1
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Liu X, Shen Y, Lu C, Jian Y, Xia S, Gao Z, Zheng Y, An Y, Wang Y. Visible-light-driven PhSSPh-catalysed regioselective hydroborylation of α,β-unsaturated carbonyl compounds with NHC-boranes. Chem Commun (Camb) 2022; 58:8380-8383. [PMID: 35792097 DOI: 10.1039/d2cc02846h] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A photo-induced transition-metal-free regioselective hydroborylation of α,β-unsaturated carbonyl compounds is developed. The PhSSPh reagent was employed as the photocatalyst, and NHC-BH3 was used as the boron source. This transformation shows a broad substrate scope and provides a wide range of α-borylcarbonyl molecules in good to excellent yields.
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Affiliation(s)
- Xinghua Liu
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yujing Shen
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Cheng Lu
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yongchan Jian
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Shuangshuang Xia
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Zhaoliang Gao
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yihan Zheng
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yuanyuan An
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
| | - Yubin Wang
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, P. R. China.
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2
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Zhang Y, Liao Y, Liu P, Ran Y, Liu X. Radical borylation of vinyl azides with NHC-boranes: divergent synthesis of α-boryl ketones and borylated triazoles. Org Biomol Chem 2022; 20:3550-3557. [PMID: 35411904 DOI: 10.1039/d2ob00076h] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A divergent radical borylation of vinyl azides with N-heterocyclic carbene (NHC) boranes in the presence of tBuSH is described. The protocol enables the divergent synthesis of α-boryl ketones and borylated triazoles with excellent functional group tolerance and a broad substrate scope. Remarkably, this work shows that vinyl azides can serve as unprecedented five-atom synthons for the construction of 1,2,3-triazoles without N2 extrusion.
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Affiliation(s)
- Yifei Zhang
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China.
| | - Yangzhen Liao
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China.
| | - Peijun Liu
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China. .,Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563000, China
| | - Yu Ran
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China.
| | - Xiaozu Liu
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Generic Drug Research Center of Guizhou Province, School of Pharmacy, Zunyi Medical University, Zunyi 563000, China. .,Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563000, China
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3
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Zhao Q, Yao Q, Dou T, Xu T, Zhang J, Chen X. Catalysts Based on the C−H⋅⋅⋅M Weak Interaction: Synthesis, Characterization and Catalytic Application of Bis(pyrazolyl)borate Cu(I) Complexes in Carbene Insertion into Heteroatom Hydrogen Bonds. ChemistrySelect 2022. [DOI: 10.1002/slct.202200552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Qianyi Zhao
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
| | - Qiu‐Yue Yao
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
| | - Ting Dou
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
| | - Ting Xu
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
| | - Jie Zhang
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
| | - Xuenian Chen
- School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials Key Laboratory of Green Chemical Media and Reactions Ministry of Education Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Henan Normal University Xinxiang Henan 453007 China
- College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou Henan 450001 China
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4
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Chen ZL, Empel C, Wang K, Wu PP, Cai BG, Li L, Koenigs RM, Xuan J. Enabling Cyclopropanation Reactions of Imidazole Heterocycles via Chemoselective Photochemical Carbene Transfer Reactions of NHC-Boranes. Org Lett 2022; 24:2232-2237. [PMID: 35274531 DOI: 10.1021/acs.orglett.2c00609] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Herein we report a site-selective cyclopropanation of N-heterocyclic carbene (NHC)-borane complexes via photochemical carbene transfer reactions. By subtle changes to the reaction conditions, this approach can be further extended toward the difunctionalization of NHC-boranes via cyclopropanation and the B-H insertion reaction. Further investigations in photochemical continuous-flow applications and synthetic transformations proved the utility of the method. Theoretical calculations and control experiments were performed to explain the observed selectivity.
