51
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Hoque MM, Bari MA, Khan MW. Rh(II)‐mediated one‐pot synthesis of dihydrobenzofuran and spiro[2.5]oct‐1‐ene: Experimental and DFT studies. J PHYS ORG CHEM 2021. [DOI: 10.1002/poc.4300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Mohammad Mazharol Hoque
- Department of Chemistry Bangladesh University of Engineering and Technology Dhaka Bangladesh
| | - Md. Abdul Bari
- Department of Chemistry Bangladesh University of Engineering and Technology Dhaka Bangladesh
| | - Md. Wahab Khan
- Department of Chemistry Bangladesh University of Engineering and Technology Dhaka Bangladesh
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52
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de Gracia Retamosa M, Ruiz‐Olalla A, Agirre M, de Cózar A, Bello T, Cossío FP. Additive and Emergent Catalytic Properties of Dimeric Unnatural Amino Acid Derivatives: Aldol and Conjugate Additions. Chemistry 2021; 27:15671-15687. [PMID: 34453455 PMCID: PMC9293019 DOI: 10.1002/chem.202102394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Indexed: 01/14/2023]
Abstract
Different densely substituted L- and D-proline esters were prepared by asymmetric (3+2) cycloaddition reactions catalyzed by conveniently selected EhuPhos chiral ligands. The γ-nitro-2-alkoxycarbonyl pyrrolidines thus obtained in either their endo or exo forms were functionalized and coupled to yield the corresponding γ-dipeptides. The catalytic properties of these latter dimers were examined using aldol and conjugate additions as case studies. When aldol reactions were analyzed, an additive behavior in terms of stereocontrol was observed on going from the monomers to the dimers. In contrast, in the case of the conjugate additions between ketones and nitroalkenes, the monomers did not catalyze this reaction, whereas the different γ-dipeptides promoted the formation of the corresponding Michael adducts. Therefore, in this latter case emergent catalytic properties were observed for these novel γ-dipeptides based on unnatural proline derivatives. Under certain conditions stoichiometric amounts of ketone, acid and nitroalkene), formation of N-acyloxy-2-oxooctahydro-1H-indoles was observed.
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Affiliation(s)
- María de Gracia Retamosa
- Donostia International Physics Center (DIPC)P° Manuel Lardizabal 420018Donostia/San SebastiánSpain
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
- Present address: Departamento de Química Orgánica and Centro de Innovación en Químca Avanzada (ORFEO-CINQA)Instituto de Síntesis OrgánicaUniversidad de Alicante03080AlicanteSpain
| | - Andrea Ruiz‐Olalla
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
| | - Maddalen Agirre
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
- Present address: CIC Energigune, Parque Tecnológico de Álava01510Vitoria/GasteizSpain.
| | - Abel de Cózar
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
- Ikerbasque, Basque Foundation for SciencePlaza Euskadi 548009BilbaoSpain
| | - Tamara Bello
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
| | - Fernando P. Cossío
- Donostia International Physics Center (DIPC)P° Manuel Lardizabal 420018Donostia/San SebastiánSpain
- Departamento de Química Orgánica I and Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA)University of the Basque Country (UPV/EHU)P° Manuel Lardizabal 320018Donostia/San SebastiánSpain
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53
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Oka Y, Tsuzuki S, Moriyama K. Chiral anthranilic pyrrolidine as custom-made amine catalyst for enantioselective Michael reaction of nitroalkenes with carbonyl compounds. Chem Commun (Camb) 2021; 57:11457-11460. [PMID: 34632990 DOI: 10.1039/d1cc04453b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A chiral anthranilic pyrrolidine catalyst as a custom-made amine-catalyst was developed for the enantio- and diastereo selective Michael reaction of nitroalkenes with carbonyl compounds. In particular, a peptide-like catalyst in which an α-amino acid is attached to the anthranilic acid skeleton induced the high stereoselectivity of the reaction with aldehydes. Studies of the reaction mechanism indicated that the catalyst exhibits a divergent stereocontrol in the reaction, namely, steric control by a 2-substituted group on the catalyst and hydrogen-bonding control by a carboxylic acid group on the catalyst.
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Affiliation(s)
- Yukari Oka
- Department of Chemistry, Graduate School of Science and Soft Molecular Activation Research Center, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
| | - Seiji Tsuzuki
- Department of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan
| | - Katsuhiko Moriyama
- Department of Chemistry, Graduate School of Science and Soft Molecular Activation Research Center, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
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54
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Kovalevsky RA, Kucherenko AS, Korlyukov AA, Zlotin SG. Asymmetric Conjugate Addition of 3‐Hydroxychromen‐4‐Ones to Electron‐Deficient Olefins Catalyzed by Recyclable C
2
‐Symmetric Squaramide. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202101019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Ruslan A. Kovalevsky
- N.D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky Prospect 119991 Moscow Russian Federation
- M.V. Lomonosov Moscow State University Department of Chemistry Leninskie gory 1–3 119234 Moscow Russian Federation
| | - Alexander S. Kucherenko
- N.D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky Prospect 119991 Moscow Russian Federation
| | - Alexander A. Korlyukov
- A.N. Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences 119991 Moscow Russian Federation
| | - Sergei G. Zlotin
- N.D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky Prospect 119991 Moscow Russian Federation
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55
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Towards Data‐Driven Design of Asymmetric Hydrogenation of Olefins: Database and Hierarchical Learning. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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56
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Regio‐controllable Cobalt‐Catalyzed Sequential Hydrosilylation/Hydroboration of Arylacetylenes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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57
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Kaneko M, Nakashima S. Density Functional Theory Study on the 193Ir Mössbauer Spectroscopic Parameters of Vaska's Complexes and Their Oxidative Adducts. Inorg Chem 2021; 60:12740-12752. [PMID: 34410705 DOI: 10.1021/acs.inorgchem.1c00239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the present study, density functional theory (DFT) calculation was applied to Vaska's complexes of formula trans-[IrIX(CO)(PPh3)2] and their oxidative adducts with small molecules (YZ) including H2, i.e., trans-[IrIIIClYZ(CO)(PPh3)2], to successfully correlate the electronic states of the complexes with the corresponding 193Ir Mössbauer spectroscopic parameters. After confirming the reproducibility of the DFT methods for elucidating the equilibrium structures and 193Ir Mössbauer isomer shifts of the octahedral Ir complexes, the isomer shifts and quadrupole splitting values of Vaska's complexes and their oxidative adducts were calculated. A bond critical point analysis revealed that the tendency in the isomer shifts was correlated with the strength of the covalent interaction in the coordination bonds. In an electric field gradient (EFG) analysis of the oxidative adducts, the sign of the principal axis was found to be positive for the complex with YZ = Cl2 and negative for the complex with YZ = H2. This reversal of the sign of the EFG principal axis was caused by the difference in the electron density distribution for the coordination bonds between Ir and YZ, according to a density of states analysis.
