Department of Chemistry, Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China.
| | - Junkai Fu
- Department of Chemistry, Jilin Province Key Laboratory of Organic Functional Molecular Design and Synthesis and Institute of Functional Material Chemistry, Northeast Normal University, Changchun, 130024, China.
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5
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Di Terlizzi L, Nicchio L, Protti S, Fagnoni M. Visible photons as ideal reagents for the activation of coloured organic compounds. Chem Soc Rev 2024; 53:4926-4975. [PMID: 38596901 DOI: 10.1039/d3cs01129a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
In recent decades, the traceless nature of visible photons has been exploited for the development of efficient synthetic strategies for the photoconversion of colourless compounds, namely, photocatalysis, chromophore activation, and the formation of an electron donor/acceptor (EDA) complex. However, the use of photoreactive coloured organic compounds is the optimal strategy to boost visible photons as ideal reagents in synthetic protocols. In view of such premises, the present review aims to provide its readership with a collection of recent photochemical strategies facilitated via direct light absorption by coloured molecules. The protocols have been classified and presented according to the nature of the intermediate/excited state achieved during the transformation.
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Affiliation(s)
- Lorenzo Di Terlizzi
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Luca Nicchio
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
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6
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Luz Tibaldi-Bollati M, Nicotra V, Oksdath-Mansilla G, García ME. Expanding Diterpene Complexity and Diversity via Photoinduced Ring Distortions. Chempluschem 2024; 89:e202300537. [PMID: 38029375 DOI: 10.1002/cplu.202300537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 11/23/2023] [Accepted: 11/29/2023] [Indexed: 12/01/2023]
Abstract
Natural products and their semi-synthetic derivatives undoubtedly constitute an important source of therapeutic agents. Their importance lies in their own origin and evolution, since they have great chemical diversity, biochemical specificity, and pharmacological properties. Currently, there is a renewed interest in the development of methodologies capable of efficiently modifying the chemical structure of these bioactive platforms. In this work, the photoderivatization of the diterpene solidagenone was performed using a complexity-to-diversity-oriented approach. By exploring [2+2]-photocycloaddition, photoinduced-hydrogen abstraction, and photoxygenation reactions, a set of solidagenone derivatives was obtained, showing different ring fusions, side chain rearrangements, and modifications of the original furan ring's substitution pattern. The derivatives obtained were characterised by NMR methodologies. To evaluate the structural diversity of the labdane-derived compounds, their physicochemical properties, structural similarity, and chemical space were analysed. These results suggest that photochemical reactions are a useful tool for performing ring distortion transformations, generating derivatives of natural compounds with wide diversity, structural complexity, and with potential biological properties.
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Affiliation(s)
- María Luz Tibaldi-Bollati
- Dpto. de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina
- Instituto Multidisciplinario de Biología Vegetal (IMBIV), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Viviana Nicotra
- Dpto. de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina
- Instituto Multidisciplinario de Biología Vegetal (IMBIV), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Gabriela Oksdath-Mansilla
- Dpto. de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina
- Instituto de Investigaciones en Físico-Química de Córdoba (INFIQC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Manuela E García
- Dpto. de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina
- Instituto Multidisciplinario de Biología Vegetal (IMBIV), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
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7
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Goti G, Manal K, Sivaguru J, Dell'Amico L. The impact of UV light on synthetic photochemistry and photocatalysis. Nat Chem 2024; 16:684-692. [PMID: 38429343 DOI: 10.1038/s41557-024-01472-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 02/08/2024] [Indexed: 03/03/2024]
Abstract
During the past 15 years, an increasing number of research groups have embraced visible-light-mediated synthetic transformations as a powerful strategy for the construction and functionalization of organic molecules. This trend has followed the advent and development of photocatalysis, which often operates under mild visible-light irradiation. Nowadays, the general perception of UV-light photochemistry is often as an out-of-fashion approach that is difficult to perform and leads to unselective reaction pathways. Here we wish to propose an alternative and more realistic point of view to the scientific community. First, we will provide an overview of the use of UV light in modern photochemistry, highlighting the pivotal role it still plays in the development of new, efficient synthetic methods. We will then show how the high levels of mechanistic understanding reached for UV-light-driven processes have been key in the implementation of the related visible-light-driven transformations.
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Affiliation(s)
- Giulio Goti
- Department of Chemical Sciences, University of Padova, Padova, Italy
| | - Kavyasree Manal
- Center for Photochemical Sciences and Department of Chemistry, Bowling Green State University, Bowling Green, OH, USA
| | - Jayaraman Sivaguru
- Center for Photochemical Sciences and Department of Chemistry, Bowling Green State University, Bowling Green, OH, USA.
| | - Luca Dell'Amico
- Department of Chemical Sciences, University of Padova, Padova, Italy.
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8
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Hai H, Qin S, Zhang Y, Liu W, Feng J, Guo H, Kühn FE, Liu Y. Visible Light-Induced Regioselective Intermolecular [2 + 2]-Cycloaddition of Alkyne and 2(1 H)-Quinolone Derivatives. J Org Chem 2024. [PMID: 38190649 DOI: 10.1021/acs.joc.3c02685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
We have developed a visible light-induced intermolecular [2 + 2]-cycloaddition reaction between alkenes and alkynes using thioxanthone and Cu(OTf)2 as cocatalysts. Various quinolin-2(1H)-ones, featuring diverse substituted groups, were successfully employed in this reaction, resulting in the synthesis of a series of 4,8b-dihydrocyclobuta[c]quinolin-3(2aH)-ones. Our methodology presents a novel synthetic approach for alkene-alkyne [2 + 2]-cycloaddition, delivering cyclobutene derivatives with exceptional regioselectivity.
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Affiliation(s)
- Hao Hai
- Academy for Engineering and Technology, Fudan University, 220 Handan Road, Shanghai 200433, P. R. China
| | - Shaoheng Qin
- Molecular Catalysis, Department of Chemistry and Catalysis Research Center, School of Natural Sciences, Technical University Munich, Lichtenbergstr. 4, 85747 Garching bei München, Germany
| | - Yanzhi Zhang
- Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai 200032, P. R. China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, P. R. China
| | - Wangsheng Liu
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai 200438, P. R. China
| | - Jin Feng
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai 200438, P. R. China
| | - Hao Guo
- Academy for Engineering and Technology, Fudan University, 220 Handan Road, Shanghai 200433, P. R. China
- Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai 200438, P. R. China
| | - Fritz E Kühn
- Molecular Catalysis, Department of Chemistry and Catalysis Research Center, School of Natural Sciences, Technical University Munich, Lichtenbergstr. 4, 85747 Garching bei München, Germany
| | - Yin Liu
- Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai 200032, P. R. China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, P. R. China
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9
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Uchikura T, Takahashi K, Oishi T, Akiyama T. Visible-light-driven enantioselective intermolecular [2 + 2] photocyclization utilizing bathochromic excitation mediated by a chiral phosphoric acid. Org Biomol Chem 2023; 21:9138-9142. [PMID: 37975203 DOI: 10.1039/d3ob01425h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
We report herein an enantioselective intermolecular [2 + 2] photocyclization of alkenyl 2-pyrrolyl ketones using the bathochromic shift mediated by a chiral phosphoric acid. This synthetic method provides access to cyclobutanes with up to 98% ee. According to the UV-Vis spectra, the bathochromic effect was observed by mixing alkenyl 2-pyrrolyl ketones and a chiral phosphoric acid. A non-linear correlation was observed between the ee of the catalyst and the ee of the cycloadduct, suggesting that both substrates bind to the chiral phosphoric acid and form a dimer complex before photocycloaddition.
