1
|
Zhang Y, Zhu T, Lin Y, Wei X, Xie X, Lin R, Zhang Z, Fang W, Zhang JJ, Zhang Y, Hu MY, Cai L, Chen Z. Organo-photoredox catalyzed gem-difluoroallylation of ketone-derived dihydroquinazolinones via C(sp 3)-C bond and C(sp 3)-F bond cleavage. Org Biomol Chem 2024; 22:5561-5568. [PMID: 38916128 DOI: 10.1039/d4ob00671b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
An organo-photoredox catalyzed gem-difluoroallylation of both acyclic and cyclic ketone derivatives with α-trifluoromethyl alkenes has been demonstrated, thus giving access to a diverse set of gem-difluoroalkenes in moderate to high yields. Pro-aromatic dihydroquinazolinones can be either pre-formed or in situ generated for ketone activation. This reaction is characterized by readily available starting materials, mild reaction conditions, and broad substrate scope. The feasibility of this reaction has been highlighted by the late-stage modification of several natural products and drug-like molecules as well as the in vitro antifungal activity.
Collapse
Affiliation(s)
- Yue Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Tianshuai Zhu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Yuqian Lin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Xian Wei
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Xinyu Xie
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Ruofan Lin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Zhijie Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Weiwei Fang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Jing-Jing Zhang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Yue Zhang
- Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen), Nanjing 210014, Jiangsu, China.
| | - Meng-Yang Hu
- DreamChem (Tianjin) Co., Ltd., No. 4, Haitai Development 2nd Road, Binhai High-tech Zone, Tianjin, 300380, China
| | - Lingchao Cai
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| | - Zhen Chen
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, Jiangsu Key Lab of Biomass-Based Green Fuels and Chemicals, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
| |
Collapse
|
2
|
Miao HJ, Zhang JH, Li W, Yang W, Xin H, Gao P, Duan XH, Guo LN. Aromatization-driven deconstructive functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis. Chem Sci 2024; 15:8993-8999. [PMID: 38873081 PMCID: PMC11168144 DOI: 10.1039/d4sc01111b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/07/2024] [Indexed: 06/15/2024] Open
Abstract
Aromatization-driven deconstruction and functionalization of spiro dihydroquinazolinones via dual photoredox/nickel catalysis is developed. The aromatization effect was introduced to synergistically drive unstrained cyclic C-C bond cleavage, with the aim of overcoming the ring-size limitation of nitrogen-centered radical induced deconstruction of carbocycles. Herein, we demonstrate the synergistic photoredox/nickel catalyzed deconstructive cross-coupling of spiro dihydroquinazolinones with organic halides. Remarkably, structurally diverse organic halides including aryl, alkenyl, alkynyl, and alkyl bromides were compatible for the coupling. In addition, this protocol is also characterized by its mild and redox-neutral conditions, excellent functional group compatibility, high atom economy, and easy scalability. A telescoped procedure involving condensation and ring-opening/coupling was found to be accessible. This work provides a complementary strategy to the existing radical-mediated C-C bond cleavage of unstrained carbocycles.
Collapse
Affiliation(s)
- Hong-Jie Miao
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Jin-Hua Zhang
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Wenke Li
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Wenpeng Yang
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Hong Xin
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Pin Gao
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Xin-Hua Duan
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| | - Li-Na Guo
- School of Chemistry, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Engineering Research Center of Energy Storage Materials and Devices, Ministry of Education, Xi'an Jiaotong University Xi'an 710049 China
| |
Collapse
|
3
|
Zhang B, Bai H, Zhan B, Wei K, Nie S, Zhang X. Deacylative arylation and alkynylation of unstrained ketones. SCIENCE ADVANCES 2024; 10:eado0225. [PMID: 38669332 PMCID: PMC11051662 DOI: 10.1126/sciadv.ado0225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
Ketones are ubiquitous in bioactive natural products, pharmaceuticals, chemical feedstocks, and synthetic intermediates. Hence, deacylative coupling reactions enable the versatile elaboration of a plethora of chemicals to access complex drug candidates and natural products. Here, we present deacylative arylation and alkynylation strategies for the synthesis of a wide range of alkyl-tethered arenes and alkynes from cyclic ketones and methyl ketones under dual nickel/photoredox catalysis. This reaction begins by generating a pre-aromatic intermediate (PAI) through the condensation of the ketone and N'-methylpicolino-hydrazonamide (MPHA), followed by the oxidative cleavage of the PAI α-C─C bond to form an alkyl radical, which is subsequently intercepted by a Ni complex, facilitating the formation of diverse C(sp3)-C(sp2)/C(sp) bonds with remarkable generality. This protocol features a one-pot reaction capability, high regioselectivity and ring-opening efficiency, mild reaction conditions, and a broad substrate scope with excellent functional group compatibility.