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Affiliation(s)
- Masashi Kaneko
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency, 2-4, Shirakata, Tokai-mura, Ibaraki 319-1195, Japan
| | - Satoru Nakashima
- Natural Science Center for Basic Research and Development, Hiroshima University, 1-4-2, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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58
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Origins of catalyst-controlled enantiodivergent hydroamination of enones with pyridazinones: A computational study. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.02.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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59
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Re-Examination of Proline-Catalyzed Intermolecular Aldol Reactions: An Ab Initio Kinetic Modelling Study. Top Catal 2021. [DOI: 10.1007/s11244-021-01501-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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60
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Kawada M, Tsuyusaki R, Nakashima K, Akutsu H, Hirashima SI, Matsumoto T, Yanai H, Miura T. Diaminomethylenemalononitrile as a Chiral Single Hydrogen Bond Catalyst: Application to Enantioselective Conjugate Addition of α-Branched Aldehydes. Chem Asian J 2021; 16:2272-2275. [PMID: 34216113 DOI: 10.1002/asia.202100487] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/22/2021] [Indexed: 11/09/2022]
Abstract
An improved diaminomethylenemalononitrile organocatalyst, bearing a N,N-disubstituted structure, promoted enantioselective conjugate addition reaction of α-branched aldehydes with vinyl sulfone, affording adducts with excellent enantioselectivities (up to 96% ee). Mechanistic studies revealed that the diaminomethylenemalononitrile motif holds the vinyl sulfone substrate using a single hydrogen bond accompanied by multiple weak interactions, including electrostatic C-H⋅⋅⋅O interactions.
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Affiliation(s)
- Masahiro Kawada
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Ryo Tsuyusaki
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Kosuke Nakashima
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Hiroshi Akutsu
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Shin-Ichi Hirashima
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Takashi Matsumoto
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Hikaru Yanai
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Tsuyoshi Miura
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
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61
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Xu LC, Zhang SQ, Li X, Tang MJ, Xie PP, Hong X. Towards Data-driven Design of Asymmetric Hydrogenation of Olefins: Database and Hierarchical Learning. Angew Chem Int Ed Engl 2021; 60:22804-22811. [PMID: 34370892 DOI: 10.1002/anie.202106880] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/14/2021] [Indexed: 11/09/2022]
Abstract
Asymmetric hydrogenation of olefins is one of the most powerful asymmetric transformations in molecular synthesis. Although several privileged catalyst scaffolds are available, the catalyst development for asymmetric hydrogenation is still a time- and resource-consuming process due to the lack of predictive catalyst design strategy. Targeting the data-driven design of asymmetric catalysis, we herein report the development of a standardized database that contains the detailed information of over 12000 literature asymmetric hydrogenations of olefins. This database provides a valuable platform for the machine learning applications in asymmetric catalysis. Based on this database, we developed a hierarchical learning approach to achieve predictive machine leaning model using only dozens of enantioselectivity data with the target olefin, which offers a useful solution for the few-shot learning problem and will facilitate the reaction optimization with new olefin substrate in catalysis screening.
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Affiliation(s)
- Li-Cheng Xu
- Zhejiang University, Department of Chemistry, CHINA
| | | | - Xin Li
- Zhejiang University, Department of Chemistry, CHINA
| | | | - Pei-Pei Xie
- Zhejiang University, Department of Chemistry, CHINA
| | - Xin Hong
- Zhejiang University, Department of Chemistry, 38 Zheda Road, 310028, Hangzhou, CHINA
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62
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Crawford JM, Kingston C, Toste FD, Sigman MS. Data Science Meets Physical Organic Chemistry. Acc Chem Res 2021; 54:10.1021/acs.accounts.1c00285. [PMID: 34351757 PMCID: PMC9078128 DOI: 10.1021/acs.accounts.1c00285] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
ConspectusAt the heart of synthetic chemistry is the holy grail of predictable catalyst design. In particular, researchers involved in reaction development in asymmetric catalysis have pursued a variety of strategies toward this goal. This is driven by both the pragmatic need to achieve high selectivities and the inability to readily identify why a certain catalyst is effective for a given reaction. While empiricism and intuition have dominated the field of asymmetric catalysis since its inception, enantioselectivity offers a mechanistically rich platform to interrogate catalyst-structure response patterns that explain the performance of a particular catalyst or substrate.In the early stages of an asymmetric reaction development campaign, the overarching mechanism of the reaction, catalyst speciation, the turnover limiting step, and many other details are unknown or posited based on related reactions. Considering the unclear details leading to a successful reaction, initial enantioselectivity data are often used to intuitively guide the ultimate direction of optimization. However, if the conditions of the Curtin-Hammett principle are satisfied, then measured enantioselectivity can be directly connected to the ensemble of diastereomeric transition states (TSs) that lead to the enantiomeric products, and the associated free energy difference between competing TSs (ΔΔG⧧ = -RT ln[(S)/(R)], where (S) and (R) represent the concentrations of the enantiomeric products). We, and others, speculated that this important piece of information can be leveraged to guide reaction optimization in a quantitative way.Although traditional linear free energy relationships (LFERs), such as Hammett plots, have been used to illuminate important mechanistic features, we sought to develop data science derived tools to expand the power of LFERs in order to describe complex reactions frequently encountered in modern asymmetric catalysis. Specifically, we investigated whether enantioselectivity data from a reaction can be quantitatively connected to the attributes of reaction components, such as catalyst and substrate structural features, to harness data for asymmetric catalyst design.In this context, we developed a workflow to relate computationally derived features of reaction components to enantioselectivity using data science tools. The mathematical representation of molecules can incorporate many aspects of a transformation, such as molecular features from substrate, product, catalyst, and proposed transition states. Statistical models relating these features to reaction outputs can be used for various tasks, such as performance prediction of untested molecules. Perhaps most importantly, statistical models can guide the generation of mechanistic hypotheses that are embedded within complex patterns of reaction responses. Overall, merging traditional physical organic experiments with statistical modeling techniques creates a feedback loop that enables both evaluation of multiple mechanistic hypotheses and future catalyst design. In this Account, we highlight the evolution and application of this approach in the context of a collaborative program based on chiral phosphoric acid catalysts (CPAs) in asymmetric catalysis.
