Methodologies and Strategies for Selective Borylation of C–Het and C–C Bonds

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(15), P. 7348 - 7398

Published: June 29, 2020

Organoborons have emerged as versatile building blocks in organic synthesis to achieve molecular diversity and carboxylic acid bioisosteres with broad applicability drug discovery. Traditionally, these compounds are prepared by the substitution of Grignard/lithium reagents electrophilic boron species Brown hydroboration. Recent developments provided new routes for efficient preparation organoborons applying reactions using chemical feedstocks leaving groups. As compared previous methods that used halides (I, Br, Cl), direct borylation less reactive C–Het C–C bonds has become highly important get efficiency functional-group compatibility. This Review aims provide a comprehensive overview this topic, including (1) C–F bond borylation, (2) C–O (3) C–S (4) C–N (5) borylation. Considerable attention is given strategies mechanisms involved. We expect will inspire chemists discover more transformations expand field.

Language: Английский

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First-Row d-Block Element-Catalyzed Carbon–Boron Bond Formation and Related Processes

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(21), P. 13238 - 13341

Published: Oct. 7, 2021

Organoboron reagents represent a unique class of compounds because their utility in modern synthetic organic chemistry, often affording unprecedented reactivity. The transformation the carbon–boron bond into carbon–X (X = C, N, and O) stereocontrolled fashion has become invaluable medicinal agrochemistry, natural products chemistry as well materials science. Over past decade, first-row d-block transition metals have increasingly widely used catalysts for formation bond, traditionally catalyzed by expensive precious metals. This recent focus on alternative enabled growth fundamental methods organoboron chemistry. review surveys current state-of-the-art use element-based bonds.

Language: Английский

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Copper-Catalyzed Borylative Difunctionalization of π-Systems

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(19), P. 11578 - 11622

Published: Aug. 25, 2020

Organoboronates represent a cornerstone functional group in modern synthesis owing to their unique reactivity and divergent synthetic capability. Copper catalysis has become one of the most powerful methods stereoselectively install boron across diverse π-systems. Additionally, this method affords tremendous versatility enabled by difunctionalization π-system addition an electrophile. This review covers known electrophiles intercept catalytic intermediates borylative strategies that have been reported up end May 2020.

Language: Английский

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Recent Advances in Alkenyl sp² C–H and C–F Bond Functionalizations: Scope, Mechanism, and Applications

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(24), P. 17479 - 17646

Published: Oct. 14, 2022

Alkenes and their derivatives are featured widely in a variety of natural products, pharmaceuticals, advanced materials. Significant efforts have been made toward the development new practical methods to access this important class compounds by selectively activating alkenyl C(sp2)–H bonds recent years. In comprehensive review, we describe state-of-the-art strategies for direct functionalization sp2 C–H C–F until June 2022. Moreover, metal-free, photoredox, electrochemical also covered. For clarity, review has divided into two parts; first part focuses on currently available using different alkene as starting materials, second describes bond easily accessible gem-difluoroalkenes material. This includes scope, limitations, mechanistic studies, stereoselective control (using directing groups well metal-migration strategies), applications complex molecule synthesis where appropriate. Overall, aims document considerable advancements, current status, emerging work critically summarizing contributions researchers working fascinating area is expected stimulate novel, innovative, broadly applicable functionalizations coming

Language: Английский

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Photochemical and electrochemical strategies in C–F bond activation and functionalization

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 9(3), P. 853 - 873

Published: Dec. 7, 2021

The recent advances in photochemical or electrochemical C–F bond activation and functionalization have been summarized discussed.