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Affiliation(s)
- Tatsuhiro Uchikura
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, Toshima-ku, Tokyo, Japan.
| | - Kazuki Takahashi
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, Toshima-ku, Tokyo, Japan.
| | - Tatsushi Oishi
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, Toshima-ku, Tokyo, Japan.
| | - Takahiko Akiyama
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, Toshima-ku, Tokyo, Japan.
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10
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Genzink MJ, Rossler MD, Recendiz H, Yoon TP. A General Strategy for the Synthesis of Truxinate Natural Products Enabled by Enantioselective [2+2] Photocycloadditions. J Am Chem Soc 2023; 145:19182-19188. [PMID: 37603410 PMCID: PMC10528511 DOI: 10.1021/jacs.3c07132] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
Pseudodimeric cyclobutanes constitute a large class of natural products that could, in principle, be efficiently synthesized via [2+2] photocycloadditions. However, the difficulty in developing chemo-, regio-, diastereo-, and enantioselective cycloadditions has limited their use in asymmetric syntheses. Herein, we show that chiral acid catalysts promote highly selective visible-light photocycloadditions, the products of which can be quickly transformed into truxinate natural products. This general approach has enabled the synthesis of both dimeric and pseudodimeric cyclobutane natural products with excellent enantioselectivity.
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Affiliation(s)
- Matthew J. Genzink
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, United States
| | - Matthew D. Rossler
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, United States
| | - Herman Recendiz
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, United States
| | - Tehshik P. Yoon
- Department of Chemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706, United States
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11
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Schwinger DP, Pickl T, Bach T. Photochemical Isomerization of Cyclohept-1-ene-1-carbaldehyde: Strain-Release Cycloadditions and Ene Reactions. J Org Chem 2023; 88:12844-12852. [PMID: 37578442 DOI: 10.1021/acs.joc.3c01311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Cyclohept-1-ene-1-carbaldehyde undergoes photoinduced E → Z isomerization at λ = 350 nm. The ring strain facilitates Diels-Alder cycloaddiions with 1,3-dienes, [3 + 2] cycloadditions with 1,3-dipoles, and ene reactions with olefins. Products are trans-fused at the cycloheptane core and were obtained in yields of up to 82%. Single crystal X-ray analyses corroborated the constitution and relative configuration of key products. With BF3 as a Lewis acid and 2,3-dimethylbuta-1,3-diene, cyclohept-1-ene-1-carbaldehyde reacted in the dark and rearranged stereoselectively to a tricyclic ketone (87%).
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Affiliation(s)
- Daniel P Schwinger
- Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Thomas Pickl
- Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Lichtenbergstrasse 4, 85748 Garching, Germany
| | - Thorsten Bach
- Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Lichtenbergstrasse 4, 85748 Garching, Germany
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12
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Rolka AB, Archipowa N, Kutta RJ, König B, Toste FD. Hybrid Catalysts for Enantioselective Photo-Phosphoric Acid Catalysis. J Org Chem 2023; 88:6509-6522. [PMID: 37126846 PMCID: PMC10198958 DOI: 10.1021/acs.joc.3c00191] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The syntheses of two novel, organic, and chiral photocatalysts are presented. By combining donor-acceptor cyanoarene-based photocatalysts with a chiral phosphoric acid, bifunctional catalysts have been designed. In preliminary proof-of-concept reactions, their use in both enantioselective energy transfer and photoredox catalysis is demonstrated.
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Affiliation(s)
- Alessa B Rolka
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Nataliya Archipowa
- Institute of Biophysics and Physical Biochemistry, Faculty of Biology and Preclinical Medicine, University of Regensburg, D-93040 Regensburg, Germany
| | - Roger J Kutta
- Institute of Theoretical and Physical Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - Burkhard König
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - F Dean Toste
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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13
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Medici F, Puglisi A, Rossi S, Raimondi L, Benaglia M. Stereoselective [2 + 2] photodimerization: a viable strategy for the synthesis of enantiopure cyclobutane derivatives. Org Biomol Chem 2023; 21:2899-2904. [PMID: 36939196 DOI: 10.1039/d3ob00232b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
The [2 + 2] photodimerization of cinnamic acid derivatives to afford enantiopure cyclobutanes has been investigated. The use of a chiral auxiliary represents a convenient and straightforward method to exert enantiocontrol on the reaction. By exploiting Evans oxazolidinones, the stereoselective light-driven cyclisation affords a functionalised cyclobutane ring with up to 99% enantiocontrol after removing the chiral auxiliary. In-flow experiments allowed us to improve further the efficiency of the methodology, leading to high conversion and excellent enantioselectivity.
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Affiliation(s)
- Fabrizio Medici
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi, 19, 20133 Milano, Italy.
| | - Alessandra Puglisi
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi, 19, 20133 Milano, Italy.
| | - Sergio Rossi
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi, 19, 20133 Milano, Italy.
| | - Laura Raimondi
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi, 19, 20133 Milano, Italy.
| | - Maurizio Benaglia
- Dipartimento di Chimica, Università degli Studi di Milano, Via Golgi, 19, 20133 Milano, Italy.
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14
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Huang J, Wang L, Tang XY. Oxidative cross-coupling of quinoxalinones with indoles enabled by acidochromism. Org Biomol Chem 2023; 21:2709-2714. [PMID: 36928912 DOI: 10.1039/d3ob00280b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
An oxidative cross-coupling of quinoxalinones with indole derivatives via B(C6F5)3·H2O induced acidochromism of quinoxalinone derivatives was developed under mild and external photocatalyst-free conditions. The reaction shows excellent substrate scope, accommodating a wide range of functional groups. The usefulness of this strategy was demonstrated by the synthesis of the natural products Azacephalandole A and Cephalandole A in high yields. Moreover, the products are fluorophores showing prevalent fluorescence properties with a wide emission range and good relative quantum yields.
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Affiliation(s)
- Jie Huang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Semiconductor Chemistry Center, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, People's Republic of China.
| | - Long Wang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Semiconductor Chemistry Center, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, People's Republic of China.
| | - Xiang-Ying Tang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Semiconductor Chemistry Center, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, People's Republic of China.
