Generation of Axially Chiral Fluoroallenes through a Copper-Catalyzed Enantioselective β-Fluoride Elimination DOI
Thomas J. O’Connor, Binh Khanh, Jordan Nafie

et al.

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(34), P. 13759 - 13768

Published: Aug. 16, 2021

Herein we report the copper-catalyzed silylation of propargylic difluorides to generate axially chiral, tetrasubstituted monofluoroallenes in both good yields (27 examples >80%) and enantioselectivities (82-98% ee). Compared previously reported synthetic routes chiral allenes (ACAs) from prochiral substrates, a mechanistically distinct reaction has been developed: enantiodiscrimination between enantiotopic fluorides set an axial stereocenter. DFT calculations vibrational circular dichroism (VCD) suggest that β-fluoride elimination alkenyl copper intermediate likely proceeds through syn-β-fluoride pathway rather than anti-elimination pathway. The effects C1-symmetric Josiphos-derived ligand on reactivity enantioselectivity were investigated. Not only does this showcase species (like their alkyl counterparts) can undergo elimination, but be achieved enantioselective fashion.

Language: Английский

Transition‐Metal‐Mediated and ‐Catalyzed C−F Bond Activation by Fluorine Elimination DOI
Takeshi Fujita, Kohei Fuchibe, Junji Ichikawa

et al.

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(2), P. 390 - 402

Published: June 28, 2018

Abstract The activation of carbon–fluorine (C−F) bonds is an important topic in synthetic organic chemistry. Metal‐mediated and ‐catalyzed elimination β‐ or α‐fluorine proceeds under milder conditions than oxidative addition to C−F bonds. initiated from organometallic intermediates having fluorine substituents on carbon atoms β α metal centers, respectively. Transformations through these processes (C−F bond cleavage), which are typically preceded by carbon–carbon (or carbon–heteroatom) formation, have been increasingly developed the past five years as methods. In this Minireview, we summarize applications transition‐metal‐mediated chemistry a historical perspective with early studies systematic recent studies.

Language: Английский

Citations

437
Methodologies and Strategies for Selective Borylation of C–Het and C–C Bonds DOI
Minyan Wang, Zhuangzhi Shi

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

Citations

303
First-Row d-Block Element-Catalyzed Carbon–Boron Bond Formation and Related Processes DOI
Shubhankar Kumar Bose, Lujia Mao,

Laura Kuehn

et al.

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

Citations

238
Recent Advances in Alkenyl sp2 C–H and C–F Bond Functionalizations: Scope, Mechanism, and Applications DOI
Mingzhu Lu, Jeffrey Goh, Manikantha Maraswami

et al.

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

Citations

150
A Copper(I)‐Catalyzed Enantioselective γ‐Boryl Substitution of Trifluoromethyl‐Substituted Alkenes: Synthesis of Enantioenriched γ,γ‐gem‐Difluoroallylboronates DOI

Ryoto Kojima,

Sota Akiyama,

Hajime Ito

et al.

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(24), P. 7196 - 7199

Published: April 27, 2018

Abstract The first catalytic enantioselective γ‐boryl substitution of CF 3 ‐substituted alkenes is reported. A series was treated with a diboron reagent in the presence copper(I)/Josiphos catalyst to afford corresponding optically active γ,γ‐ gem ‐difluoroallylboronates high enantioselectivity. thus obtained products could be readily converted into difluoromethylene‐containing homoallylic alcohols using highly stereospecific allylation reactions.

Language: Английский

Citations

162
Nickel-Catalyzed Enantioselective Reductive Aryl Fluoroalkenylation of Alkenes DOI
Teng Ma,

Yate Chen,

Yuxiu Li

et al.

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(10), P. 9127 - 9133

Published: Sept. 4, 2019

Enantioselective Ni-catalyzed reductive aryl monofluoroalkenylation of alkenes between bromides and gem-difluoroalkenes has been developed. The reaction proceeding under room temperature base-free conditions tolerates a wide range functional groups on both coupling partners. Various synthetically useful oxindoles containing monofluoroalkenyl substituent are obtained in good yields with 85%–95% enantiomeric excess. In addition, the synthetic method can be further applied to late-stage complex biologically active compounds.

Language: Английский

Citations

138
Recent advances in three-component difunctionalization ofgem-difluoroalkenes DOI
Chi Liu, Hao Zeng, Chuanle Zhu

et al.

Chemical Communications, Journal Year: 2020, Volume and Issue: 56(72), P. 10442 - 10452

Published: Jan. 1, 2020

Three-component difunctionalization ofgem-difluoroalkenesviathe generation and transformation of a α-fluoroalkylated carbanion, carbon–metal species, radical, carbocation intermediate.

Language: Английский

Citations

134
Recent Advances in Transition Metal‐Catalyzed Functionalization of gem‐Difluoroalkenes DOI
Suvajit Koley, Ryan A. Altman

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

Citations

133
Activation of the Si–B interelement bond related to catalysis DOI Creative Commons
Jian‐Jun Feng, Wenbin Mao, Liangliang Zhang

et al.

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 50(3), P. 2010 - 2073

Published: Dec. 16, 2020

Covering the past seven years, this review comprehensively summarises latest progress in preparation and application of Si–B reagents, including discussion relevant reaction mechanisms.

Language: Английский

Citations

128
Copper-Catalyzed Carboxylation of C–F Bonds with CO2 DOI

Si‐Shun Yan,

Dongshan Wu, Jian‐Heng Ye

et al.

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(8), P. 6987 - 6992

Published: July 5, 2019

An effective Cu-catalyzed selective formal carboxylation of C–F bonds with an atmospheric pressure CO2 is reported. A variety gem-difluoroalkenes, gem-difluorodienes, and α-trifluoro-methyl alkenes show high reactivity selectivity for this ipso monocarboxylation. Under mild conditions, diverse important α-fluoroacrylic acids α,α-difluorocarboxylates are obtained in good-to-high yields. Moreover, operationally simple protocol features good functional group tolerance, readily scalable, the resulting products converted into bioactive α-fluorinated carbonyl compounds, indicating potential application biochemistry drug discovery. Mechanistic studies reveal that fluorinated boronate esters might be vital intermediates transformation.

Language: Английский

Citations

126