Collapse
Affiliation(s)
- Boyi Zhang
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Hui Bai
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Beibei Zhan
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Kaihang Wei
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Shenyou Nie
- Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention (Ministry of Education), Institute of Life Sciences and Department of Urology, the Second Affiliated Hospital, Chongqing Medical University, Chongqing, 400016, China
| | - Xiaheng Zhang
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| |
Collapse
|
4
|
Anwar K, Capaldo L, Wan T, Noël T, Gómez-Suárez A. Modular synthesis of congested β 2,2-amino acids via the merger of photocatalysis and oxidative functionalisations. Chem Commun (Camb) 2024; 60:1456-1459. [PMID: 38223935 DOI: 10.1039/d3cc06172h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
A two-step protocol for the modular synthesis of β2- and α-quaternary β2,2-amino acid derivatives is reported. The key steps are a photocatalytic hydroalkylation reaction, followed by an oxidative functionalisation to access N-protected β-amino acids, esters, and amides. This strategy can be effectively scaled up via continuous-flow technology.
Collapse
Affiliation(s)
- Khadijah Anwar
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany.
| | - Luca Capaldo
- Flow Chemistry Group, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Ting Wan
- Flow Chemistry Group, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Timothy Noël
- Flow Chemistry Group, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Adrián Gómez-Suárez
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany.
| |
Collapse
|
5
|
Tsai ZN, Li LY, Paculba AS, Miñoza S, Tsao YT, Lin PS, Liao HH. Pro-aromatic Dihydroquinazolinones - From Multigram Synthesis to Reagents for Gram-scale Metallaphotoredox Reactions. Chem Asian J 2023:e202301004. [PMID: 38102804 DOI: 10.1002/asia.202301004] [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: 11/13/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 12/17/2023]
Abstract
Dihydroquinazolinone (DHQZ) has recently been harnessed as a ketone-derived pro-aromatic reagent extensively employed in (metalla)photoredox reactions as versatile group transfer agents. In this work, we outline a column chromatography-free protocol for the multigram-scale synthesis of pro-aromatic DHQZs as well as its use in a gram-scale nickel/photoredox dual-catalyzed cross-coupling in single-batch, photoflow, and simultaneous multiple smaller batches. While the single-batch approach leveraged moderate yields, a simple plug-flow photoreactor also exhibited amenable productivity (up to 45 % yield) despite the use of a heterogeneous base. Meanwhile, performing the metallaphotoredox-catalyzed reaction in multiple smaller batches in an improvised photoreactor facilitated high yields of up to 59 % and good reproducibility, implying a convenient alternative in the absence of photoflow setups.