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Affiliation(s)
- Jennifer M Crawford
- Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112, United States
| | - Cian Kingston
- Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112, United States
| | - F Dean Toste
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Matthew S Sigman
- Department of Chemistry, University of Utah, 315 S. 1400 E., Salt Lake City, Utah 84112, United States
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63
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Abstract
Computational methods have emerged as a powerful tool to augment traditional experimental molecular catalyst design by providing useful predictions of catalyst performance and decreasing the time needed for catalyst screening. In this perspective, we discuss three approaches for computational molecular catalyst design: (i) the reaction mechanism-based approach that calculates all relevant elementary steps, finds the rate and selectivity determining steps, and ultimately makes predictions on catalyst performance based on kinetic analysis, (ii) the descriptor-based approach where physical/chemical considerations are used to find molecular properties as predictors of catalyst performance, and (iii) the data-driven approach where statistical analysis as well as machine learning (ML) methods are used to obtain relationships between available data/features and catalyst performance. Following an introduction to these approaches, we cover their strengths and weaknesses and highlight some recent key applications. Furthermore, we present an outlook on how the currently applied approaches may evolve in the near future by addressing how recent developments in building automated computational workflows and implementing advanced ML models hold promise for reducing human workload, eliminating human bias, and speeding up computational catalyst design at the same time. Finally, we provide our viewpoint on how some of the challenges associated with the up-and-coming approaches driven by automation and ML may be resolved.
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Affiliation(s)
- Ademola Soyemi
- Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA.
| | - Tibor Szilvási
- Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA.
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64
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Cheng Z, Guo J, Sun Y, Zheng Y, Zhou Z, Lu Z. Regio-controllable Cobalt-Catalyzed Sequential Hydrosilylation/Hydroboration of Arylacetylenes. Angew Chem Int Ed Engl 2021; 60:22454-22460. [PMID: 34347353 DOI: 10.1002/anie.202109089] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 12/15/2022]
Abstract
Regiodivergent addition reactions provide straightforward and atom-economic approaches to access different regioisomers. However, the regio-chemistry control to access all the possible results is still challenging especially for the reaction involving multiple addition steps. Herein, we reported regio-controllable cobalt-catalyzed sequential hydrosilylation/hydroboration of arylacetylenes, delivering all the possible regio-outcomes with high regioselectivities (up to >20/1 rr for all the cases). Each regioisomer of value-added silylboronates could be efficiently and regioselectively obtained from the same materials. The adjustment of the ligands of cobalt catalysts combined with dual catalysis relay strategy is the key to achieve regio-chemistry control. This regio-controllable research might inspire the exploration of the diversity-oriented synthesis that involves multiple additions and provide full sets of regioisomers of other synthetic useful molecules.
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Affiliation(s)
- Zhaoyang Cheng
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Jun Guo
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Yufeng Sun
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Yushan Zheng
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Zhehong Zhou
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Zhan Lu
- Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
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65
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Wan Z, Wang QD, Liu D, Liang J. Accelerating the optimization of enzyme-catalyzed synthesis conditions via machine learning and reactivity descriptors. Org Biomol Chem 2021; 19:6267-6273. [PMID: 34195743 DOI: 10.1039/d1ob01066b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enzyme-catalyzed synthesis reactions are of crucial importance for a wide range of applications. An accurate and rapid selection of optimal synthesis conditions is crucial and challenging for both human knowledge and computer predictions. In this work, a new scenario, which combines a data-driven machine learning (ML) model with reactivity descriptors, is developed to predict the optimal enzyme-catalyzed synthesis conditions and the reaction yield. Fourteen reactivity descriptors in total are constructed to describe 125 reactions (classified into five categories) included in different reaction mechanisms. Nineteen ML models are developed to train the dataset and the Quadratic support vector machine (SVM) model is found to exhibit the best performance. The Quadratic SVM model is then used to predict the optimal reaction conditions, which are subsequently used to obtain the highest yield among 109 200 reaction conditions with different molar ratios of substrates, solvents, water contents, enzyme concentrations and temperatures for each reaction. The proposed protocol should be generally applicable to a diverse range of chemical reactions and provides a black-box evaluation for optimizing the reaction conditions of organic synthesis reactions.
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Affiliation(s)
- Zhongyu Wan
- Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, Low Carbon Energy Institute and School of Chemical Engineering, China University of Mining and Technology, Xuzhou, 221008, People's Republic of China. and School of Science, City University of Hong Kong, Hong Kong SAR 999077, People's Republic of China
| | - Quan-De Wang
- Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, Low Carbon Energy Institute and School of Chemical Engineering, China University of Mining and Technology, Xuzhou, 221008, People's Republic of China.