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15
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Chen Q, Zhu Y, Shi X, Huang R, Jiang C, Zhang K, Liu G. Light-driven redox deracemization of indolines and tetrahydroquinolines using a photocatalyst coupled with chiral phosphoric acid. Chem Sci 2023; 14:1715-1723. [PMID: 36819858 PMCID: PMC9930931 DOI: 10.1039/d2sc06340a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/09/2023] [Indexed: 01/11/2023] Open
Abstract
The integration of oxidation and enantioselective reduction enables a redox deracemization to directly access enantioenriched products from their corresponding racemates. However, the solution of the kinetically microscopic reversibility of substrates used in this oxidation/reduction unidirectional event is a great challenge. To address this issue, we have developed a light-driven strategy to enable an efficient redox deracemization of cyclamines. The method combines a photocatalyst and a chiral phosphoric acid in a toluene/aqueous cyclodextrin emulsion biphasic co-solvent system to drive the cascade out-of-equilibrium. Systemic optimizations achieve a feasible oxidation/reduction cascade sequence, and mechanistic investigations demonstrate a unidirectional process. This single-operation cascade route, which involves initial photocatalyzed oxidation of achiral cyclamines to cyclimines and subsequent chiral phosphoric acid-catalyzed enantioselective reduction of cyclimines to chiral cyclamines, is suitable for constructing optically pure indolines and tetrahydroquinolines.
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Affiliation(s)
- Qipeng Chen
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Yuanli Zhu
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Xujing Shi
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Renfu Huang
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Chuang Jiang
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Kun Zhang
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
| | - Guohua Liu
- International Joint Laboratory on Resource Chemistry of Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University Shanghai 200234 P. R. China
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16
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Kumar GS, Sha MS, Yempally S, Cabibihan JJ, Sadasivuni KK. A practical perspective for chromatic orthogonality for implementing in photolithography. Sci Rep 2023; 13:694. [PMID: 36639436 PMCID: PMC9839670 DOI: 10.1038/s41598-023-27869-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
Theoretically, it is more challenging to anticipate the conversion and selectivity of a photochemical experiment compared to thermally generated reactivity. This is due to the interaction of light with a photoreactive substrate. Photochemical reactions do not yet receive the same level of broad analytical study. Here, we close this research gap by presenting a methodology for statistically forecasting the time-dependent progression of photoreactions using widely available LEDs. This study uses NiS/ZnO in perovskite (MAPbI3) solar cells as an additive (5 volume %). The effect of monolithic perovskite solar cells (mPSCs) on forecasting the wavelength of LEDs has been carefully investigated using various characterization methods, including X-ray diffraction (XRD) and Transmission electron microscopy (TEM). The photocatalytic activity was analyzed by measuring the voltage produced. Various factors like selectivity, stability and sensitivity were also examined. This work provides a new perspective to validate NiS/ZnO photocatalysts for predicting the wavelength of different light sources and to apply in photolithography.
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Affiliation(s)
| | - Mizaj Shabil Sha
- grid.412603.20000 0004 0634 1084Center for Advanced Materials, Qatar University, PO Box 2713, Doha, Qatar
| | - Swathi Yempally
- grid.412603.20000 0004 0634 1084Center for Advanced Materials, Qatar University, PO Box 2713, Doha, Qatar
| | - John-John Cabibihan
- grid.412603.20000 0004 0634 1084Department of Mechanical and Industrial Engineering, Qatar University, PO Box 2713, Doha, Qatar
| | - Kishor Kumar Sadasivuni
- grid.412603.20000 0004 0634 1084Center for Advanced Materials, Qatar University, PO Box 2713, Doha, Qatar
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17
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Jones B, Solon P, Popescu MV, Du JY, Paton R, Smith MD. Catalytic Enantioselective 6π Photocyclization of Acrylanilides. J Am Chem Soc 2022; 145:171-178. [PMID: 36571763 PMCID: PMC9837842 DOI: 10.1021/jacs.2c09267] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Controlling absolute stereochemistry in catalytic photochemical reactions is generally challenging owing to high rates of background reactivity. Successful strategies broadly rely on selective excitation of the reaction substrate when associated with a chiral catalyst. Recent studies have demonstrated that chiral Lewis acid complexes can enable selective energy transfer from a photosensitizer to facilitate enantioselective triplet state reactions. Here, we apply this approach to the enantioselective catalysis of a 6π photocyclization through the design of an iridium photosensitizer optimized to undergo energy transfer to a reaction substrate only in the presence of a chiral Lewis acid complex. Among a group of iridium(III) sensitizers, enantioselectivity and yield closely correlate with photocatalyst triplet energy within a narrow window enabled by a modest reduction in substrate triplet energy upon binding a scandium/ligand complex. These results demonstrate that photocatalyst tuning offers a means to suppress background reactivity and improve enantioselectivity in photochemical reactions.
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Affiliation(s)
- Benjamin
A. Jones
- Chemistry
Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.
| | - Pearse Solon
- Chemistry
Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.
| | - Mihai V. Popescu
- Chemistry
Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.,Department
of Chemistry, Colorado State University, 1301 Center Avenue, Ft. Collins, Colorado 80523-1872, United States
| | - Ji-Yuan Du
- Chemistry
Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.
| | - Robert Paton
- Department
of Chemistry, Colorado State University, 1301 Center Avenue, Ft. Collins, Colorado 80523-1872, United States,
| | - Martin D. Smith
- Chemistry
Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.,
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18
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Verma R, Jindal P, Prasad J, Kothari SL, Lamba NP, Dandia A, Khangarot RK, Chauhan MS. Recent Trends in Photocatalytic Enantioselective Reactions. Top Curr Chem (Cham) 2022; 380:48. [DOI: 10.1007/s41061-022-00402-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/31/2022] [Indexed: 11/30/2022]
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19
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Stegbauer S, Jandl C, Bach T. Chiral Lewis acid catalysis in a visible light-triggered cycloaddition/rearrangement cascade. Chem Sci 2022; 13:11856-11862. [PMID: 36320923 PMCID: PMC9580482 DOI: 10.1039/d2sc03159k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 09/18/2022] [Indexed: 07/10/2024] Open
Abstract
Cascade (domino) reactions facilitate the formation of complex molecules from simple starting materials in a single operation. It was found that 1-naphthaldehyde derivatives can be converted to enantioenriched (82-96% ee) polycyclic benzoisochromenes via a cascade of ortho photocycloaddition and ensuing acid-catalysed rearrangement reactions. The cascade was initiated by irradiation with visible light (λ = 457 nm) and catalysed by a chiral AlBr3-activated 1,3,2-oxazaborolidine (14 examples, 65-93% yield). The absolute configuration of the products was elucidated by single crystal X-ray crystallography. Mechanistic experiments suggest that the ortho photocycloaddition occurs on the triplet hypersurface and that the chiral catalyst induces in this step the observed enantioselectivity.
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Affiliation(s)
- Simone Stegbauer
- Technische Universität München, School of Natural Sciences, Department of Chemistry and Catalysis Research Center Lichtenbergstrasse 4 Garching 85747 Germany https://www.ch.nat.tum.de/en/oc1/home/ +49 (0)89 289 13315
| | - Christian Jandl
- Technische Universität München, School of Natural Sciences, Department of Chemistry and Catalysis Research Center Lichtenbergstrasse 4 Garching 85747 Germany https://www.ch.nat.tum.de/en/oc1/home/ +49 (0)89 289 13315
| | - Thorsten Bach
- Technische Universität München, School of Natural Sciences, Department of Chemistry and Catalysis Research Center Lichtenbergstrasse 4 Garching 85747 Germany https://www.ch.nat.tum.de/en/oc1/home/ +49 (0)89 289 13315
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20
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Schirmer TE, König B. Ion-Pairing Catalysis in Stereoselective, Light-Induced Transformations. J Am Chem Soc 2022; 144:19207-19218. [PMID: 36240496 DOI: 10.1021/jacs.2c04759] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
With the rapid development of photoredox catalysis, numerous concepts for asymmetric induction were successfully and broadly adapted from polar two-electron transformations to radical chemistry. While this applies to organocatalysis or transition metal chemistry, asymmetric ion-pairing catalysis remains a niche application within light-driven reactions today. This perspective gives an overview of recent examples, strategies, and their application in stereoselective transformations at the interface of ion-pairing and photo(redox) catalysis.