Collapse
Affiliation(s)
- Zong-Nan Tsai
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Li-Yun Li
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Aira Shayne Paculba
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Shinje Miñoza
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Yong-Ting Tsao
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Pei-Shan Lin
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| | - Hsuan-Hung Liao
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
- Department of Applied and Medicinal Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan (ROC
- Green Hydrogen Research Center, National Sun Yat-sen University, Kaohsiung, Taiwan (ROC
| |
Collapse
|
6
|
Zhang Z, Zhu Q, Pyle D, Zhou X, Dong G. Methyl Ketones as Alkyl Halide Surrogates: A Deacylative Halogenation Approach for Strategic Functional Group Conversions. J Am Chem Soc 2023; 145:21096-21103. [PMID: 37712624 PMCID: PMC11102776 DOI: 10.1021/jacs.3c08176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Alkyl halides are versatile precursors to access diverse functional groups (FGs). Due to their lability, the development of surrogates for alkyl halides is strategically important for complex molecule synthesis. Given the stability and ease of derivatization inherent in common alkyl ketones, here we report a deacylative halogenation approach to convert various methyl ketones to the corresponding alkyl chlorides, bromides, and iodides. The reaction is driven by forming an aromatic byproduct, i.e., 1,2,4-triazole, in which N'-methylpicolinohydrazonamide (MPHA) is employed to form a prearomatic intermediate and halogen atom-transfer (XAT) reagents are used to quench the alkyl radical intermediate. The reaction is efficient in yielding primary and secondary alkyl halides from a wide range of methyl ketones with broad FG tolerance. It also works for complex natural-product-derived and fluoro-containing substrates. In addition, one-pot conversions of methyl ketones to various other FGs and annulations with alkenes and alkynes through deacylative halogenation are realized. Moreover, an unusual iterative homologation of alkyl iodides is also demonstrated. Finally, mechanistic studies reveal an intriguing double XAT process for the deacylative iodination reaction, which could have implications beyond this work.
Collapse
Affiliation(s)
- Zining Zhang
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Qi Zhu
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Daniel Pyle
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Xukai Zhou
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| |
Collapse
|
7
|
Ratnam S, Unone S, Janssen-Müller D. 2,2'-Biquinoline-Based Recyclable Electroauxiliaries for the Generation of Alkyl Radicals via C-C Bond Cleavage. Chemistry 2023; 29:e202301685. [PMID: 37265104 DOI: 10.1002/chem.202301685] [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: 05/26/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/03/2023]
Abstract
Alkyl radical precursors are essential for a wide variety of photocatalytic and 3d-metal-catalyzed C-C bond forming reactions. Neutral organic heterocycles as electroauxiliaries such as 4-alkyl Hantzsch esters have become reliable tools for alkyl radical formation. Here we show that 2,2'-biquinoline-derived alkyl-substituted dihydroquinolines act as competent radical precursors with the ability to form primary, secondary and tertiary alkyl radicals. Hydroalkylation of benzalmalononitriles and N-Boc protected diazenes has been achieved through copper catalysis under mild conditions of 50 °C with good to very good yields of up to 85 %. Furthermore, the dihydroquinolines' reactivity towards a denitrative alkylation of nitroolefins such as β-nitrostyrene was discovered. Most importantly, the released biquinoline can be recycled, which greatly improves the overall atom-economy of these alkyl radical precursors in comparison to previous N-heterocyclic electroauxiliaries.
Collapse
Affiliation(s)
- Shahilan Ratnam
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr. 2, 37077, Göttingen, Germany
| | - Shreya Unone
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr. 2, 37077, Göttingen, Germany
| | - Daniel Janssen-Müller
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstr. 2, 37077, Göttingen, Germany
| |
Collapse
|
8
|
Yedase GS, Arif M, Kuniyil R, Yatham VR. Photocatalytic Hydro Tri/Difluoromethylation of Alkenes with Bench Stable Tri/Difluoromethylating Reagents. Org Lett 2023; 25:6200-6205. [PMID: 37578816 DOI: 10.1021/acs.orglett.3c02413] [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
Herein, we demonstrate the synthesis and characterization of bench stable tri/difluoromethylating reagents and their potential applications in redox neutral hydro tri/difluoromethylation of alkenes enabled by visible light. The new tri/difluoromethylating reagents are obtained on a gram-scale through simply cyclocondensation of commercially available anthranilamide with phenyltrifluoro or difluoromethyl ketone. Preliminary mechanistic studies indicated that a canonical photoredox catalytic cycle is being operative. DFT studies support this and further reveal that deprotonation occurs before radical cleavage. DFT studies also show that the better yield with HCF2 reagent is attributed to the favorable expulsion of the corresponding radical moiety.
