1
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Ju G, Huang Z, Zhao Y. Trialkoxysilane-Induced Iridium-Catalyzed para-Selective C-H Bond Borylation of Arenes. Nat Commun 2024; 15:2847. [PMID: 38565860 PMCID: PMC10987550 DOI: 10.1038/s41467-024-47205-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 03/22/2024] [Indexed: 04/04/2024] Open
Abstract
An ideal approach for the construction of aryl boron compounds is to selectively replace a C-H bond in arenes with a C-B bond, and controlling regioselectivity is one of the most challenging aspects of these transformations. Herein, we report an iridium-catalyzed trialkoxysilane protecting group-assisted regioselective C-H borylation of arenes, including derivatives of benzaldehydes, acetophenones, benzoic acids, benzyl alcohols, phenols, aryl silanes, benzyl silanes, and multi-functionalized aromatic rings are all well tolerated and gave the para -selective C-H borylation products in a short time without the requirement of inert gases atmosphere. The site-selective C-H borylation can be adjustable by installing the developed trialkoxysilane protecting group on different functional groups on one aromatic ring. Importantly, the preparation process of the trialkoxychlorosilane is efficient and scalable. Mechanistic and computational studies reveal that the steric hindrance of the trialkoxysilane protecting group plays a key role in dictating the para-selectivity.
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Affiliation(s)
- Guodong Ju
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Zhibin Huang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Yingsheng Zhao
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, 453000, China.
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2
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Liu DY, Han J, Liu K, Cheng Y, Tan H, Yang X, Li W, Xie J. Dinuclear Gold-Catalyzed para-Selective C-H Arylation of Undirected Arenes by Noncovalent Interactions. Angew Chem Int Ed Engl 2023; 62:e202313122. [PMID: 37707123 DOI: 10.1002/anie.202313122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/07/2023] [Accepted: 09/14/2023] [Indexed: 09/15/2023]
Abstract
The regioselectivity of C-H functionalization is commonly achieved by directing groups, electronic factors, or steric hindrance, which facilitate the identification of reaction sites. However, such strategies are less effective for reactants such as simple monofluoroarenes due to their relatively low reactivity and the modest steric demands of the fluorine atom. Herein, we present an undirected gold-catalyzed para-C-H arylation of a wide array of monofluoroarenes using air-stable aryl silanes and germanes at room temperature. A high para-regioselectivity (up to 98 : 2) can be realized by utilizing a dinuclear dppm(AuOTs)2 (dppm=bis(diphenylphosphino)methane) as the catalyst and hexafluorobenzene as the solvent. This provides a general and practical protocol for the concise construction of structurally diverse para-arylated monofluoroarenes through C-H activation manner. It features excellent functional group tolerance and a broad substrate scope (>80 examples). Besides, this strategy is also robust for other simple monosubstituted arenes and heteroarenes. Our mechanistic studies and theoretical calculations suggest that para-C-H selectivity arises from highly electrophilic and structurally flexible dinuclear Ar-Au(III)-Au(I) species, coupled with noncovalent interaction induced by hexafluorobenzene.
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Affiliation(s)
- Duan-Yang Liu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Kai Liu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Yaohang Cheng
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Hairen Tan
- National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210023, China
| | - Xiaoliang Yang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Weipeng Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
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3
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Yu IF, Wilson JW, Hartwig JF. Transition-Metal-Catalyzed Silylation and Borylation of C-H Bonds for the Synthesis and Functionalization of Complex Molecules. Chem Rev 2023; 123:11619-11663. [PMID: 37751601 DOI: 10.1021/acs.chemrev.3c00207] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
The functionalization of C-H bonds in organic molecules containing functional groups has been one of the holy grails of catalysis. One synthetically important approach to the diverse functionalization of C-H bonds is the catalytic silylation or borylation of C-H bonds, which enables a broad array of downstream transformations to afford diverse structures. Advances in both undirected and directed methods for the transition-metal-catalyzed silylation and borylation of C-H bonds have led to their rapid adoption in early-, mid-, and late-stage of the synthesis of complex molecules. In this Review, we review the application of the transition-metal-catalyzed silylation and borylation of C-H bonds to the synthesis of bioactive molecules, organic materials, and ligands. Overall, we aim to provide a picture of the state of art of the silylation and borylation of C-H bonds as applied to the synthesis and modification of diverse architectures that will spur further application and development of these reactions.