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Affiliation(s)
- Tobias E Schirmer
- Institute of Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Burkhard König
- Institute of Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
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21
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Le TMT, Brégent T, Jubault P, Poisson T. Photocatalytic
E
→
Z Contra
‐Thermodynamic Isomerization of Vinyl Silanes with Lewis Base. Chemistry 2022; 28:e202201514. [PMID: 35652371 PMCID: PMC9541780 DOI: 10.1002/chem.202201514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Indexed: 11/22/2022]
Abstract
Herein, we disclosed the contra‐thermodynamic E→Z isomerization of alkenyl silanes, according to the in situ formation of a chromophoric species, in the presence of rac‐BINAP as the catalyst. The reaction carried out in DMSO or CH3CN under irradiation at 405 nm allowed the interconversion of the E‐isomers into the Z‐congeners in good to excellent yields and outstanding Z/E selectivities, on 18 examples. Finally, the mechanism of this E→Z isomerization was studied to get insight into the reaction mechanism.
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Affiliation(s)
- Thi Minh Thi Le
- Normandie Univ. INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) 76000 Rouen France
| | - Thibaud Brégent
- Normandie Univ. INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) 76000 Rouen France
| | - Philippe Jubault
- Normandie Univ. INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) 76000 Rouen France
| | - Thomas Poisson
- Normandie Univ. INSA Rouen UNIROUEN CNRS COBRA (UMR 6014) 76000 Rouen France
- Institut Universitaire de France 1 rue Descartes 75231 Paris France
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22
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Soika J, McLaughlin C, Neveselý T, Daniliuc CG, Molloy JJ, Gilmour R. Organophotocatalytic N–O Bond Cleavage of Weinreb Amides: Mechanism-Guided Evolution of a PET to ConPET Platform. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Julia Soika
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Calum McLaughlin
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Tomáš Neveselý
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - John. J. Molloy
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Ryan Gilmour
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
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23
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Jeremias N, Peschel MT, Jaschke C, de Vivie-Riedle R, Bach T. Photochemical Ring Contraction of 5,5-Dialkylcyclopent-2-enones and in situ Trapping by Primary Amines. J Org Chem 2022; 88:6294-6303. [PMID: 35786889 DOI: 10.1021/acs.joc.2c01156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
If substituted in the 5,5-position, cyclopent-2-enones undergo a smooth photochemical rearrangement to ketenes. A concomitant cyclopropane formation occurs due to a 1,3-shift of the C5 carbon atom from the carbonyl carbon atom (C1) to carbon atom C3. In this study, the cyclopropyl-substituted ketene intermediates were trapped in situ by primary amines providing an efficient entry into 2,2-disubstituted cyclopropaneacetic amides (24 examples, 49-95% yield). A remarkable feature of the reaction is the fact that the photochemical rearrangement can occur from either the first excited singlet (S1) or the respective triplet state (T1). In line with experimental results (triplet quenching, sensitization), XMS-CASPT2 calculations support the existence of efficient reaction pathways to the intermediate ketene both on the singlet and on the triplet hypersurface.
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Affiliation(s)
- Noah Jeremias
- School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Martin T Peschel
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Constantin Jaschke
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Regina de Vivie-Riedle
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Thorsten Bach
- School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
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24
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Shimizu N, Shigemitsu H, Kida T, Bach T, Mori T. Visible Light-Induced Regio- and Enantiodifferentiating [2 + 2] Photocycloaddition of 1,4-Naphthoquinones Mediated by Oppositely Coordinating 1,3,2-Oxazaborolidine Chiral Lewis Acid. J Org Chem 2022; 87:8071-8083. [PMID: 35652135 DOI: 10.1021/acs.joc.2c00730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A range of asymmetric photochemical transformations using visible light have recently become considerably attractive. Among the various approaches, chiral Lewis acid association to enones for [2 + 2] and ortho photocycloadditions and oxadi-π-methane rearrangements have shown to be very promising. Naturally, chiral Lewis acid coordination protects one of the prochiral faces of the C═C double bond, which enables an effective enantiodifferentiation in the following bond-forming process(es). Here, we studied regio- and enantiodifferentiating [2 + 2] photocycloaddition reactions of naphthoquinone derivatives mediated by chiral oxazaborolidines. A stereochemical control was quite challenging for the 2-ene-1,4-dione substrate, as a double coordination of Lewis acid essentially cancels out the face selectivity, and a mono-coordination to each carbonyl group leads to an opposite stereochemical outcome. Furthermore, a stepwise coordination in the ground state of Lewis acid in a 1:1 fashion was practically inaccessible. We found that the excited-state decomplexation is a key to accomplish high regio- and enantioselectivities in the photocycloaddition of an ene-dione.
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Affiliation(s)
- Nao Shimizu
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Hajime Shigemitsu
- Integrated Frontier Research for Medical Science Division Institute for OTRI, Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Toshiyuki Kida
- Integrated Frontier Research for Medical Science Division Institute for OTRI, Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, Garching 85747, Germany
| | - Tadashi Mori
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
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25
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Takagi R, Tanimoto T. Enantioselective [2 + 2] photocycloaddition of quinolone using a C1-symmetric chiral phosphoric acid as a visible-light photocatalyst. Org Biomol Chem 2022; 20:3940-3947. [PMID: 35506886 DOI: 10.1039/d2ob00607c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The enantioselective intra- and intermolecular [2 + 2] photocycloaddition of quinolone using a C1-symmetric chiral phosphoric acid as a visible-light photocatalyst is developed. The thioxanthone chromophore on phosphoric acid plays an important role in both phototransformation and enantioselectivity.
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Affiliation(s)
- Ryukichi Takagi
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
| | - Takaaki Tanimoto
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
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26
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Xi Y, Huang W, Wang C, Ding H, Xia T, Wu L, Fang K, Qu J, Chen Y. Catalytic Asymmetric Diarylation of Internal Acyclic Styrenes and Enamides. J Am Chem Soc 2022; 144:8389-8398. [PMID: 35482430 DOI: 10.1021/jacs.2c03411] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Enantioselective transformations of olefins are among the most important strategies for the asymmetric synthesis of organic compounds. Chemo-, diastereo-, and stereoselective control of reactions with internal acyclic alkenes for the construction of functionalized acyclic alkanes still remain a persistent challenge. Here, we report a palladium-catalyzed asymmetric regiodivergent Heck-type diarylation of internal acyclic alkenes. The 1,2-diarylation of two accessible acyclic alkenes, cinnamyl carbamates and enamides with diazonium salts and aromatic boronic acids, furnishes products containing vicinal stereogenic centers via the stereospecific formation of carbonyl coordination-assisted transient palladacycles. Moreover, the asymmetric migratory diarylation of enamides enables the formation of incontiguous stereocenters by an interrupted diastereoselective 1,3-chain-walking process. This protocol streamlines access to highly functionalized multisubstituted enantioenriched carbamates and amine derivatives which are embedded in the key biologically active motifs.