| | - Dongchang Liu
- School of Science, Xi'an Polytechnic University, Xi'an 710048, People's Republic of China and Department of Physics, Sungkyunkwan University, Suwon 16419, Korea
| | - Jinhu Liang
- School of Environment and Safety Engineering, North University of China, Taiyuan 030051, People's Republic of China
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66
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Abstract
Density functional theory (DFT) has been employed in predicting the enantioselectivity of the aldol reaction between acetone and p-nitrobenzaldehyde catalyzed by proline and its derivatives Me2bdc-Pro (bdc = 1,4-benzenedicarboxylate) and Me2bpdc-Pro (bpdc = 4,4'-biphenyldicarboxylate). For each catalyst, our computationally predicted values at the M062X/6-31+G(d) level of theory with the SMD solvent model are in excellent agreement with experimental results reported in the literature. Electron-donating and electron-withdrawing groups (viz., SO3-, NMe2, SO3H, and NMe3+) were installed at the C4 position of the proline-based catalysts to study the impact of electrostatic effects on stereoselectivity. The electron-donating groups decrease and even invert the enantioselectivity, while the electron-withdrawing ones increase it. Enantiomeric excesses in the range of 49-71 and 59-68% are predicted for Me2bdc-Pro and Me2bpdc-Pro catalysts with the electron-withdrawing SO3H and NMe3+ installed respectively, values much higher than those of the corresponding unmodified catalysts. More interestingly, enantiomeric excesses decrease and, in the case of SO3-, are even inverted in favor of the other enantiomer when the electron-donating groups are installed. These results highlight the importance of electrostatic effects, and polar effects more generally, in optimal organocatalyst design for stereoselective C-C bond-forming reactions.
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Affiliation(s)
- Li-Juan Yu
- ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michelle L Coote
- ARC Centre of Excellence for Electromaterials Science, Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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67
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Sulfide‐Catalyzed Diastereoselective Spirocyclopropanation: Constructing Spiro‐cyclopropanyl‐pyrazolones From α‐Arylidenepyrazolones. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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68
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Abstract
Machine learning (ML) techniques applied to chemical reactions have a long history. The present contribution discusses applications ranging from small molecule reaction dynamics to computational platforms for reaction planning. ML-based techniques can be particularly relevant for problems involving both computation and experiments. For one, Bayesian inference is a powerful approach to develop models consistent with knowledge from experiments. Second, ML-based methods can also be used to handle problems that are formally intractable using conventional approaches, such as exhaustive characterization of state-to-state information in reactive collisions. Finally, the explicit simulation of reactive networks as they occur in combustion has become possible using machine-learned neural network potentials. This review provides an overview of the questions that can and have been addressed using machine learning techniques, and an outlook discusses challenges in this diverse and stimulating field. It is concluded that ML applied to chemistry problems as practiced and conceived today has the potential to transform the way with which the field approaches problems involving chemical reactions, in both research and academic teaching.
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Affiliation(s)
- Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland.,Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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69
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Zhu L, Yang H, Wong MW. Asymmetric Nucleophilic Allylation of α-Chloro Glycinate via Squaramide Anion-Abstraction Catalysis: SN1 or SN2 Mechanism, or Both? J Org Chem 2021; 86:8414-8424. [DOI: 10.1021/acs.joc.1c00839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Lihan Zhu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
- Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Hui Yang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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70
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Gerasimov IS, Zahariev F, Leang SS, Tesliuk A, Gordon MS, Medvedev MG. Introducing LibXC into GAMESS (US). MENDELEEV COMMUNICATIONS 2021. [DOI: 10.1016/j.mencom.2021.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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71
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Introducing LibXC into GAMESS (US). MENDELEEV COMMUNICATIONS 2021. [DOI: 10.1016/j.mencom.2021.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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72
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Zahrt AF, Rinehart NI, Denmark SE. A Conformer‐Dependent, Quantitative Quadrant Model. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Andrew F. Zahrt
- Roger Adams Laboratory Department of Chemistry University of Illinois 600 S. Mathews Ave Urbana, IL 61801 USA
| | - N. Ian Rinehart
- Roger Adams Laboratory Department of Chemistry University of Illinois 600 S. Mathews Ave Urbana, IL 61801 USA
| | - Scott E. Denmark
- Roger Adams Laboratory Department of Chemistry University of Illinois 600 S. Mathews Ave Urbana, IL 61801 USA
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73
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Gallarati S, Fabregat R, Laplaza R, Bhattacharjee S, Wodrich MD, Corminboeuf C. Reaction-based machine learning representations for predicting the enantioselectivity of organocatalysts. Chem Sci 2021; 12:6879-6889. [PMID: 34123316 PMCID: PMC8153079 DOI: 10.1039/d1sc00482d] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/01/2021] [Indexed: 12/12/2022] Open
Abstract
Hundreds of catalytic methods are developed each year to meet the demand for high-purity chiral compounds. The computational design of enantioselective organocatalysts remains a significant challenge, as catalysts are typically discovered through experimental screening. Recent advances in combining quantum chemical computations and machine learning (ML) hold great potential to propel the next leap forward in asymmetric catalysis. Within the context of quantum chemical machine learning (QML, or atomistic ML), the ML representations used to encode the three-dimensional structure of molecules and evaluate their similarity cannot easily capture the subtle energy differences that govern enantioselectivity. Here, we present a general strategy for improving molecular representations within an atomistic machine learning model to predict the DFT-computed enantiomeric excess of asymmetric propargylation organocatalysts solely from the structure of catalytic cycle intermediates. Mean absolute errors as low as 0.25 kcal mol-1 were achieved in predictions of the activation energy with respect to DFT computations. By virtue of its design, this strategy is generalisable to other ML models, to experimental data and to any catalytic asymmetric reaction, enabling the rapid screening of structurally diverse organocatalysts from available structural information.