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Affiliation(s)
- Ze-Le Chen
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Claire Empel
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Kun Wang
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Pan-Pan Wu
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Bao-Gui Cai
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Lei Li
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China
| | - Rene M Koenigs
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany
| | - Jun Xuan
- Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, College of Chemistry & Chemical Engineering, Anhui University, Hefei, Anhui 230601, China.,Key Laboratory of Structure and Functional Regulation of Hybrid Materials (Anhui University), Ministry of Education, Hefei 230601, China
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5
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Borthakur B, Ghosh B, Phukan AK. The flourishing chemistry of carbene stabilized compounds of group 13 and 14 elements. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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6
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Yang JM, Guo FK, Zhao YT, Zhang Q, Huang MY, Li ML, Zhu SF, Zhou QL. Insertion of Alkylidene Carbenes into B-H Bonds. J Am Chem Soc 2020; 142:20924-20929. [PMID: 33238105 DOI: 10.1021/jacs.0c09596] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We have developed a protocol for insertion of alkylidene carbenes into the B-H bonds of amine-borane adducts, enabling, for the first time, the construction of C(sp2)-B bonds by means of carbene-insertion reactions. Various acyclic and cyclic alkenyl borane-amine adducts were prepared from readily accessible starting materials in good to high yields and were subsequently subjected to a diverse array of functional group transformations. The unprecedented spiro B-N heterocycles prepared in this study have potential utility as building blocks for the synthesis of pharmaceuticals. Preliminary mechanistic studies suggest that insertion of the alkylidene carbenes into the B-H bonds of the amine-borane adducts proceeds via a concerted process involving a three-membered-ring transition state.
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Affiliation(s)
- Ji-Min Yang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Feng-Kai Guo
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yu-Tao Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qiao Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ming-Yao Huang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Mao-Lin Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shou-Fei Zhu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qi-Lin Zhou
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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7
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Qu HJ, Yuan L, Jia CX, Yu HT, Xu H. DFT Investigation of Hydrogen Atom Abstraction from NHC-Boranes by Methyl, Ethyl and Cyanomethyl Radicals-Composition and Correlation Analysis of Kinetic Barriers. Molecules 2020; 25:molecules25194509. [PMID: 33019654 PMCID: PMC7582687 DOI: 10.3390/molecules25194509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/21/2020] [Accepted: 09/29/2020] [Indexed: 11/20/2022] Open
Abstract
Understanding the hydrogen atom abstraction (HAA) reactions of N-heterocyclic carbene (NHC)-boranes is essential for extending the practical applications of boron chemistry. In this study, density functional theory (DFT) computations were performed for the HAA reactions of a series of NHC-boranes attacked by •CH2CN, Me• and Et• radicals. Using the computed data, we investigated the correlations of the activation and free energy barriers with their components, including the intrinsic barrier, the thermal contribution of the thermodynamic reaction energy to the kinetic barriers, the activation Gibbs free energy correction and the activation zero-point vibrational energy correction. Furthermore, to describe the dependence of the activation and free energy barriers on the thermodynamic reaction energy or reaction Gibbs free energy, we used a three-variable linear model, which was demonstrated to be more precise than the two-variable Evans–Polanyi linear free energy model and more succinct than the three-variable Marcus-theory-based nonlinear HAA model. The present work provides not only a more thorough understanding of the compositions of the barriers to the HAA reactions of NHC-boranes and the HAA reactivities of the substrates but also fresh insights into the suitability of various models for describing the relationships between the kinetic and thermodynamic physical quantities.
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Affiliation(s)
- Hong-jie Qu
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education) and School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China; (H.-j.Q.); (L.Y.); (C.-x.J.)
- College of Science, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Lang Yuan
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education) and School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China; (H.-j.Q.); (L.Y.); (C.-x.J.)
| | - Cai-xin Jia
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education) and School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China; (H.-j.Q.); (L.Y.); (C.-x.J.)
| | - Hai-tao Yu
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education) and School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China; (H.-j.Q.); (L.Y.); (C.-x.J.)
- Correspondence: (H.-t.Y.); (H.X.); Tel.: +86-451-86608616 (H.-t.Y.)
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education) and School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China; (H.-j.Q.); (L.Y.); (C.-x.J.)
- Correspondence: (H.-t.Y.); (H.X.); Tel.: +86-451-86608616 (H.-t.Y.)