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Affiliation(s)
- Yang Xi
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Wenyi Huang
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Chenchen Wang
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Haojie Ding
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Tingting Xia
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Licheng Wu
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Ke Fang
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jingping Qu
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Yifeng Chen
- Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
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27
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Yu H, Zhan T, Zhou Y, Chen L, Liu X, Feng X. Visible-Light-Activated Asymmetric Addition of Hydrocarbons to Pyridine-Based Ketones. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00789] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Han Yu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Tangyu Zhan
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yuqiao Zhou
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Long Chen
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
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28
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29
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Genzink MJ, Kidd JB, Swords WB, Yoon TP. Chiral Photocatalyst Structures in Asymmetric Photochemical Synthesis. Chem Rev 2022; 122:1654-1716. [PMID: 34606251 PMCID: PMC8792375 DOI: 10.1021/acs.chemrev.1c00467] [Citation(s) in RCA: 126] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Asymmetric catalysis is a major theme of research in contemporary synthetic organic chemistry. The discovery of general strategies for highly enantioselective photochemical reactions, however, has been a relatively recent development, and the variety of photoreactions that can be conducted in a stereocontrolled manner is consequently somewhat limited. Asymmetric photocatalysis is complicated by the short lifetimes and high reactivities characteristic of photogenerated reactive intermediates; the design of catalyst architectures that can provide effective enantiodifferentiating environments for these intermediates while minimizing the participation of uncontrolled racemic background processes has proven to be a key challenge for progress in this field. This review provides a summary of the chiral catalyst structures that have been studied for solution-phase asymmetric photochemistry, including chiral organic sensitizers, inorganic chromophores, and soluble macromolecules. While some of these photocatalysts are derived from privileged catalyst structures that are effective for both ground-state and photochemical transformations, others are structural designs unique to photocatalysis and offer insight into the logic required for highly effective stereocontrolled photocatalysis.
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Affiliation(s)
- Matthew J Genzink
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jesse B Kidd
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Wesley B Swords
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Tehshik P Yoon
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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30
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Rigotti T, Schwinger DP, Graßl R, Jandl C, Bach T. Enantioselective crossed intramolecular [2+2] photocycloaddition reactions mediated by a chiral chelating Lewis acid. Chem Sci 2022; 13:2378-2384. [PMID: 35310494 PMCID: PMC8864722 DOI: 10.1039/d2sc00113f] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 02/01/2022] [Indexed: 12/01/2022] Open
Abstract
In intramolecular [2+2] photocycloaddition reactions, the two tethered olefins can approach each other in a straight or in a crossed fashion. Despite the fact that the latter reaction mode leads to intriguing, otherwise inaccessible bridged skeletons, there has so far not been any enantioselective variants thereof. This study concerned the crossed [2+2]-photocycloaddition of 2-(alkenyloxy)cyclohex-2-enones to bridged cyclobutanes. It was found that the reaction could be performed with high enantioselectivity (80–94% ee) under visible light conditions when employing a chiral rhodium Lewis acid as a catalyst (2 mol%). An enantioselective crossed [2+2] photocycloaddition is presented which proceeds under visible light irradiation in the presence of a chiral Lewis acidic metal complex. Chelation of two oxygen atoms to the metal centre accounts for the observed enantioface differentiation.![]()
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Affiliation(s)
- Thomas Rigotti
- School of Natural Sciences, Department Chemie, Catalysis Research Center (CRC), Technische Universität München 85747 Garching Germany +49 89 28913315 +49 89 28913330
| | - Daniel P Schwinger
- School of Natural Sciences, Department Chemie, Catalysis Research Center (CRC), Technische Universität München 85747 Garching Germany +49 89 28913315 +49 89 28913330
| | - Raphaela Graßl
- School of Natural Sciences, Department Chemie, Catalysis Research Center (CRC), Technische Universität München 85747 Garching Germany +49 89 28913315 +49 89 28913330
| | - Christian Jandl
- School of Natural Sciences, Department Chemie, Catalysis Research Center (CRC), Technische Universität München 85747 Garching Germany +49 89 28913315 +49 89 28913330
| | - Thorsten Bach
- School of Natural Sciences, Department Chemie, Catalysis Research Center (CRC), Technische Universität München 85747 Garching Germany +49 89 28913315 +49 89 28913330
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31
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Enantioselective intermolecular [2 + 2] photocycloadditions of vinylazaarenes with triplet-state electron-deficient olefins. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(22)64156-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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32
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Shibatani A, Kataoka Y, Ura Y. Palladium‐Catalyzed Aerobic α,β‐Dehydrogenation of Carboxylic Acids. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Ayaka Shibatani
- Department of Chemistry, Biology, and Environmental Science Faculty of Science Nara Women's University Kitauoyanishi-machi, Nara 630-8506 Japan
| | - Yasutaka Kataoka
- Department of Chemistry, Biology, and Environmental Science Faculty of Science Nara Women's University Kitauoyanishi-machi, Nara 630-8506 Japan
| | - Yasuyuki Ura
- Department of Chemistry, Biology, and Environmental Science Faculty of Science Nara Women's University Kitauoyanishi-machi, Nara 630-8506 Japan
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33
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Brégent T, Bouillon JP, Poisson T. Photocatalyzed E→Z Contra-thermodynamic Isomerization of Vinyl Boronates with Binaphthol. Chemistry 2021; 27:13966-13970. [PMID: 34411357 DOI: 10.1002/chem.202102536] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Indexed: 11/11/2022]
Abstract
The photocatalytic contra-thermodynamic E→Z isomerization of vinyl boronates by using a binaphthol catalyst is disclosed. The reaction, based on the transient formation of a suitable chromophore with a BINOL derivative as the catalyst, allowed geometrical isomerization in good-to-excellent Z/E ratio and excellent-to-quantitative yields. The mechanism of this E→Z contra-thermodynamic isomerization was studied, and the formation of a transient chromophore species is suggested.