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Affiliation(s)
- Isaac F Yu
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Jake W Wilson
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - John F Hartwig
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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4
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Stehrer P, Spannenberg A, Hapke M. Atroposelective Ir-Catalyzed C-H Borylation of Phthalazine Heterobiaryls. J Org Chem 2023; 88:14222-14226. [PMID: 37751525 PMCID: PMC10563123 DOI: 10.1021/acs.joc.3c01534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Indexed: 09/28/2023]
Abstract
The atroposelective iridium-catalyzed borylation of menthyloxy-substituted phthalazine heterobiaryls with diborons is reported. Utilizing [Ir(OMe)(COD)]2/2-aminopyridine as a rarely used efficient catalyst system, the heterobiaryls were selectively borylated in the 2-position of the carbocycle, exclusively yielding only one of the atropisomers, depending on the substitution of the phthalazine with (+)-menthyl or (-)-menthyl moieties. Exemplary further functionalization of a borylated atropisomer demonstrated that nickel-catalyzed Suzuki-Miyaura cross-coupling with an aryl halide was able to provide stereoretention to a certain degree (up to 75% de).
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Affiliation(s)
- Paul Stehrer
- Institute
for Catalysis (INCA), Johannes Kepler University
Linz (JKU), Altenberger
Strasse 69, 4040 Linz, Austria
| | - Anke Spannenberg
- Leibniz
Institute for Catalysis e.V. (LIKAT), Albert-Einstein-Strasse 29a, 18069 Rostock, Germany
| | - Marko Hapke
- Institute
for Catalysis (INCA), Johannes Kepler University
Linz (JKU), Altenberger
Strasse 69, 4040 Linz, Austria
- Leibniz
Institute for Catalysis e.V. (LIKAT), Albert-Einstein-Strasse 29a, 18069 Rostock, Germany
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5
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Diversification of pharmaceutical molecules via late-stage C(sp2)–H functionalization. GREEN SYNTHESIS AND CATALYSIS 2023. [DOI: 10.1016/j.gresc.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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6
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Antenucci A, Bonomo M, Ghinato S, Blangetti M, Dughera S. Design of a New Chiral Deep Eutectic Solvent Based on 3-Amino-1,2-propanediol and Its Application in Organolithium Chemistry. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238566. [PMID: 36500673 PMCID: PMC9738533 DOI: 10.3390/molecules27238566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/02/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
A chiral glycerol derivative, namely 3-amino-1,2-propanediol, was employed for as the hydrogen bond donor (HBD) in the design of a new deep eutectic solvent (DES) with choline chloride acting as the hydrogen bond acceptor (HBA). The novel mixture was characterized and unambiguously classified as a DES. Furthermore, its synthetic usefulness was demonstrated in the room-temperature n-butyllithium-addition under air to carbonyl compounds and benzyl chloride. In some cases, pure products (100% conversion) were obtained by a simple extractive work-up in up to 72% isolated yield, thus suggesting the potential practical usefulness of this procedure as a green alternative to the classical Schenk procedure in volatile organic solvents for the synthesis of tertiary alcohols. The chirality of the HBD, bearing an interesting basic primary amino group, is an intriguing feature currently under investigation for further exploitation.
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Affiliation(s)
- Achille Antenucci
- Department of Chemistry, Università degli Studi di Torino, Via Pietro Giuria 7, 10125 Torino, Italy
- Centro Ricerche per la Chimica Fine s.r.l. for Silvateam s.p.a., Via Torre 7, 12080 San Michele Mondovì, Italy
- Correspondence: (A.A.); (M.B.); (S.D.)
| | - Matteo Bonomo
- Department of Chemistry, Università degli Studi di Torino, Via Pietro Giuria 7, 10125 Torino, Italy
- NIS Interdepartmental Centre and INSTM Reference Centre, Università degli Studi di Torino, Via Gioacchino Quarello 15/a, 10125 Torino, Italy
- Correspondence: (A.A.); (M.B.); (S.D.)
| | - Simone Ghinato
- Department of Chemistry, Università degli Studi di Torino, Via Pietro Giuria 7, 10125 Torino, Italy
| | - Marco Blangetti
- Department of Chemistry, Università degli Studi di Torino, Via Pietro Giuria 7, 10125 Torino, Italy
| | - Stefano Dughera
- Department of Chemistry, Università degli Studi di Torino, Via Pietro Giuria 7, 10125 Torino, Italy
- Correspondence: (A.A.); (M.B.); (S.D.)