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Affiliation(s)
- Simone Gallarati
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Raimon Fabregat
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Rubén Laplaza
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Sinjini Bhattacharjee
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- Indian Institute of Science Education and Research Dr Homi Bhabha Rd, Ward No. 8, NCL Colony, Pashan Pune Maharashtra 411008 India
| | - Matthew D Wodrich
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Clemence Corminboeuf
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Competence in Research-Catalysis (NCCR-Catalysis), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Center for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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74
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Zhang P, Zhang Y, Li Z, Gao Y, Lei M, Yang Z, Pu M. Theoretical investigation of Prolyl‐Histidine‐catalyzed intermolecular aldol reaction. J PHYS ORG CHEM 2021. [DOI: 10.1002/poc.4203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Peihuan Zhang
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Yufeng Zhang
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Zhewei Li
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Yang Gao
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Ming Lei
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Zuoyin Yang
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
| | - Min Pu
- State Key Laboratory of Chemical Resource Engineering, Institute of Computational Chemistry Beijing University of Chemical Technology Beijing China
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75
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Zhang M, Wang Y, Li SJ, Wang X, Shi Q, Li X, Qu LB, Wei D, Lan Y. Multiple Functional Organocatalyst-Promoted Inert C–C Activation: Mechanism and Origin of Selectivities. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05511] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Min Zhang
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yang Wang
- Department of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China
| | - Shi-Jun Li
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Xinghua Wang
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Qianqian Shi
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Xue Li
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Ling-Bo Qu
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Donghui Wei
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
| | - Yu Lan
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, Henan 450001, China
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76
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Mao ZY, Ye JL, Nie XD, Si CM, Wei BG, Lin GQ. Synthesis of Functionalized Bicyclo[2.2.2]octan-2-ones Skeleton via Tandem Process of Amino Acid Involved Formal [4 + 2] and Decarboxylative-Mannich Sequence. J Org Chem 2021; 86:3276-3286. [PMID: 33530688 DOI: 10.1021/acs.joc.0c02620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An efficient approach to a functionalized bicyclo[2.2.2]octan-2-one scaffold has been developed through a one-pot cascade process including amino acid involved successive Michael addition and decarboxylative-Mannich sequence. Starting from α,β-unsaturated ketones and amino acids, a series of desired products 7a-7m and 8a-8o were obtained with moderate yields. In addition, the tandem process was reasonably explained by the results of DFT calculations.
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Affiliation(s)
- Zhuo-Ya Mao
- School of Pharmacy and Institutes of Biomedical Sciences, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Jian-Liang Ye
- College of Chemistry and Chemical Engineering and the Key Laboratory for Chemical Biology of Fujian Province, Xiamen University, Xiamen 361005, China
| | - Xiao-Di Nie
- School of Pharmacy and Institutes of Biomedical Sciences, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Chang-Mei Si
- School of Pharmacy and Institutes of Biomedical Sciences, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Bang-Guo Wei
- School of Pharmacy and Institutes of Biomedical Sciences, Fudan University, 826 Zhangheng Road, Shanghai 201203, China
| | - Guo-Qiang Lin
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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77
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Kirschtowski S, Jameel F, Stein M, Seidel-Morgenstern A, Hamel C. Kinetics of the reductive amination of 1-undecanal in thermomorphic multicomponent system. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2020.116187] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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78
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Nakliang P, Yoon S, Choi S. Emerging computational approaches for the study of regio- and stereoselectivity in organic synthesis. Org Chem Front 2021. [DOI: 10.1039/d1qo00531f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Computational chemistry has become important in organic synthesis as it provides a detailed understanding of molecular structures and properties and detailed reaction mechanisms.
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Affiliation(s)
- Pratanphorn Nakliang
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Sanghee Yoon
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
| | - Sun Choi
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Republic of Korea
- State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Xili, Nanshan District, Shenzhen, 518055, China
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79
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Genaev AM, Salnikov GE, Koltunov KY. Unusual temperature-sensitive protonation behaviour of 4-(dimethylamino)pyridine. Org Biomol Chem 2021; 19:866-872. [DOI: 10.1039/d0ob01893g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
An unusually strong impact of temperature on the protonation degree of DMAP in strong acid solutions has been found.
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Affiliation(s)
| | | | - Konstantin Yu. Koltunov
- Boreskov Institute of Catalysis
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk 630090
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80
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Diab S, Raiyat M, Gerogiorgis DI. Flow synthesis kinetics for lomustine, an anti-cancer active pharmaceutical ingredient. REACT CHEM ENG 2021. [DOI: 10.1039/d1re00184a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
An original reaction mechanism and kinetic parameter estimation has been achieved for lomustine, an anti-cancer active pharmaceutical ingredient (API).
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Affiliation(s)
- Samir Diab
- Institute for Materials and Processes (IMP), School of Engineering, University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FB, Scotland, UK
| | - Mateen Raiyat
- Institute for Materials and Processes (IMP), School of Engineering, University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FB, Scotland, UK
| | - Dimitrios I. Gerogiorgis
- Institute for Materials and Processes (IMP), School of Engineering, University of Edinburgh, The King's Buildings, Edinburgh, EH9 3FB, Scotland, UK
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81
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Liu C, Li SJ, Han P, Qu LB, Lan Y. How to inverse the chemoselectivity of nucleophilic addition by using a Lewis acid/Brønsted base pair catalyst: A theoretical view. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2020.111318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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82
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Urabe D, Fukaya K. Systematic Search for Transition States in Complex Molecules: Computational Analyses of Regio- and Stereoselective Interflavan Bond Formation in Flavan-3-ols. HETEROCYCLES 2021. [DOI: 10.3987/rev-20-943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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83
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Zahrt AF, Rose BT, Darrow WT, Henle JJ, Denmark SE. Computational methods for training set selection and error assessment applied to catalyst design: guidelines for deciding which reactions to run first and which to run next. REACT CHEM ENG 2021. [DOI: 10.1039/d1re00013f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Different subset selection methods are examined to guide catalyst selection in optimization campaigns. Error assessment methods are used to quantitatively inform selection of new catalyst candidates from in silico libraries of catalyst structures.