Collapse
Affiliation(s)
- Girish Suresh Yedase
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
| | - Munaifa Arif
- Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad 678557, India
| | - Rositha Kuniyil
- Department of Chemistry, Indian Institute of Technology Palakkad, Palakkad 678557, India
| | - Veera Reddy Yatham
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
| |
Collapse
|
9
|
Xu L, Shi H. Ruthenium-Catalyzed Activation of Nonpolar C-C Bonds via π-Coordination-Enabled Aromatization. Angew Chem Int Ed Engl 2023; 62:e202307285. [PMID: 37379224 DOI: 10.1002/anie.202307285] [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: 05/24/2023] [Revised: 06/26/2023] [Accepted: 06/27/2023] [Indexed: 06/30/2023]
Abstract
Activation of C-C bonds allows editing of molecular skeletons, but methods for selective activation of nonpolar C-C bonds in the absence of a chelation effect or a driving force derived from opening of a strained ring are scarce. Herein, we report a method for ruthenium-catalyzed activation of nonpolar C-C bonds of pro-aromatic compounds by means of π-coordination-enabled aromatization. This method was effective for cleavage of C-C(alkyl) and C-C(aryl) bonds and for ring-opening of spirocyclic compounds, providing an array of benzene-ring-containing products. The isolation of a methyl ruthenium complex intermediate supports a mechanism involving ruthenium-mediated C-C bond cleavage.
Collapse
Affiliation(s)
- Lun Xu
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
| | - Hang Shi
- Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou, 310030, Zhejiang Province, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, 310024, Zhejiang Province, China
| |
Collapse
|
10
|
Bag S, Ojha S, Venugopalan S, Sahoo B. Photocatalytic Alkylation/Arylative Cyclization of N-Acrylamides of N-Heteroarenes and Arylamines with Dihydroquinazolinones from Unactivated Ketones. J Org Chem 2023; 88:12121-12130. [PMID: 37515554 DOI: 10.1021/acs.joc.3c01149] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2023]
Abstract
We describe a visible-light photoredox-catalyzed alkylation/arylative cyclization of N-acrylamides─from 2-arylindoles, 2-arylbenzimidazoles, or N-substituted anilines─with ketone-derived dihydroquinazolinones, accessing indolo- and benzimidazolo[2,1-a]isoquinolines or 2-oxindoles. The consecutive incorporation of alkyl- and aryl-carbogenic motifs across a C=C bond via formal cleavage of ketone α-C-C and arene C-H bonds leads to the formation of five- and six-membered rings, with an all-carbon quaternary stereocenter. This dicarbofunctionalization elaborates aromatization-driven radical C-C functionalization of unactivated aliphatic ketones to construct diverse cyclic structures with functionality tolerance.
Collapse
Affiliation(s)
- Sandip Bag
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram - 695551, Kerala, India
| | - Shubham Ojha
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram - 695551, Kerala, India
| | - Sreelakshmi Venugopalan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram - 695551, Kerala, India
| | - Basudev Sahoo
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram - 695551, Kerala, India
| |
Collapse
|
11
|
Uchikura T, Nakamura H, Sakai H, Akiyama T. 2-Silylated Dihydroquinazolinone as a Photocatalytic Energy Transfer Enabled Radical Hydrosilylation Reagent. Chemistry 2023; 29:e202301090. [PMID: 37269182 DOI: 10.1002/chem.202301090] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/04/2023]
Abstract
The hydrosilylation of alkenes is one of the most important methods for the synthesis of organosilicon compounds. In addition to the platinum-catalyzed hydrosilylation, silyl radical addition reactions are notable as economic reactions. An efficient and widely applicable silyl radical addition reaction was developed by using 2-silylated dihydroquinazolinone derivatives under photocatalytic conditions. Electron-deficient alkenes and styrene derivatives underwent hydrosilylation to give addition products in good to high yields. Mechanistic studies indicated that the photocatalyst functioned not as a photoredox catalyst but as an energy transfer catalyst. DFT calculations clarified that the triplet excited state of 2-silylated dihydroquinazolinone derivatives released a silyl radical through the homolytic cleavage of a carbon-silicon bond, and this was followed by the hydrogen atom transfer pathway, not the redox pathway.