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7
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Segawa Y, Nagase M, Saito Y, Kato K, Itami K. C-H Borylation of Arenes: Steric-controlled <i>Para</i>-selectivity and Application to Molecular Nanocarbons. J SYN ORG CHEM JPN 2022. [DOI: 10.5059/yukigoseikyokaishi.80.994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | - Mai Nagase
- Department of Structural Molecular Science, SOKENDAI
| | - Yutaro Saito
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo
| | - Kenta Kato
- Department of Applied Chemistry, Waseda University
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8
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Haldar C, Bisht R, Chaturvedi J, Guria S, Hassan MMM, Ram B, Chattopadhyay B. Ligand- and Substrate-Controlled para C–H Borylation of Anilines at Room Temperature. Org Lett 2022; 24:8147-8152. [DOI: 10.1021/acs.orglett.2c03188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Chabush Haldar
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Ranjana Bisht
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| | - Jagriti Chaturvedi
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| | - Saikat Guria
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| | - Mirja Md Mahamudul Hassan
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| | - Bali Ram
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Buddhadeb Chattopadhyay
- Department of Biological & Synthetic Chemistry, Center of Biomedical Research, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
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9
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Veth L, Grab HA, Dydio P. Recent Trends in Group 9 Catalyzed C–H Borylation Reactions: Different Strategies To Control Site-, Regio-, and Stereoselectivity. SYNTHESIS-STUTTGART 2022. [DOI: 10.1055/a-1711-5889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
AbstractOrganoboron compounds continue contributing substantially to advances in organic chemistry with their increasing role as both synthetic intermediates and target compounds for medicinal chemistry. Particularly attractive methods for their synthesis are based on the direct borylation of C–H bonds of available starting materials since no additional pre-functionalization steps are required. However, due to the high abundance of C–H bonds with similar reactivity in organic molecules, synthetically useful C–H borylation protocols demand sophisticated strategies to achieve high regio- and stereoselectivity. For this purpose, selective transition-metal-based catalysts have been developed, with group 9 centered catalysts being among the most commonly utilized. Recently, a multitude of diverse strategies has been developed to push the boundaries of C–H borylation reactions with respect to their regio- and enantioselectivity. Herein, we provide an overview of approaches for the C–H borylation of arenes, alkenes, and alkanes based on group 9 centered catalysts with a focus on the recent literature. Lastly, an outlook is given to assess the future potential of the field.1 Introduction1.1 Mechanistic Considerations1.2 Selectivity Issues in C–H Borylation1.3 Different Modes of Action Employing Directing Group Strategies in C–H Borylation1.4 Scope and Aim of this Short Review2 Trends in C–H Borylation Reactions2.1 Photoinduced Catalysis2.2 Transfer C–H Borylation2.3 Lewis Acid Mediated C–H Borylation2.4 Directed Metalation2.5 Miscellaneous C–H Borylation Reactions2.6 Electrostatic Interactions2.7 Hydrogen Bonding3 Conclusion and Outlook
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10
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Bisht R, Haldar C, Hassan MMM, Hoque ME, Chaturvedi J, Chattopadhyay B. Metal-catalysed C-H bond activation and borylation. Chem Soc Rev 2022; 51:5042-5100. [PMID: 35635434 DOI: 10.1039/d1cs01012c] [Citation(s) in RCA: 72] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Transition metal-catalysed direct borylation of hydrocarbons via C-H bond activation has received a remarkable level of attention as a popular reaction in the synthesis of organoboron compounds owing to their synthetic versatility. While controlling the site-selectivity was one of the most challenging issues in these C-H borylation reactions, enormous efforts of several research groups proved instrumental in dealing with selectivity issues that presently reached an impressive level for both proximal and distal C-H bond borylation reactions. For example, in the case of ortho C-H bond borylation reactions, innovative methodologies have been developed either by the modification of the directing groups attached with the substrates or by creating new catalytic systems via the design of new ligand frameworks. Whereas meta and para selective C-H borylations remained a formidable challenge, numerous innovative concepts have been developed within a very short period of time by the development of new catalytic systems with the employment of various noncovalent interactions. Moreover, significant advancements have occurred for aliphatic C(sp3)-H borylations as well as enantioselective borylations. In this review article, we aim to discuss and summarize the different approaches and findings related to the development of directed proximal ortho, distal meta/para, aliphatic (racemic and enantioselective) borylation reactions since 2014. Additionally, considering the C-H borylation reaction as one of the most important mainstream reactions, various applications of this C-H borylation reaction toward the synthesis of natural products, therapeutics, and applications in materials chemistry will be summarized in the last part of this review article.