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Affiliation(s)
- Thibaud Brégent
- Normandie Université, INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000, Rouen, France
| | - Jean-Philippe Bouillon
- Normandie Université, INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000, Rouen, France
| | - Thomas Poisson
- Normandie Université, INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000, Rouen, France.,Institut Universitaire de France, 1 rue Descartes, 75231, Paris, France
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34
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Sherbrook EM, Genzink MJ, Park B, Guzei IA, Baik MH, Yoon TP. Chiral Brønsted acid-controlled intermolecular asymmetric [2 + 2] photocycloadditions. Nat Commun 2021; 12:5735. [PMID: 34593790 PMCID: PMC8484615 DOI: 10.1038/s41467-021-25878-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 08/26/2021] [Indexed: 11/15/2022] Open
Abstract
Control over the stereochemistry of excited-state photoreactions remains a significant challenge in organic synthesis. Recently, it has become recognized that the photophysical properties of simple organic substrates can be altered upon coordination to Lewis acid catalysts, and that these changes can be exploited in the design of highly enantioselective catalytic photoreactions. Chromophore activation strategies, wherein simple organic substrates are activated towards photoexcitation upon binding to a Lewis acid catalyst, rank among the most successful asymmetric photoreactions. Herein, we show that chiral Brønsted acids can also catalyze asymmetric excited-state photoreactions by chromophore activation. This principle is demonstrated in the context of a highly enantio- and diastereoselective [2+2] photocycloaddition catalyzed by a chiral phosphoramide organocatalyst. Notably, the cyclobutane products arising from this method feature a trans-cis stereochemistry that is complementary to other enantioselective catalytic [2+2] photocycloadditions reported to date. Lewis acids have recently been shown to enable stereocontrol in photochemical cycloadditions, a difficult task due to the reactivity of excited-state compounds. Here the authors show that chiral Brønsted acids are competent chromophore activators in [2+2] cycloadditions, forming diastereomers disfavored in similar Lewis acid catalyzed photochemical reactions.
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Affiliation(s)
- Evan M Sherbrook
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin, 53706, USA
| | - Matthew J Genzink
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin, 53706, USA
| | - Bohyun Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Ilia A Guzei
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin, 53706, USA
| | - Mu-Hyun Baik
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea. .,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea.
| | - Tehshik P Yoon
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin, 53706, USA.
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35
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Jeremias N, Mohr LM, Bach T. Intermolecular [2 + 2] Photocycloaddition of α,β-Unsaturated Sulfones: Catalyst-Free Reaction and Catalytic Variants. Org Lett 2021; 23:5674-5678. [PMID: 34263603 DOI: 10.1021/acs.orglett.1c01794] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
2-Aryl-1-sulfonyl-substituted cyclobutanes were prepared in an intermolecular [2 + 2] photocycloaddition from various α,β-unsaturated sulfones and olefins upon irradiation at λ = 300 nm (26 examples, 60-99% yield). Lewis acids catalyzed the [2 + 2] photocycloaddition of 2-benzimidazolyl styryl sulfones. At short wavelengths, the latter substrates underwent C-S bond cleavage but AlBr3 (5 mol %) allowed for an intermolecular reaction with 2,3-dimethyl-2-butene at longer wavelengths. A chiral-at-metal Lewis acid (2 mol %) facilitated an enantioselective reaction (up to 77% ee).
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Affiliation(s)
- Noah Jeremias
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747 Garching, Germany
| | - Lisa-Marie Mohr
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747 Garching, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747 Garching, Germany
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36
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Großkopf J, Kratz T, Rigotti T, Bach T. Enantioselective Photochemical Reactions Enabled by Triplet Energy Transfer. Chem Rev 2021; 122:1626-1653. [PMID: 34227803 DOI: 10.1021/acs.chemrev.1c00272] [Citation(s) in RCA: 137] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
For molecules with a singlet ground state, the population of triplet states is mainly possible (a) by direct excitation and subsequent intersystem crossing or (b) by energy transfer from an appropriate sensitizer. The latter scenario enables a catalytic photochemical reaction in which the sensitizer adopts the role of a catalyst undergoing several cycles of photon absorption and subsequent energy transfer to the substrate. If the product molecule of a triplet-sensitized process is chiral, this process can proceed enantioselectively upon judicious choice of a chiral triplet sensitizer. An enantioselective reaction can also occur in a dual catalytic approach in which, apart from an achiral sensitizer, a second chiral catalyst activates the substrate toward sensitization. Although the idea of enantioselective photochemical reactions via triplet intermediates has been pursued for more than 50 years, notable selectivities exceeding 90% enantiomeric excess (ee) have only been realized in the past decade. This review attempts to provide a comprehensive survey on the various photochemical reactions which were rendered enantioselective by triplet sensitization.
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Affiliation(s)
- Johannes Großkopf
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thilo Kratz
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thomas Rigotti
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
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37
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Peschel MT, Kabaciński P, Schwinger DP, Thyrhaug E, Cerullo G, Bach T, Hauer J, Vivie‐Riedle R. Activation of 2‐Cyclohexenone by BF
3
Coordination: Mechanistic Insights from Theory and Experiment. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016653] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Martin T. Peschel
- Department Chemie Ludwig-Maximilians-Universität München 81377 München Germany
| | - Piotr Kabaciński
- IFN-CNR and Dipartimento di Fisica Politecnico di Milano 20133 Milano Italy
| | - Daniel P. Schwinger
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Erling Thyrhaug
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Giulio Cerullo
- IFN-CNR and Dipartimento di Fisica Politecnico di Milano 20133 Milano Italy
| | - Thorsten Bach
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Regina Vivie‐Riedle
- Department Chemie Ludwig-Maximilians-Universität München 81377 München Germany
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38
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Peschel MT, Kabaciński P, Schwinger DP, Thyrhaug E, Cerullo G, Bach T, Hauer J, de Vivie-Riedle R. Activation of 2-Cyclohexenone by BF 3 Coordination: Mechanistic Insights from Theory and Experiment. Angew Chem Int Ed Engl 2021; 60:10155-10163. [PMID: 33595902 PMCID: PMC8252487 DOI: 10.1002/anie.202016653] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/01/2021] [Indexed: 11/22/2022]
Abstract
Lewis acids have recently been recognized as catalysts enabling enantioselective photochemical transformations. Mechanistic studies on these systems are however rare, either due to their absorption at wavelengths shorter than 260 nm, or due to the limitations of theoretical dynamic studies for larger complexes. In this work, we overcome these challenges and employ sub-30-fs transient absorption in the UV, in combination with a highly accurate theoretical treatment on the XMS-CASPT2 level. We investigate 2-cyclohexenone and its complex to boron trifluoride and analyze the observed dynamics based on trajectory calculations including non-adiabatic coupling and intersystem crossing. This approach explains all ultrafast decay pathways observed in the complex. We show that the Lewis acid remains attached to the substrate in the triplet state, which in turn explains why chiral boron-based Lewis acids induce a high enantioselectivity in photocycloaddition reactions.
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Affiliation(s)
- Martin T Peschel
- Department Chemie, Ludwig-Maximilians-Universität München, 81377, München, Germany
| | - Piotr Kabaciński
- IFN-CNR and Dipartimento di Fisica, Politecnico di Milano, 20133, Milano, Italy
| | - Daniel P Schwinger
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Erling Thyrhaug
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Giulio Cerullo
- IFN-CNR and Dipartimento di Fisica, Politecnico di Milano, 20133, Milano, Italy
| | - Thorsten Bach
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
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39
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Ma L, Feng W, Shang H, Lin X, Xi Y. Tunable photochemical 6π heterocyclization reactions mediated by a boron Lewis acid. NEW J CHEM 2021. [DOI: 10.1039/d1nj03218f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The regulation effect of boron Lewis acid catalyst on the photoinduced 6π heterocyclization was investigated by using multi-configurational ab initio calculations.