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8
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Zhang SS, Xie H, Shu B, Che T, Wang XT, Peng D, Yang F, Zhang L. Iridium-catalyzed B-H insertion of sulfoxonium ylides and borane adducts: a versatile platform to α-boryl carbonyls. Chem Commun (Camb) 2020; 56:423-426. [PMID: 31822876 DOI: 10.1039/c9cc08795h] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Iridium-catalyzed boron-hydrogen bond insertion reactions of trimethylamine-borane and sulfoxonium ylides have been demonstrated, furnishing α-boryl ketones in moderate to excellent yields in most cases (51 examples; up to 84%). This practical and scalable insertion reaction showed broad substrate scope, high functional-group compatibility and could be applied in late-stage modification of structurally complex drug compounds. Further synthetic applications were also demonstrated.
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Affiliation(s)
- Shang-Shi Zhang
- Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou, 510006, China.
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9
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Li J, He H, Huang M, Chen Y, Luo Y, Yan K, Wang Q, Wu Y. Iridium-Catalyzed B–H Bond Insertion Reactions Using Sulfoxonium Ylides as Carbene Precursors toward α-Boryl Carbonyls. Org Lett 2019; 21:9005-9008. [PMID: 31689110 DOI: 10.1021/acs.orglett.9b03410] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Jianglian Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Hua He
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Mengyi Huang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Yuncan Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Yi Luo
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Kaichuan Yan
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Qiantao Wang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
| | - Yong Wu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, P. R. China
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10
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Dai W, Geib SJ, Curran DP. Facile Synthesis of α-N-Heterocyclic Carbene-Boryl Ketones from N-Heterocyclic Carbene-Boranes and Alkenyl Triflates. J Am Chem Soc 2019; 141:12355-12361. [DOI: 10.1021/jacs.9b05547] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Wen Dai
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15208, United States
| | - Steven J. Geib
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15208, United States
| | - Dennis P. Curran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15208, United States
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11
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Li T, Zhang J, Cui C. Heterocyclic Carbene‐Catalyzed Hydride Transfer in the Hydroboration of Carbonyl Compounds. CHINESE J CHEM 2019. [DOI: 10.1002/cjoc.201900139] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Tianhao Li
- State Key Laboratory of Elemento‐Organic ChemistryNankai University, 94 Weijin Road Tianjin 300071 China
| | - Jianying Zhang
- State Key Laboratory of Elemento‐Organic ChemistryNankai University, 94 Weijin Road Tianjin 300071 China
| | - Chunming Cui
- State Key Laboratory of Elemento‐Organic ChemistryNankai University, 94 Weijin Road Tianjin 300071 China
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12
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Ren SC, Zhang FL, Xu AQ, Yang Y, Zheng M, Zhou X, Fu Y, Wang YF. Regioselective radical α-borylation of α,β-unsaturated carbonyl compounds for direct synthesis of α-borylcarbonyl molecules. Nat Commun 2019; 10:1934. [PMID: 31036844 PMCID: PMC6488649 DOI: 10.1038/s41467-019-09825-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 04/02/2019] [Indexed: 12/21/2022] Open
Abstract
Organoboron compounds are highly valuable in synthetic chemistry. In particular, α-borylcarbonyl compounds have shown versatile synthetic applications, owing to fruitful chemistries of both the boryl and carbonyl moieties. However, the synthesis of these molecules still remains tedious and time-consuming. Here we report a straightforward and practical route to synthesize α-borylcarbonyl molecules based on a regioselective radical α-borylation of α,β-unsaturated carbonyl compounds. The reaction features unusual α-regioselectivity and high functional-group compatibility. Further synthetic applications of new α-borylated products were also demonstrated. DFT and kinetic studies implicated that the α-regioselectivity of β-aryl-α,β-unsaturated carbonyl compounds was determined by the thermodynamically more favorable radical α-addition step, whereas the formation of α-addition products from β-alkyl-α,β-unsaturated carbonyl compounds was driven by an energetically favored hydrogen atom transfer step. Given that α,β-unsaturated carbonyl compounds can be easily obtained in abundance and variety, this method enjoys great advantages in diverse and economical synthesis of valuable α-borylcarbonyl molecules. α-Borylcarbonyl compounds are versatile synthons in organic synthesis, however their preparation is often tedious. Here, the authors report a regioselective radical α-borylation of α,β-unsaturated carbonyl compounds to afford α-borylcarbonyl molecules with high selectivity and functional group compatibility.