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Affiliation(s)
- Ranjana Bisht
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Chabush Haldar
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Mirja Md Mahamudul Hassan
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Md Emdadul Hoque
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Jagriti Chaturvedi
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
| | - Buddhadeb Chattopadhyay
- Center of Bio-Medical Research, Division of Molecular Synthesis & Drug Discovery, SGPGIMS Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India.
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12
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Shreiber ST, Puchall GI, Vicic DA. Transformation of brucine into trifluoromethyl neobrucine using the homoleptic nickel catalyst [Ni(CF3)4]2−. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.153795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Pabst TP, Quach L, MacMillan KT, Chirik PJ. Mechanistic Origins of Regioselectivity in Cobalt-Catalyzed C(sp 2)-H Borylation of Benzoate Esters and Arylboronate Esters. Chem 2021; 7:237-254. [PMID: 33718656 DOI: 10.1016/j.chempr.2020.11.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Synthetic and mechanistic investigations into the C(sp2)-H borylation of various electronically diverse arenes catalyzed by bis(phosphine)pyridine (iPrPNP) cobalt complexes are reported. Borylation of various benzoate esters and arylboronate esters gave remarkably high selectivities for the position para to the functional group; in both cases, this regioselectivity was found to override the ortho to fluorine regioselectivity previously reported for (iPrPNP)Co borylation catalysts which arises from thermodynamic control of C(sp2)-H oxidative addition. Mechanistic studies support two distinct pathways that result in para-to-ester and para-to-boronate ester regioselectivity by thermodynamic and kinetic control, respectively, of C(sp2)-H oxidative addition. Borylation of a particularly electron-deficient fluorinated arylboronate ester resulted in acceleration of C(sp2)-H oxidative addition and concomitant inversion of regioselectivity, demonstrating that subtle changes in the relative rates of individual steps of the catalytic cycle can enable unique and switchable site selectivities.
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Affiliation(s)
- Tyler P Pabst
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Linda Quach
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | | | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.,Lead Contact
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14
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Arevalo R, Pabst TP, Chirik PJ. C(sp 2)-H Borylation of Heterocycles by Well-Defined Bis(silylene)pyridine Cobalt(III) Precatalysts: Pincer Modification, C(sp 2)-H Activation and Catalytically Relevant Intermediates. Organometallics 2020; 39:2763-2773. [PMID: 32831451 PMCID: PMC7440285 DOI: 10.1021/acs.organomet.0c00382] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Well-defined bis(silylene)pyridine cobalt(III) precatalysts for C(sp2)-H borylation have been synthesized and applied to the investigation of the mechanism of the catalytic borylation of furans and pyridines. Specifically, [( Ar SiNSi)CoH3]·NaHBEt3 ( Ar SiNSi = 2,6-[EtNSi(NtBu)2CAr]2C5H3N, Ar = C6H5 (1-H 3 ·NaHBEt 3 ), 4-MeC6H4 (2-H 3 ·NaHBEt 3 )) and trans-[( Ar SiNSi)Co(H)2BPin] (Ar = C6H5 (1-(H) 2 BPin), 4-MeC6H4 (2-(H) 2 BPin), Pin = pinacolato) were prepared and employed as single component precatalysts for the C(sp2)-H borylation of 2-methylfuran, benzofuran and 2,6-lutidine. The cobalt(III) precursors, 2-H 3 ·NaHBEt 3 and 2-(H) 2 BPin also promoted C(sp2)-H activation of benzofuran, yielding [(ArSiNSi)CoH(Bf)2] (Ar = 4-MeC6H4, 2-H(Bf) 2 , Bf = 2-benzofuranyl). Monitoring the catalytic borylation of 2-methylfuran and 2,6-lutidine by 1H NMR spectroscopy established the trans-dihydride cobalt(III) boryl as the catalyst resting state at low substrate conversion. At higher conversion two distinct pincer modification pathways were identified, depending on the substrate and the boron source.
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Affiliation(s)
- Rebeca Arevalo
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Tyler P Pabst
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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