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Affiliation(s)
- Andrew F. Zahrt
- 245 Roger Adams Laboratory
- Department of Chemistry
- University of Illinois
- Urbana
- USA
| | - Brennan T. Rose
- 245 Roger Adams Laboratory
- Department of Chemistry
- University of Illinois
- Urbana
- USA
| | - William T. Darrow
- 245 Roger Adams Laboratory
- Department of Chemistry
- University of Illinois
- Urbana
- USA
| | - Jeremy J. Henle
- 245 Roger Adams Laboratory
- Department of Chemistry
- University of Illinois
- Urbana
- USA
| | - Scott E. Denmark
- 245 Roger Adams Laboratory
- Department of Chemistry
- University of Illinois
- Urbana
- USA
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84
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Lai J, Fianchini M, Pericàs MA. Development of Immobilized SPINOL-Derived Chiral Phosphoric Acids for Catalytic Continuous Flow Processes. Use in the Catalytic Desymmetrization of 3,3-Disubstituted Oxetanes. ACS Catal 2020. [DOI: 10.1021/acscatal.0c04497] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Junshan Lai
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans, 16, 43007 Tarragona, Spain
| | - Mauro Fianchini
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans, 16, 43007 Tarragona, Spain
| | - Miquel A. Pericàs
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), Av. Països Catalans, 16, 43007 Tarragona, Spain
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85
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Kee CW, Wong MW. Bicyclic Guanidine-Catalyzed Asymmetric Cycloaddition Reaction of Anthrones-Bifunctional Binding Modes and Origin of Stereoselectivity. J Org Chem 2020; 85:15139-15153. [PMID: 33175532 DOI: 10.1021/acs.joc.0c02008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We report a computational analysis of the [5,5] bicyclic guanidine-catalyzed asymmetric cycloaddition reaction of anthrones. Based on extensive conformational search of key intermediates and transition states on the potential energy surface and density functional theory calculations, we studied five plausible binding modes between the guanidine catalyst and substrates for this reaction. Our results indicate that the most favorable pathway is a stepwise conjugate addition-Aldol sequence via the dual hydrogen-bond binding mode. The predicted level of enantioselectivity is in good agreement with experimental values. Trends in variation of substrates and catalysts have also been reproduced by our calculations. Decomposition analysis revealed the significance of aromatic interactions in stabilizing the key enantioselectivity-determining transition state structures.
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Affiliation(s)
- Choon Wee Kee
- Process & Catalysis Research, Institute of Chemical and Engineering Sciences, 1 Pesek Road, Singapore 627899.,Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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86
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Zheng H, Xue XS. Recent Computational Studies on Mechanisms of Hypervalent Iodine(III)-Promoted Dearomatization of Phenols. CURR ORG CHEM 2020. [DOI: 10.2174/1385272824999200620223218] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypervalent iodine-promoted dearomatization of phenols has received intense
attention. This mini-review summarizes recent computational mechanistic studies of phenolic
dearomatizations promoted by hypervalent iodine(III) reagents or catalysts. The first part
of this review describes mechanisms of racemic dearomatization of phenols, paying special
attention to the associative and dissociative pathways. The second part focuses on mechanisms
and selectivities of diastereo- or enantio-selective dearomatization of phenols.
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Affiliation(s)
- Hanliang Zheng
- College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiao-Song Xue
- College of Chemistry, Nankai University, Tianjin 300071, China
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87
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Yadav J, Pawar AP, Nagare YK, Iype E, Rangan K, Ohshita J, Kumar D, Kumar I. Direct Amine-Catalyzed Enantioselective Synthesis of Pentacyclic Dibenzo[ b, f][1,4]oxazepine/Thiazepine-Fused Isoquinuclidines along with DFT Calculations. J Org Chem 2020; 85:14094-14108. [PMID: 33030896 DOI: 10.1021/acs.joc.0c02141] [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
A direct protocol for the asymmetric synthesis of dibenzoxazepine/thiazepine-fused [2.2.2] isoquinuclidines is developed. The reaction proceeds through a proline-catalyzed direct Mannich reaction followed by an intramolecular aza-Michael cascade sequence between 2-cyclohexene-1-one and various tricyclic imines, like dibenzoxazepines/thiazepines, as an overall [4 + 2] aza-Diels-Alder reaction. A series of pentacyclic isoquinuclidines have been prepared, with complete endo-selectivity, in good to high yields and excellent enantioselectivity (>99:1). Density functional theory (DFT) calculations further support the observed high stereochemical outcome of the reaction.
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Affiliation(s)
- Jyothi Yadav
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani 333031, Rajasthan, India
| | - Amol Prakash Pawar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani 333031, Rajasthan, India
| | - Yadav Kacharu Nagare
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani 333031, Rajasthan, India
| | - Eldhose Iype
- Department of Chemical Engineering, Birla Institute of Technology and Science, Pilani, Dubai Campus, Dubai 345055, UAE
| | - Krishnan Rangan
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Hyderabad Campus, Hyderabad 500078, Telangana, India
| | - Joji Ohshita
- Applied Chemistry Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Dalip Kumar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani 333031, Rajasthan, India
| | - Indresh Kumar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani 333031, Rajasthan, India
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88
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Vijayapritha S, Murugan K, Viswanathamurthi P, Vijayan P, Kalaiarasi C. Synthesis and structural characterization of facile ruthenium(II) hydrazone complexes: Efficient catalysts in α-alkylation of ketones with primary alcohols via hydrogen auto transfer. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119887] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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89
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Murugan K, Vijayapritha S, Kavitha V, Viswanathamurthi P. Versatile formation of Ru(II) hydrazone complexes: Structure, theoretical studies and catalytic activity in α-alkylation. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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90
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Jain S, Vanka K. The Effect of Solvent-Substrate Noncovalent Interactions on the Diastereoselectivity in the Intramolecular Carbonyl-Ene and the Staudinger [2 + 2] Cycloaddition Reactions. J Phys Chem A 2020; 124:8019-8028. [PMID: 32894951 DOI: 10.1021/acs.jpca.0c05738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Noncovalent interactions (NCIs) have been identified as important contributing factors for determining selectivity in organic transformations. However, cases where NCIs between solvents and substrates are responsible for a major extent for determining selectivity are rare. The current computational study with density functional theory identifies two important transformations where this is the case: the intramolecular carbonyl-ene reaction and the Staudinger [2 + 2] cycloaddition reaction. In both cases, the role of explicit solvent molecules interacting noncovalently with the substrate has been taken into account. Calculations indicate that the diastereomeric ratio would be 95.0:5.0 for the formation of tricyclic tetrahydrofuran diastereomers via the intramolecular carbonyl-ene reaction and 94.0:6.0 for the formation of the triflone diastereomers via the Staudinger [2 + 2] cycloaddition reaction, which corroborates with the experiment. Interestingly, in both the cases, the calculations indicate that noninclusion of explicit solvent molecules would lead to only a small difference between the competing transition states, which leads to the conclusion that solvent-substrate NCIs are the major cause for diastereoselectivity in both the cases considered.