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Affiliation(s)
- Lishuang Ma
- Department of Chemistry, College of Science, China University of Petroleum (East China), Qingdao, 266580, P. R. China
| | - Wenxu Feng
- Department of Chemistry, College of Science, China University of Petroleum (East China), Qingdao, 266580, P. R. China
| | - Hongyan Shang
- Department of Chemistry, College of Science, China University of Petroleum (East China), Qingdao, 266580, P. R. China
- State Key Laboratory of Heavy Oil Processing China University of Petroleum (East China), Qingdao, 266580, P. R. China
| | - Xufeng Lin
- Department of Chemistry, College of Science, China University of Petroleum (East China), Qingdao, 266580, P. R. China
| | - Yanyan Xi
- State Key Laboratory of Heavy Oil Processing China University of Petroleum (East China), Qingdao, 266580, P. R. China
- College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, P. R. China
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40
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Arai N, Ohkuma T. Photosensitized Intramolecular [2+2] Cycloaddition of 1 H-Pyrrolo[2,3- b]pyridines Enabled by the Assistance of Lewis Acids. J Org Chem 2020; 85:15717-15725. [PMID: 33190476 DOI: 10.1021/acs.joc.0c02231] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The [2+2] photocycloaddition of alkenyl-tethered 1H-pyrrolo[2,3-b]pyridine derivatives sensitized with 3',4'-dimethoxyacetophenone under irradiation by a high-pressure mercury lamp through Pyrex glass was dramatically accelerated by the addition of Lewis acids, preferably Mg(OTf)2, to give the products stereoselectively in high yields. The reaction without a Lewis acid gave only small amounts of the [2+2] cycloaddition products. Conformational fixation of the substrates by coordination with a Lewis acid was presumed to facilitate the cycloaddition.
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Affiliation(s)
- Noriyoshi Arai
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan
| | - Takeshi Ohkuma
- Division of Applied Chemistry and Frontier Chemistry Center, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan
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41
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Li X, Kutta RJ, Jandl C, Bauer A, Nuernberger P, Bach T. Photochemically Induced Ring Opening of Spirocyclopropyl Oxindoles: Evidence for a Triplet 1,3‐Diradical Intermediate and Deracemization by a Chiral Sensitizer. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008384] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xinyao Li
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Roger J. Kutta
- Institut für Physikalische und Theoretische Chemie Universität Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Christian Jandl
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Andreas Bauer
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie Universität Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
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42
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Chen H, Lu F, Cheng Y, Jia Y, Lu L, Xiao W. Asymmetric Deoxygenative Cyanation of Benzyl Alcohols Enabled by Synergistic Photoredox and Copper Catalysis
†. CHINESE J CHEM 2020. [DOI: 10.1002/cjoc.202000309] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Hong‐Wei Chen
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
| | - Fu‐Dong Lu
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
| | - Ying Cheng
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
| | - Yue Jia
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
| | - Liang‐Qiu Lu
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
| | - Wen‐Jing Xiao
- CCNU‐uOttawa Joint Research Centre, Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University 152 Luoyu Road Wuhan Hubei 430079 China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry 345 Lingling Road Shanghai 200032 China
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43
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Qiu D, Lian C, Mao J, Fagnoni M, Protti S. Dyedauxiliary Groups, an Emerging Approach in Organic Chemistry. The Case of Arylazo Sulfones. J Org Chem 2020; 85:12813-12822. [PMID: 32956584 PMCID: PMC8011925 DOI: 10.1021/acs.joc.0c01895] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The number of research papers that report photocatalyst-free protocols is currently increasing. Among the different approaches proposed, the conversion of a strong C-X bond of a stable substrate into a photolabile reactive moiety has been recently proposed. In this Synopsis, we introduce the so-dubbed dyedauxiliary group strategy by focusing on arylazo sulfones that are bench stable and visible-light responsive derivatives of anilines that have been exploited as precursors of a wide range of intermediates, including carbon-centered radicals as well as aryl cations.
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Affiliation(s)
- Di Qiu
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, P.R. China
| | - Chang Lian
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, P.R. China
| | - Jinshan Mao
- Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, P.R. China
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, Pavia 27100, Italy
| | - Stefano Protti
- PhotoGreen Lab, Department of Chemistry, University of Pavia, V. Le Taramelli 12, Pavia 27100, Italy
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44
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Brégent T, Bouillon JP, Poisson T. Copper-Photocatalyzed Contra-Thermodynamic Isomerization of Polarized Alkenes. Org Lett 2020; 22:7688-7693. [PMID: 32945682 DOI: 10.1021/acs.orglett.0c02894] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The contra-thermodynamic isomerization of α- and β-substituted cinnamate derivatives catalyzed by the Cu(OAc)2/rac-BINAP complex under blue light irradiation is reported. The use of an oxazolidinone template, which favored the complexation of the copper catalyst to the substrate, allowed the E → Z isomerization of the catalytically formed chromophore under simple and robust reaction conditions in good to excellent ratios. The mechanism of this process based on the transient formation of a chromophore was also studied.
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Affiliation(s)
- Thibaud Brégent
- Normandie Univ, INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | | | - Thomas Poisson
- Normandie Univ, INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France.,Institut Universitaire de France, 1 rue Descartes, 75231 Paris, France
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45
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Prentice C, Morrisson J, Smith AD, Zysman-Colman E. Recent developments in enantioselective photocatalysis. Beilstein J Org Chem 2020; 16:2363-2441. [PMID: 33082877 PMCID: PMC7537410 DOI: 10.3762/bjoc.16.197] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/09/2020] [Indexed: 01/02/2023] Open
Abstract
Enantioselective photocatalysis has rapidly grown into a powerful tool for synthetic chemists. This review describes the various strategies for creating enantioenriched products through merging enantioselective catalysis and photocatalysis, with a focus on the most recent developments and a particular interest in the proposed mechanisms for each. With the aim of understanding the scope of each strategy, to help guide and inspire further innovation in this field.
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Affiliation(s)
- Callum Prentice
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, United Kingdom
| | - James Morrisson
- Pharmaceutical Sciences, IMED Biotech Unit, AstraZeneca, Macclesfield SK102NA, United Kingdom
| | - Andrew D Smith
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, United Kingdom
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, United Kingdom
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46
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Li X, Kutta RJ, Jandl C, Bauer A, Nuernberger P, Bach T. Photochemically Induced Ring Opening of Spirocyclopropyl Oxindoles: Evidence for a Triplet 1,3-Diradical Intermediate and Deracemization by a Chiral Sensitizer. Angew Chem Int Ed Engl 2020; 59:21640-21647. [PMID: 32757341 PMCID: PMC7756555 DOI: 10.1002/anie.202008384] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 07/23/2020] [Indexed: 12/17/2022]
Abstract
The photochemical deracemization of spiro[cyclopropane‐1,3′‐indolin]‐2′‐ones (spirocyclopropyl oxindoles) was studied. The corresponding 2,2‐dichloro compound is configurationally labile upon direct irradiation at λ=350 nm and upon irradiation at λ=405 nm in the presence of achiral thioxanthen‐9‐one as the sensitizer. The triplet 1,3‐diradical intermediate generated in the latter reaction was detected by transient absorption spectroscopy and its lifetime determined (τ=22 μs). Using a chiral thioxanthone or xanthone, with a lactam hydrogen bonding site as a photosensitizer, allowed the deracemization of differently substituted chiral spirocyclopropyl oxindoles with yields of 65–98 % and in 50–85 % ee (17 examples). Three mechanistic contributions were identified to co‐act favorably for high enantioselectivity: the difference in binding constants to the chiral thioxanthone, the smaller molecular distance in the complex of the minor enantiomer, and the lifetime of the intermediate 1,3‐diradical.