Collapse
Affiliation(s)
- Tatsuhiro Uchikura
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, 171-8588, Toshima-ku, Tokyo, Japan
| | - Haruka Nakamura
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, 171-8588, Toshima-ku, Tokyo, Japan
| | - Hinata Sakai
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, 171-8588, Toshima-ku, Tokyo, Japan
| | - Takahiko Akiyama
- Department of Chemistry, Faculty of Science, Gakushuin University, 1-5-1, Mejiro, 171-8588, Toshima-ku, Tokyo, Japan
| |
Collapse
|
12
|
Anwar K, Troyano FJA, Abazid AH, El Yarroudi O, Funes-Ardoiz I, Gómez-Suárez A. Modular Synthesis of Polar Spirocyclic Scaffolds Enabled by Radical Chemistry. Org Lett 2023; 25:3216-3221. [PMID: 37130365 DOI: 10.1021/acs.orglett.3c00869] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Herein, we report a highly modular strategy to access spirocyclic scaffolds from abundant starting materials, i.e., cyclic ketones and α-amino or oxamic acids. The sequence proceeds through a straightforward Knoevenagel condensation, followed by a domino Giese-type reaction/base-mediated cyclization process, to deliver a broad scope of polar spirocyclic scaffolds in good to excellent yields. The products can be readily diversified, thus increasing the versatility of our method to gain rapid access to libraries of potential druglike molecules.
Collapse
Affiliation(s)
- Khadijah Anwar
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
| | | | - Ayham H Abazid
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
| | - Oumayma El Yarroudi
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
| | - Ignacio Funes-Ardoiz
- Centro de Investigación en Síntesis Química (CISQ), Universidad de La Rioja, 26004 Logroño, Spain
| | - Adrián Gómez-Suárez
- Organic Chemistry, Bergische Universität Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
| |
Collapse
|
13
|
Mondal PP, Das S, Venugopalan S, Krishnan M, Sahoo B. Visible-Light-Photocatalyzed Dicarbofunctionalization of Conjugated Alkenes with Ketone-Based Dihydroquinazolinones. Org Lett 2023; 25:1441-1446. [PMID: 36820645 DOI: 10.1021/acs.orglett.3c00175] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
A visible-light-photocatalyzed 1,2-arylalkylation of N-(arylsulfonyl)acrylamides with ketone-based dihydroquinazolinones is described. The formal C-C bond cleavage of aliphatic ketones is unified with tandem radical alkylation/1,4-aryl migration/desulfonylation to forge two different types of vicinal C-C bonds and construct an all-carbon quaternary α-stereocenter, thus enhancing the carbogenic complexity and tolerating diverse functionalities. Additional to telescopic synthesis and product diversification, this method features a radical dicarbofunctionalization of conjugated N-(arylsulfonyl)acrylamides with a nucleophilic alkyl radical precursor (dihydroquinazolinone) utilizing oxygen as a green oxidant at ambient temperature.
Collapse
Affiliation(s)
- Pinku Prasad Mondal
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551 Kerala, India
| | - Subham Das
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551 Kerala, India
| | - Sreelakshmi Venugopalan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551 Kerala, India
| | - Malavika Krishnan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551 Kerala, India
| | - Basudev Sahoo
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, 695551 Kerala, India
| |
Collapse
|
14
|
Lv XY, Abrams R, Martin R. Copper-Catalyzed C(sp 3 )-Amination of Ketone-Derived Dihydroquinazolinones by Aromatization-Driven C-C Bond Scission. Angew Chem Int Ed Engl 2023; 62:e202217386. [PMID: 36576703 DOI: 10.1002/anie.202217386] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/28/2022] [Accepted: 12/28/2022] [Indexed: 12/29/2022]
Abstract
Herein, we describe the development of a copper-catalyzed C(sp3 )-amination of proaromatic dihydroquinazolinones derived from ketones. The reaction is enabled by the intermediacy of open-shell species arising from homolytic C-C bond-cleavage driven by aromatization. The protocol is characterized by its operational simplicity and generality, including chemical diversification of advanced intermediates.