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Affiliation(s)
- Shi-Chao Ren
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Feng-Lian Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Ai-Qing Xu
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Yinuo Yang
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Min Zheng
- Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China
| | - Xiaoguo Zhou
- Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China.
| | - Yao Fu
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China.
| | - Yi-Feng Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, Center for Excellence in Molecular Synthesis of CAS, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026, China. .,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China.
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13
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Chen K, Huang X, Zhang SQ, Zhou AZ, Kan SBJ, Hong X, Arnold FH. Engineered Cytochrome c-Catalyzed Lactone-Carbene B-H Insertion. Synlett 2019; 30:378-382. [PMID: 30930550 PMCID: PMC6436545 DOI: 10.1055/s-0037-1611662] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Previous work has demonstrated that variants of a heme protein, Rhodothermus marinus cytochrome c (Rma cyt c), catalyze abiological carbene boron-hydrogen (B-H) bond insertion with high efficiency and selectivity. Here we investigated this carbon-boron bondforming chemistry with cyclic, lactone-based carbenes. Using directed evolution, we obtained a Rma cyt c variant BOR LAC that shows high selectivity and efficiency for B-H insertion of 5- and 6-membered lactone carbenes (up to 24,500 total turnovers and 97.1:2.9 enantiomeric ratio). The enzyme shows low activity with a 7-membered lactone carbene. Computational studies revealed a highly twisted geometry of the 7membered lactone carbene intermediate relative to 5- and 6-membered ones. Directed evolution of cytochrome c together with computational characterization of key iron-carbene intermediates has allowed us to expand the scope of enzymatic carbene B-H insertion to produce new lactone-based organoborons.
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Affiliation(s)
- Kai Chen
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
| | - Xiongyi Huang
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
| | - Shuo-Qing Zhang
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 31007, P. R. of China
| | - Andrew Z Zhou
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
| | - S B Jennifer Kan
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
| | - Xin Hong
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 31007, P. R. of China
| | - Frances H Arnold
- Division of Chemistry and Chemical Engineering 210-41, California Institute of Technology, Pasadena, CA 91125, USA
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14
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Huang X, Garcia-Borràs M, Miao K, Kan SBJ, Zutshi A, Houk KN, Arnold FH. A Biocatalytic Platform for Synthesis of Chiral α-Trifluoromethylated Organoborons. ACS CENTRAL SCIENCE 2019; 5:270-276. [PMID: 30834315 PMCID: PMC6396380 DOI: 10.1021/acscentsci.8b00679] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Indexed: 05/04/2023]
Abstract
There are few biocatalytic transformations that produce fluorine-containing molecules prevalent in modern pharmaceuticals. To expand the scope of biocatalysis for organofluorine synthesis, we have developed an enzymatic platform for highly enantioselective carbene B-H bond insertion to yield versatile α-trifluoromethylated (α-CF3) organoborons, an important class of organofluorine molecules that contain stereogenic centers bearing both CF3 and boron groups. In contrast to current "carbene transferase" enzymes that use a limited set of simple diazo compounds as carbene precursors, this system based on Rhodothermus marinus cytochrome c (Rma cyt c) can accept a broad range of trifluorodiazo alkanes and deliver versatile chiral α-CF3 organoborons with total turnovers up to 2870 and enantiomeric ratios up to 98.5:1.5. Computational modeling reveals that this broad diazo scope is enabled by an active-site environment that directs the alkyl substituent on the heme CF3-carbene intermediate toward the solvent-exposed face, thereby allowing the protein to accommodate diazo compounds with diverse structural features.