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Affiliation(s)
- Xinyao Li
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Roger J Kutta
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Christian Jandl
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Andreas Bauer
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
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Kremsmair A, Skotnitzki J, Knochel P. Diastereo- and Enantioselective Cross-Couplings of Secondary Alkylcopper Reagents with 3-Halogeno-Unsaturated Carbonyl Derivatives. Chemistry 2020; 26:11971-11973. [PMID: 32557902 PMCID: PMC7540566 DOI: 10.1002/chem.202002297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/17/2020] [Indexed: 01/28/2023]
Abstract
Chiral secondary alkylcopper reagents were prepared from the corresponding alkyl iodides with retention of configuration by an I/Li-exchange using tBuLi (-100 °C, 1 min) followed by a transmetalation with CuBr⋅P(OEt)3 (-100 °C, 20 s). These stereodefined secondary alkylcoppers underwent stereoretentive cross-couplings with several 3-iodo or 3-bromo unsaturated carbonyl derivatives leading to the corresponding γ-methylated Michael acceptors in good yields and with high diastereoselectivities (dr up to 96:4). The method was extended to enantiomerically enriched alkylcoppers, providing optically enriched advanced natural product intermediates with up to 90 % ee.
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Affiliation(s)
- Alexander Kremsmair
- Department Chemie & BiochemieLudwig Maximilians-Universität MünchenButenandtstraße 5–13, Haus F81377MünchenGermany
| | - Juri Skotnitzki
- Department Chemie & BiochemieLudwig Maximilians-Universität MünchenButenandtstraße 5–13, Haus F81377MünchenGermany
| | - Paul Knochel
- Department Chemie & BiochemieLudwig Maximilians-Universität MünchenButenandtstraße 5–13, Haus F81377MünchenGermany
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48
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Schwinger DP, Bach T. Chiral 1,3,2-Oxazaborolidine Catalysts for Enantioselective Photochemical Reactions. Acc Chem Res 2020; 53:1933-1943. [PMID: 32880165 PMCID: PMC7497702 DOI: 10.1021/acs.accounts.0c00379] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Asymmetric synthesis has posed a significant challenge to organic chemists for over a century. Several strategies have been developed to synthesize enantiomerically enriched compounds, which are ubiquitous in the pharmaceutical and agrochemical industries. While many organometallic and organic catalysts have been found to mediate thermal enantioselective reactions, the field of photochemistry lacks similar depth. Recently, chiral 1,3,2-oxazaborolidines have made the transition from Lewis acids that were exclusively applied to thermal reactions to catalysts for enantioselective photochemical reactions. Due to their modular structure, various 1,3,2-oxazaborolidines are readily available and can be easily fitted to a given chemical transformation. Their use holds great promise for future developments in photochemistry. This Account gives an overview of the substrate classes that are known to undergo enantioselective photochemical transformations in the presence of chiral 1,3,2-oxazaborolidines and touches on the catalytic mode of action, on the proposed enantiodifferentiation mechanism, as well as on recent computational studies.Based on the discovery that the presence of Lewis acids enhances the efficiency of coumarin [2 + 2] photocycloadditions, chiral 1,3,2-oxazaborolidines were applied in 2010 for the first time to prepare enantiomerically enriched photoproducts. These Lewis acids were then successfully used in intramolecular [2 + 2] photocycloaddition reactions of 1-alkenoyl-5,6-dihydro-4-pyridones and 3-alkenyloxy-2-cycloalkenones. In the course of this work, it became evident that the chiral 1,3,2-oxazaborolidine must be tailored to the specific reaction; it was shown that both inter- and intramolecular [2 + 2] photocycloadditions of cyclic enones can be conducted enantioselectively, but the aryl rings of the chiral Lewis acids require different substitution patterns. In all [2 + 2] photocycloaddition reactions in which chiral 1,3,2-oxazaborolidines were used as catalysts, the catalyst loading could not be decreased below 50 mol % without sacrificing enantioselectivity due to competitive racemic background reactions. To overcome this constraint, substrates that reacted exclusively when bound to an oxazaborolidine were tested, notably phenanthrene-9-carboxaldehydes and cyclohexa-2,4-dienones. The former substrate class underwent an ortho photocycloaddition, the latter an oxadi-π-methane rearrangement. Several new 1,3,2-oxazaborolidines were designed, and the products were obtained in high enantioselectivity with only 10 mol % of catalyst. Recently, an iridium-based triplet sensitizer was employed to facilitate enantioselective [2 + 2] photocycloadditions of cinnamates with 25 mol % of chiral 1,3,2-oxazaborolidine. In this case, the relatively low catalyst loading was possible because the oxazaborolidine-substrate complex exhibits a lower triplet energy and an improved electronic coupling compared to the uncomplexed substrate, allowing for a selective energy transfer.By synthetic and theoretical studies, it has become evident that chiral 1,3,2-oxazaborolidines are multifaceted catalysts: they change absorption behavior, alter energetic states, and induce chirality. While a diverse set of substrates has been shown to undergo enantioselective photochemical transformations in the presence of chiral 1,3,2-oxazaborolidines either through direct excitation or through triplet sensitization, these catalysts took on different roles for different substrates. Based on the studies presented in this Account, it can be assumed that there are still more photochemical reactions and substrate classes that could profit from chiral 1,3,2-oxazaborolidines.
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Affiliation(s)
- Daniel P. Schwinger
- Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Thorsten Bach
- Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
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Sheng H, Liu Q, Su XD, Lu Y, Wang ZX, Chen XY. Visible-Light-Triggered Iodinations Facilitated by Weak Electrostatic Interaction of N-Heterocyclic Carbenes. Org Lett 2020; 22:7187-7192. [DOI: 10.1021/acs.orglett.0c02523] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- He Sheng
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Qiang Liu
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-Di Su
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Lu
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Xiang Wang
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Xiang-Yu Chen
- School of Chemical Sciences, University of the Chinese Academy of Sciences, Beijing 100049, China
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50
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Chen H, Liu L, Huang T, Chen J, Chen T. Direct Dehydrogenation for the Synthesis of α,β‐Unsaturated Carbonyl Compounds. Adv Synth Catal 2020. [DOI: 10.1002/adsc.202000454] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Hong Chen
- Haikou Hospital affiliated to Xiangya School of MedicineCentral South University Haikou 570100 People's Republic of China
| | - Long Liu
- Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island ResourcesHainan Provincial Key Lab of Fine ChemHainan University Haikou 570228 People's Republic of China
| | - Tianzeng Huang
- Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island ResourcesHainan Provincial Key Lab of Fine ChemHainan University Haikou 570228 People's Republic of China
| | - Jing Chen
- Haikou Hospital affiliated to Xiangya School of MedicineCentral South University Haikou 570100 People's Republic of China
| | - Tieqiao Chen
- Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island ResourcesHainan Provincial Key Lab of Fine ChemHainan University Haikou 570228 People's Republic of China
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