Collapse
Affiliation(s)
- Xin-Yang Lv
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, c/Marcel⋅lí Domingo, 1, 43007, Tarragona, Spain
| | - Roman Abrams
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain
| | - Ruben Martin
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys, 23, 08010, Barcelona, Spain
| |
Collapse
|
15
|
Hu Z, Li R, Yang X. Pyridine coordination enabled stepwise PT/ET N-H transfer and metal-independent C-C cleavage mechanism for Cu-mediated dehydroacylation of unstrained ketones. Dalton Trans 2022; 51:18409-18415. [PMID: 36416298 DOI: 10.1039/d2dt03434d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A density functional theory study of copper-mediated dehydroacylation of 4-phenyl-2-butanone to the corresponding olefin reveals a flexible N-H transfer process and a metal-independent C-C cleavage mechanism. When N'-methylpicolinohydrazonamide (MPHA) acts as the activating reagent, N-H cleavage can easily take place via stepwise proton transfer/electron transfer (PT/ET) and the rate-determining step is C-C homolysis with a total free energy barrier of 22.6 kcal mol-1, which is consistent with experimental observation of no kinetic isotope effects (KIE) at β-H. Besides, copper is found to have little influence on C-C cleavage, but is responsible for triggering single electron oxidation of the pre-aromatic intermediate (PAI). When replacing MPHA with picolinohydrazonamide (PHA), the second N-H transfer is 2.7 kcal mol-1 more favorable than C-C cleavage and dominates the pathway to aromatization, which explains there being no C-C cleavage product well. When N'-methylbenzohydrazonamide (MBHA) is adopted, the lack of pyridine coordination significantly reduces the stability of CuII and N-H transfer proceeds via a much more difficult proton coupled electron transfer (PCET) pathway, thus making N-H cleavage a rate-determining step with a total free energy barrier of up to 28.1 kcal mol-1.
Collapse
Affiliation(s)
- Zhiyun Hu
- School of Materials Science and Engineering, Taizhou University, Taizhou 318000, P. R. China.
| | - Rongrong Li
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xinzheng Yang
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
16
|
Cong F, Mega RS, Chen J, Day CS, Martin R. Trifluoromethylation of Carbonyl and Unactivated Olefin Derivatives by C(sp 3 )-C Bond Cleavage. Angew Chem Int Ed Engl 2022; 62:e202214633. [PMID: 36416716 DOI: 10.1002/anie.202214633] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 11/24/2022]
Abstract
Herein, we report a Cu-mediated trifluoromethylation of carbonyl-type compounds and unactivated olefins enabled by visible-light irradiation via σ C(sp3 )-C bond-functionalization. The reaction is distinguished by its modularity, mild conditions and wide scope-even in the context of late-stage functionalization-thus offering a complementary approach en route to valuable C(sp3 )-CF3 architectures from easily accessible precursors.