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Affiliation(s)
- Shailja Jain
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Kumar Vanka
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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91
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Melancon KM, Cundari TR. Computational investigations of NHC-backbone configurations for applications in organocatalytic umpolung reactions. Org Biomol Chem 2020; 18:7437-7447. [PMID: 32940280 DOI: 10.1039/d0ob01267j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Density functional theory (DFT) and multiconfigurational self-consistent field theory (MCSCF) methods are employed to investigate variation of the electronic properties of various N-heterocyclic carbenes. Alterations to the backbone by increased or decreased conjugation, heteroatom substitution in the NHC ring, and electron-donating or -withdrawing backbone substituents are modeled. The MCSCF calculations show extensive delocalization of both the highest occupied and lowest unoccupied molecular orbitals for NHCs with polymerizable backbone substituents. The free energies of the intermediates and transition structures for benzoin condensation are also shown to be sensitive to substitution of the NHC backbone. Taken together, these results imply great sensitivity of the reactivity of poly(NHC) catalysts to backbone modification at this moiety. Implications with respect to enhancement of poly(NHC)s employed in umpolung catalysis are discussed.
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Affiliation(s)
- Kortney M Melancon
- University of North Texas, Department of Chemistry, Denton, Texas 76201, USA.
| | - Thomas R Cundari
- University of North Texas, Department of Chemistry, Denton, Texas 76201, USA.
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92
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Hoque MM, Hussen MS, Kumer A, Khan MW. Synthesis of 5, 6-diaroylisoindoline-1, 3-dione and computational approaches for investigation on structural and mechanistic insights by DFT. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1811866] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Mohammad Mazharol Hoque
- Department of Chemistry, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Md. Sajib Hussen
- Department of Chemistry, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Ajoy Kumer
- Department of Chemistry, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Md. Wahab Khan
- Department of Chemistry, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
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93
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Blank BR, Andrews IP, Kwon O. Phosphine-Catalyzed (4+1) Annulation: Rearrangement of Allenylic Carbamates to 3-Pyrrolines through Phosphonium Diene Intermediates. ChemCatChem 2020; 12:4352-4372. [PMID: 34447481 PMCID: PMC8386297 DOI: 10.1002/cctc.202000626] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Indexed: 01/02/2023]
Abstract
We have developed a phosphine-catalyzed (4+1) annulative rearrangement for the preparation of 3-pyrrolines from allenylic carbamates via phosphonium diene intermediates. We employed this methodology to synthesize an array of 1,3-disubstituted- and 1,2,3-trisubstituted-3-pyrrolines, including the often difficult to prepare 2-alkyl variants. A mechanistic investigation employing allenylic acetates and mononucleophiles unexpectedly unveiled that a phosphine-catalyzed (4+1) reaction for the construction of cyclopentene products, previously reported by Tong, might not occur through a phosphonium diene, as had been proposed, but rather through multiple mechanisms working in concert. Consequently, our phosphine-catalyzed rearrangement is most likely the first transformation to involve the unequivocal formation of a phosphonium diene intermediate along the reaction pathway. To demonstrate the synthetic utility of this newly developed reaction, we have completed concise formal syntheses of the pyrrolizidine alkaloids (±)-trachelanthamidine and (±)-supinidine.
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Affiliation(s)
- Brian R Blank
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California, 90095-1569 (USA)
| | - Ian P Andrews
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California, 90095-1569 (USA)
| | - Ohyun Kwon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California, 90095-1569 (USA)
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94
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Merten C. Recent Advances in the Application of Vibrational Circular Dichroism Spectroscopy for the Characterization of Asymmetric Catalysts. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000876] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Christian Merten
- Fakultät für Chemie und Biochemie Organische Chemie II Ruhr Universität Bochum Universitätsstraße 150 44801 Bochum Germany
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95
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Hartmann PE, Lazzarotto M, Pletz J, Tanda S, Neu P, Goessler W, Kroutil W, Boese AD, Fuchs M. Mechanistic Studies of the TRIP-Catalyzed Allylation with Organozinc Reagents. J Org Chem 2020; 85:9672-9679. [PMID: 32648755 PMCID: PMC7418105 DOI: 10.1021/acs.joc.0c00992] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
3,3-Bis(2,4,6-triisopropylphenyl)-1,1-binaphthyl-2,2-diyl
hydrogenphosphate
(TRIP) catalyzes the asymmetric allylation of aldehydes with organozinc
compounds, leading to highly valuable structural motifs, like precursors
to lignan natural products. Our previously reported mechanistic proposal
relies on two reaction intermediates and requires further investigation
to really understand the mode of action and the origins of stereoselectivity.
Detailed ab initio calculations, supported by experimental data, render
a substantially different mode of action to the allyl boronate congener.
Instead of a Brønsted acid-based catalytic activation, the chiral
phosphate acts as a counterion for the Lewis acidic zinc ion, which
provides the activation of the aldehyde.