Language: Английский

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Recent Advances in Transition Metal‐Catalyzed Functionalization of gem‐Difluoroalkenes

Israel Journal of Chemistry, Journal Year: 2020, Volume and Issue: 60(3-4), P. 313 - 339

Published: March 1, 2020

gem-Difluorinated alkenes are readily accessible building blocks that can undergo functionalization to provide a broad spectrum of fluorinated and non-fluorinated products. Herein, we review recent (since 2017) transition metal-catalyzed transformations these specialized summarize general reactivity patterns reactions. Many reactions net C-F bond deliver monofluorinated These typically proceed through β-fluoro alkylmetal intermediates eliminate β-fluoride monofluoroalkene A second series exploit coinage metal fluorides add F- the gem-difluorinated alkene, further delivers trifluoromethyl-containing In stark contrast, few in "fluorine-retentive processes" difluoromethylene-based

Language: Английский

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Catalyzing the Hydrodefluorination of CF₃-Substituted Alkenes by PhSiH₃. H• Transfer from a Nickel Hydride

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(10), P. 4793 - 4799

Published: Jan. 14, 2020

The hydrodefluorination of CF3-substituted alkenes can be catalyzed by a nickel(II) hydride bearing pincer ligand. catalyst loading as low 1 mol%. gem-Difluoroalkenes containing number functional groups formed in good to excellent yields radical mechanism initiated H• transfer from the nickel hydride. relative reactivity various substrates supports proposed mechanism, does TEMPO trapping experiment.

Language: Английский

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Direct Synthesis of Multi(boronate) Esters from Alkenes and Alkynes via Hydroboration and Boration Reactions

ACS Catalysis, Journal Year: 2020, Volume and Issue: 11(1), P. 1 - 18

Published: Dec. 10, 2020

Multi(boronate) esters have been attracting increasing attention as versatile building blocks for the succinct and precise synthesis of complex molecules. However, there are a limited number efficient synthetic procedures available. In this respect, direct multiboration alkenes alkynes is undoubtedly an ideal route their synthesis. During past 30 years, catalytic systems based on transition-metals, organophosphines, bases, even catalyst-free systems, with heat or light irradiation straightforward preparation from developed. different numbers (up to 4) positional relationships adjacent boron moieties were obtained, which summarized discussed herein.

Language: Английский

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Design and Synthesis of WJ-Phos, and Application in Cu-Catalyzed Enantioselective Boroacylation of 1,1-Disubstituted Allenes

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(8), P. 6890 - 6895

Published: June 28, 2019

The highly enantioselective copper-catalyzed three-component boroacylation of 1,1-disubstituted allenes is reported by using a class chiral ligands (WJ-Phos), delivering various functionalized organoboron compounds bearing an all-carbon stereocenter in moderate to good yields with high enantioselectivities. WJ-Phos ferrocene-derived sulfinamide phosphine ligand and can be easily synthesized gram-scale from readily available starting materials short steps. salient features this reaction include yields, enantioselectivities, synthesis, diverse synthetic transformations, the development new ligand.

Language: Английский

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A Boron Activating Effect Enables Cobalt-Catalyzed Asymmetric Hydrogenation of Sterically Hindered Alkenes

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(8), P. 3923 - 3930

Published: Feb. 2, 2020

Unsymmetric 1,1-diboryl alkenes bearing one -[BPin] (BPin = pinacolatoboryl) and -[BDan] (BDan 1,8-diaminonaphthalatoboryl) substituent each were hydrogenated in high yield enantioselectivity using C1-symmetric pyridine(diimine) (PDI) cobalt complexes. High activities stereoselectivities observed with an array of 2-alkyl-, 2-aryl-, 2-boryl-substituted alkenes, giving rise to enantioenriched diborylalkane building blocks. Systematic study substrate effects identified competing steric electronic demands the key activating role boron substituents, whereby sterically unencumbered boronates such as -[BDan], -[BCat] (BCat catecholatoboryl), -[Beg] (Beg ethylene glycolatoboryl) promote hydrogenation trisubstituted by enabling irreversible α-boron-directed insertion pathways achieve otherwise challenging hydrogenations alkenes. Deuterium-labeling studies support pathway generating a chiral intermediate two different substituents bound same carbon.

Language: Английский

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