Collapse
Affiliation(s)
- Fei Cong
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, c/Marcel ⋅ lí Domingo, 1, 43007, Tarragona, Spain
| | - Riccardo S Mega
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain
| | - Jinhong Chen
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, c/Marcel ⋅ lí Domingo, 1, 43007, Tarragona, Spain
| | - Craig S Day
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, c/Marcel ⋅ lí Domingo, 1, 43007, Tarragona, Spain
| | - Ruben Martin
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluïs Companys 23, 08010, Barcelona, Spain
| |
Collapse
|
17
|
Luguera Ruiz A, La Mantia M, Merli D, Protti S, Fagnoni M. Alkyl Radical Generation via C–C Bond Cleavage in 2-Substituted Oxazolidines. ACS Catal 2022; 12:12469-12476. [PMID: 36249874 PMCID: PMC9552967 DOI: 10.1021/acscatal.2c03768] [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: 08/01/2022] [Revised: 09/21/2022] [Indexed: 11/30/2022]
Abstract
![]()
There is an urgent need to develop uncharged radical
precursors
to be activated under mild photocatalyzed conditions. 2-Substituted-1,3-oxazolidines
(Eox < 1.3 V vs SCE, smoothly prepared
from the corresponding aldehydes) have been herein employed for the
successful release of tertiary, α-oxy, and α-amido radicals
under photo-organo redox catalysis. The reaction relies on the unprecedented
C–C cleavage occurring from the radical cation of these heterocyclic
derivatives. Such a protocol is applied to the visible-light-driven
conjugate radical addition onto Michael acceptors and vinyl (hetero)arenes
under mild metal-free conditions.
Collapse
Affiliation(s)
- Adrián Luguera Ruiz
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Marta La Mantia
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Daniele Merli
- 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
| |
Collapse
|
18
|
Dihydroquinazolinones as adaptative C(sp 3) handles in arylations and alkylations via dual catalytic C-C bond-functionalization. Nat Commun 2022; 13:2394. [PMID: 35504911 PMCID: PMC9064991 DOI: 10.1038/s41467-022-29984-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 04/04/2022] [Indexed: 11/24/2022] Open
Abstract
C–C bond forming cross-couplings are convenient technologies for the construction of functional molecules. Consequently, there is continual interest in approaches that can render traditionally inert functionality as cross-coupling partners, included in this are ketones which are widely-available commodity chemicals and easy to install synthetic handles. Herein, we describe a dual catalytic strategy that utilizes dihydroquinazolinones derived from ketone congeners as adaptative one-electron handles for forging C(sp3) architectures via α C–C cleavage with aryl and alkyl bromides. Our approach is achieved by combining the flexibility and modularity of nickel catalysis with the propensity of photoredox events for generating open-shell reaction intermediates. This method is distinguished by its wide scope and broad application profile––including chemical diversification of advanced intermediates––, providing a catalytic technique complementary to existing C(sp3) cross-coupling reactions that operates within the C–C bond-functionalization arena. Although derived from feedstock chemicals and therefore in principle abundant, ketones are not widely used as cross-coupling partners in organic synthesis. Herein, the authors use ketone derivatives as one-electron handles for forging C(sp3) architectures via dual photo- and nickel catalysis.
Collapse
|
19
|
Mohammadi M, Ghorbani-Choghamarani A. Synthesis and characterization of novel hercynite@sulfuric acid and its catalytic applications in the synthesis of polyhydroquinolines and 2,3-dihydroquinazolin-4(1 H)-ones. RSC Adv 2022; 12:2770-2787. [PMID: 35425328 PMCID: PMC8979139 DOI: 10.1039/d1ra07381h] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 01/10/2022] [Indexed: 12/12/2022] Open
Abstract
Herein, we report the synthesis of hercynite@sulfuric acid as a novel nanomagnetic solid acid catalyst, containing the sulfuric acid catalytic sites on the surface of hercynite MNPs as the catalytic support. The as-synthesized nanocomposite was meticulously characterized using a wide range of physicochemical techniques; including, FT-IR, XRD, EDX, X-ray-mapping, SEM and VSM analysis. The catalytic activity of this nanomagnetic material was considered for the synthesis of the diversely substituted polyhydroquinolines and 2,3-dihydroquinazolin-4(1H)-ones under solvent free conditions and also cyclocondensation reactions in ethanol, respectively affording good to excellent yields. Moreover, it is worth mentioning that the heterogeneity of the catalyst was measured through its excellent reusability and hot-filtration test. Herein, we report the synthesis of hercynite@sulfuric acid as a novel nanomagnetic solid acid catalyst, containing the sulfuric acid catalytic sites on the surface of hercynite MNPs as the catalytic support.![]()