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Affiliation(s)
- Xiongyi Huang
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
| | - Marc Garcia-Borràs
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, California 90095, United States
| | - Kun Miao
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
| | - S. B. Jennifer Kan
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
| | - Arjun Zutshi
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
| | - K. N. Houk
- Department
of Chemistry and Biochemistry, University
of California, Los Angeles, California 90095, United States
| | - Frances H. Arnold
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
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15
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Radcliffe JE, Fasano V, Adams RW, You P, Ingleson MJ. Reductive α-borylation of α,β-unsaturated esters using NHC-BH 3 activated by I 2 as a metal-free route to α-boryl esters. Chem Sci 2018; 10:1434-1441. [PMID: 30809360 PMCID: PMC6354834 DOI: 10.1039/c8sc04305a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 11/17/2018] [Indexed: 11/21/2022] Open
Abstract
Useful α-boryl esters can be synthesized in one step from α,β-unsaturated esters using just a simple to access NHC-BH3 (NHC = N-heterocyclic carbene) and catalytic I2. The scope of this reductive α-borylation methodology is excellent and includes a range of alkyl, aryl substituted and cyclic and acyclic α,β-unsaturated esters. Mechanistic studies involving reductive borylation of a cyclic α,β-unsaturated ester with NHC-BD3/I2 indicated that concerted hydroboration of the alkene moiety in the α,β-unsaturated ester proceeds instead of a stepwise process involving initial 1,4-hydroboration; this is in contrast to the recently reported reductive α-silylation. The BH2(NHC) unit can be transformed into electrophilic BX2(NHC) moieties (X = halide) and the ester moiety can be reduced to the alcohol with the borane unit remaining intact to form β-boryl alcohols. The use of a chiral auxiliary, 8-phenylmenthyl ester, also enables effective stereo-control of the newly formed C-B bond. Combined two step ester reduction/borane oxidation forms diols, including excellent e.e. (97%) for the formation of S-3-phenylpropane-1,2-diol. This work represents a simple transition metal free route to form bench stable α-boryl esters from inexpensive starting materials.
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Affiliation(s)
- James E Radcliffe
- School of Chemistry , University of Manchester , Manchester , M13 9PL , UK .
| | - Valerio Fasano
- School of Chemistry , University of Manchester , Manchester , M13 9PL , UK .
| | - Ralph W Adams
- School of Chemistry , University of Manchester , Manchester , M13 9PL , UK .
| | - Peiran You
- School of Chemistry , University of Manchester , Manchester , M13 9PL , UK .
| | - Michael J Ingleson
- School of Chemistry , University of Manchester , Manchester , M13 9PL , UK .
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16
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Dai W, Geib SJ, Curran DP. Reactions of N-Heterocyclic Carbene Boranes with 5-Diazo-2,2-dimethyl-1,3-dioxane-4,6-dione: Synthesis of Mono- and Bis-hydrazonyl NHC-Boranes. J Org Chem 2018; 83:8775-8779. [PMID: 30004702 DOI: 10.1021/acs.joc.8b01125] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
N-Heterocyclic carbene boranes (NHC-boranes) react with 5-diazo-2,2-dimethyl-1,3-dioxane-4,6-dione at 40 °C in dichloromethane to provide NHC-boryl hydrazone derivatives of 2,2-dimethyl-1,3-dioxane-4,6-dione. These hydrazones disproportionate to bis-hydrazones on treatment with diiodine in dichloromethane at room temperature. The mono- and bis-hydrazones are yellow solids that are stable to chromatography and storage.
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Affiliation(s)
- Wen Dai
- Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States
| | - Steven J Geib
- Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States
| | - Dennis P Curran
- Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States
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17
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Yang JM, Zhao YT, Li ZQ, Gu XS, Zhu SF, Zhou QL. Gold-Catalyzed Oxidative Coupling of Terminal Alkynes and Borane Adducts: Efficient Synthesis of α-Boryl Ketones. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02052] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Ji-Min Yang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yu-Tao Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zi-Qi Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xue-Song Gu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shou-Fei Zhu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qi-Lin Zhou
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China
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18
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Nesterov V, Reiter D, Bag P, Frisch P, Holzner R, Porzelt A, Inoue S. NHCs in Main Group Chemistry. Chem Rev 2018; 118:9678-9842. [PMID: 29969239 DOI: 10.1021/acs.chemrev.8b00079] [Citation(s) in RCA: 508] [Impact Index Per Article: 84.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Since the discovery of the first stable N-heterocyclic carbene (NHC) in the beginning of the 1990s, these divalent carbon species have become a common and available class of compounds, which have found numerous applications in academic and industrial research. Their important role as two-electron donor ligands, especially in transition metal chemistry and catalysis, is difficult to overestimate. In the past decade, there has been tremendous research attention given to the chemistry of low-coordinate main group element compounds. Significant progress has been achieved in stabilization and isolation of such species as Lewis acid/base adducts with highly tunable NHC ligands. This has allowed investigation of numerous novel types of compounds with unique electronic structures and opened new opportunities in the rational design of novel organic catalysts and materials. This Review gives a general overview of this research, basic synthetic approaches, key features of NHC-main group element adducts, and might be useful for the broad research community.