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Affiliation(s)
- Peter E Hartmann
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe.,Physical and Theoretical Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/IV, 8010 Graz, Austria, Europe
| | - Mattia Lazzarotto
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Jakob Pletz
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Stefan Tanda
- Analytical Chemistry, Institute of Chemistry, University of Graz, Universitätsplatz 1/I, 8010 Graz, Austria, Europe
| | - Philipp Neu
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - Walter Goessler
- Analytical Chemistry, Institute of Chemistry, University of Graz, Universitätsplatz 1/I, 8010 Graz, Austria, Europe
| | - Wolfgang Kroutil
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
| | - A Daniel Boese
- Physical and Theoretical Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/IV, 8010 Graz, Austria, Europe
| | - Michael Fuchs
- Bioorganic and Organic Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/II, 8010 Graz, Austria, Europe
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96
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Gerosa GG, Marcarino MO, Spanevello RA, Suárez AG, Sarotti AM. Re-Engineering Organocatalysts for Asymmetric Friedel–Crafts Alkylation of Indoles through Computational Studies. J Org Chem 2020; 85:9969-9978. [DOI: 10.1021/acs.joc.0c01256] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Gabriela G. Gerosa
- Instituto de Quı́mica Rosario (CONICET-UNR), Facultad de Ciencias Bioquı́micas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Maribel O. Marcarino
- Instituto de Quı́mica Rosario (CONICET-UNR), Facultad de Ciencias Bioquı́micas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Rolando A. Spanevello
- Instituto de Quı́mica Rosario (CONICET-UNR), Facultad de Ciencias Bioquı́micas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Alejandra G. Suárez
- Instituto de Quı́mica Rosario (CONICET-UNR), Facultad de Ciencias Bioquı́micas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Ariel M. Sarotti
- Instituto de Quı́mica Rosario (CONICET-UNR), Facultad de Ciencias Bioquı́micas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
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97
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Li X, Xu J, Li SJ, Qu LB, Li Z, Chi YR, Wei D, Lan Y. Prediction of NHC-catalyzed chemoselective functionalizations of carbonyl compounds: a general mechanistic map. Chem Sci 2020; 11:7214-7225. [PMID: 34123007 PMCID: PMC8159411 DOI: 10.1039/d0sc01793k] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Generally, N-heterocyclic carbene (NHC) complexed with carbonyl compounds would transform into several important active intermediates, i.e., enolates, Breslow intermediates, or acylazolium intermediates, which act as either a nucleophile (Nu) or an electrophile (E) to react with the other E/Nu partner. Hence, the key to predicting the origin of chemoselectivity is to compute the activity (i.e., electrophilic index ω for E and nucleophilic index N for Nu) and stability of the intermediates and products, which are suggested in a general mechanistic map of these reactions. To support this point, we selected and studied different cases of the NHC-catalyzed reactions of carbonyl compounds in the presence of a base and/or an oxidant, in which multiple possible pathways involving acylazolium, enolate, Breslow, and α,β-unsaturated acylazolium intermediates were proposed and a novel index ω + N of the E and Nu partners was employed to exactly predict the energy barrier of the chemoselective step in theory. This work provides a guide for determining the general principle behind organocatalytic reactions with various chemoselectivities, and suggests a general application of the reaction index in predicting the chemoselectivity of the nucleophilic and electrophilic reactions. A novel index ω + N can be used to predict the chemoselectivity according to the general NHC-catalyzed reaction mechanism.![]()
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Affiliation(s)
- Xue Li
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China
| | - Jun Xu
- College of Pharmacy, Guizhou University of Traditional Chinese Medicine Guiyang China
| | - Shi-Jun Li
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China
| | - Ling-Bo Qu
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China
| | - Zhongjun Li
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China
| | - Yonggui Robin Chi
- Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
| | - Donghui Wei
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China
| | - Yu Lan
- College of Chemistry, Institute of Green Catalysis, Zhengzhou University 100 Science Avenue Zhengzhou Henan 450001 China .,College of Chemistry and Chemical Engineering, Chongqing University Chongqing 400044 China
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98
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Henle JJ, Zahrt AF, Rose BT, Darrow WT, Wang Y, Denmark SE. Development of a Computer-Guided Workflow for Catalyst Optimization. Descriptor Validation, Subset Selection, and Training Set Analysis. J Am Chem Soc 2020; 142:11578-11592. [PMID: 32568531 DOI: 10.1021/jacs.0c04715] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Modern, enantioselective catalyst development is driven largely by empiricism. Although this approach has fostered the introduction of most of the existing synthetic methods, it is inherently limited by the skill, creativity, and chemical intuition of the practitioner. Herein, we present a complementary approach to catalyst optimization in which statistical methods are used at each stage to streamline development. To construct the optimization informatics workflow, a number of critical components had to be subjected to rigorous validation. First, the critically important molecular descriptors were validated in two case studies to establish the importance of conformation-dependent molecular representations. Next, with a large data set available, it was possible to investigate the amount of data necessary to make predictive models with different modeling methods. Given the commercial availability of many catalyst structures, it was possible to compare models generated with algorithmically selected training sets and commercially available training sets. Finally, the augmentation of limited data sets is demonstrated in a method informed by unsupervised learning to restore the accuracy of the generated models.
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Affiliation(s)
- Jeremy J Henle
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Andrew F Zahrt
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Brennan T Rose
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - William T Darrow
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Yang Wang
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Scott E Denmark
- Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
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99
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Xiao Y, Zhao J, Zhao M, Chong R, Li X, Qiao Y. Mechanism, Chemoselectivity, and Stereoselectivity of NHC‐Catalyzed Asymmetric Desymmetrization of Enal‐Tethered Cyclohexadienones. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yang Xiao
- Department of Pathophysiology School of Basic Medical Sciences Zhengzhou University 450001 Zhengzhou Henan China
- Collaborative Innovation Center of Henan Province for Cancer Chemoprevention Zhengzhou University 450001 Zhengzhou Henan China
| | - Jimin Zhao
- Department of Pathophysiology School of Basic Medical Sciences Zhengzhou University 450001 Zhengzhou Henan China
- Collaborative Innovation Center of Henan Province for Cancer Chemoprevention Zhengzhou University 450001 Zhengzhou Henan China
| | - Miao Zhao
- Department of Pathophysiology School of Basic Medical Sciences Zhengzhou University 450001 Zhengzhou Henan China
- Collaborative Innovation Center of Henan Province for Cancer Chemoprevention Zhengzhou University 450001 Zhengzhou Henan China
| | - Ruifeng Chong
- Institute of Environmental and Analytical Sciences College of Chemistry and Chemical Engineering Henan University 475001 Kaifeng China
| | - Xin Li
- Department of Pathophysiology School of Basic Medical Sciences Zhengzhou University 450001 Zhengzhou Henan China
- Collaborative Innovation Center of Henan Province for Cancer Chemoprevention Zhengzhou University 450001 Zhengzhou Henan China
| | - Yan Qiao
- Department of Pathophysiology School of Basic Medical Sciences Zhengzhou University 450001 Zhengzhou Henan China
- Collaborative Innovation Center of Henan Province for Cancer Chemoprevention Zhengzhou University 450001 Zhengzhou Henan China
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100
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Tsutsumi T, Saitoh A, Kasai T, Chu M, Karanjit S, Nakayama A, Namba K. Synthesis and evaluation of 1,1,7,7-tetramethyl-9-azajulolidine (TMAJ) as a highly active derivative of N,N-dimethylaminopyridine. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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