Collapse
Affiliation(s)
- Masoud Mohammadi
- Department of Chemistry, Faculty of Science, Ilam University P.O. Box 69315516 Ilam Iran
| | - Arash Ghorbani-Choghamarani
- Department of Organic Chemistry, Faculty of Chemistry, Bu-Ali Sina University Hamedan 6517838683 Iran +98 8138380709 +98 8138282807
| |
Collapse
|
20
|
Lee SC, Li LY, Tsai ZN, Lee YH, Tsao YT, Huang PG, Cheng CK, Lin HB, Chen TW, Yang CH, Chiu CC, Liao HH. Aromatization as an Impetus to Harness Ketones for Metallaphotoredox-Catalyzed Benzoylation/Benzylation of (Hetero)arenes. Org Lett 2021; 24:85-89. [PMID: 34913706 DOI: 10.1021/acs.orglett.1c03672] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Herein we report ketones as feedstock materials in radical cross-coupling reactions under Ni/photoredox dual catalysis. In this approach, simple condensation first converts ketones into prearomatic intermediates that then act as activated radical sources for cross-coupling with aryl halides. Our strategy enables the direct benzylation/benzoylation of (hetero)arenes under mild reaction conditions with high functional group tolerance.
Collapse
Affiliation(s)
- Shao-Chi Lee
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Li-Yun Li
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Zong-Nan Tsai
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Yi-Hsin Lee
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Yong-Ting Tsao
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Pin-Gong Huang
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Cheng-Ku Cheng
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Heng-Bo Lin
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Ting-Wei Chen
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Chung-Hsin Yang
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Cheng-Chau Chiu
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| | - Hsuan-Hung Liao
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan, R.O.C
| |
Collapse
|
21
|
Zhou X, Xu Y, Dong G. Olefination via Cu-Mediated Dehydroacylation of Unstrained Ketones. J Am Chem Soc 2021; 143:20042-20048. [PMID: 34807585 DOI: 10.1021/jacs.1c09587] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dehydroacylation of ketones to olefins is realized under mild conditions, which exhibits a unique reaction pathway involving aromatization-driven C-C cleavage to remove the acyl moiety, followed by Cu-mediated oxidative elimination to form an alkene between the α and β carbons. The newly adopted N'-methylpicolinohydrazonamide (MPHA) reagent is key to enable efficient cleavage of ketone C-C bonds at room temperature. Diverse alkyl- and aryl-substituted olefins, dienes, and special alkenes are generated with broad functional group tolerance. Strategic applications of this method are also demonstrated.
Collapse
Affiliation(s)
- Xukai Zhou
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Yan Xu
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| | - Guangbin Dong
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States
| |
Collapse
|
22
|
|
23
|
Li X, He S, Song Q. Rapid incorporation of a difluoroacetate radical into para-quinone methides via radical 1,6-conjugate addition. Chem Commun (Camb) 2021; 57:6035-6038. [PMID: 34037000 DOI: 10.1039/d1cc02149d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Presented herein is a newly designed strategy that rapidly introduces ethyl difluoroacetate radicals through a dialkylzincs induced radical 1,6-conjugate addition pathway. Besides achieving high yields and excellent functional group compatibility, this protocol allowed the incorporation of a gem-difluoromethylene motif to be accomplished within minutes.
Collapse
Affiliation(s)
- Xin Li
- Institute of Next Generation Matter Transformation, College of Materials Science & Engineering, Huaqiao University, 668 Jimei Blvd, Xiamen 361021, Fujian, China.
| | - Songtao He
- Institute of Next Generation Matter Transformation, College of Materials Science & Engineering, Huaqiao University, 668 Jimei Blvd, Xiamen 361021, Fujian, China.
| | - Qiuling Song
- Institute of Next Generation Matter Transformation, College of Materials Science & Engineering, Huaqiao University, 668 Jimei Blvd, Xiamen 361021, Fujian, China. and State Key Laboratory of Organometallic Chemistry and Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| |
Collapse
|