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Affiliation(s)
- Vitaly Nesterov
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Dominik Reiter
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Prasenjit Bag
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Philipp Frisch
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Richard Holzner
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Amelie Porzelt
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
| | - Shigeyoshi Inoue
- Department of Chemistry, WACKER-Institute of Silicon Chemistry and Catalysis Research Center , Technische Universität München , Lichtenbergstrasse 4 , Garching bei München 85748 , Germany
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19
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Allen TH, Horner AR, Geib SJ, Weber SG, Curran DP. Synthesis, Structure, and Acidity Constants of Ligated α-Boryl Acetic Acids. Chemistry 2018; 24:822-825. [PMID: 29207202 DOI: 10.1002/chem.201705754] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Indexed: 11/09/2022]
Abstract
Basic hydrolyses of various ligated α-boryl acetic acid esters provided the first ligated derivatives of the unknown compound boroacetic acid (BH2 CH2 CO2 H). Four monoacids (L-BH2 CH2 CO2 H) and one diacid (L-BH(CH2 CO2 H)2 ) were prepared with N-heterocyclic carbene, amine, and pyridine ligands (L). The stable acids were characterized by X-ray crystallography and acidity constant (pKa ) measurements. They rank among the least acidic of all known carboxylic acids. In turn, their conjugate bases are among the strongest of all carboxylates.
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Affiliation(s)
- Thomas H Allen
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Anthony R Horner
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Steven J Geib
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Stephen G Weber
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Dennis P Curran
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA
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20
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Jennifer Kan SB, Huang X, Gumulya Y, Chen K, Arnold FH. Genetically programmed chiral organoborane synthesis. Nature 2017; 552:132-136. [PMID: 29186119 PMCID: PMC5819735 DOI: 10.1038/nature24996] [Citation(s) in RCA: 198] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 11/02/2017] [Indexed: 12/20/2022]
Abstract
Recent advances in enzyme engineering and design have expanded nature's catalytic repertoire to functions that are new to biology. However, only a subset of these engineered enzymes can function in living systems. Finding enzymatic pathways that form chemical bonds that are not found in biology is particularly difficult in the cellular environment, as this depends on the discovery not only of new enzyme activities, but also of reagents that are both sufficiently reactive for the desired transformation and stable in vivo. Here we report the discovery, evolution and generalization of a fully genetically encoded platform for producing chiral organoboranes in bacteria. Escherichia coli cells harbouring wild-type cytochrome c from Rhodothermus marinus (Rma cyt c) were found to form carbon-boron bonds in the presence of borane-Lewis base complexes, through carbene insertion into boron-hydrogen bonds. Directed evolution of Rma cyt c in the bacterial catalyst provided access to 16 novel chiral organoboranes. The catalyst is suitable for gram-scale biosynthesis, providing up to 15,300 turnovers, a turnover frequency of 6,100 h-1, a 99:1 enantiomeric ratio and 100% chemoselectivity. The enantiopreference of the biocatalyst could also be tuned to provide either enantiomer of the organoborane products. Evolved in the context of whole-cell catalysts, the proteins were more active in the whole-cell system than in purified forms. This study establishes a DNA-encoded and readily engineered bacterial platform for borylation; engineering can be accomplished at a pace that rivals the development of chemical synthetic methods, with the ability to achieve turnovers that are two orders of magnitude (over 400-fold) greater than those of known chiral catalysts for the same class of transformation. This tunable method for manipulating boron in cells could expand the scope of boron chemistry in living systems.
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Affiliation(s)
| | | | - Yosephine Gumulya
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States
| | - Kai Chen
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, MC 210-41, Pasadena, CA 91125, United States
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