Copper-Catalyzed Decarboxylative Difluoroalkylation and Perfluoroalkylation of α,β-Unsaturated Carboxylic Acids
作者:Yin-Long Lai、Dian-Zhao Lin、Jing-Mei Huang
DOI:10.1021/acs.joc.6b02613
日期:2017.1.6
Copper-catalyzed decarboxylative difluoroalkylation and perfluoroalkylation of α,β-unsaturatedcarboxylicacids is described. Promoted by dialkyl phosphite, this novel reaction affords fluoroalkylated motifs with excellent stereoselectivity and broad substrate scope under mild reaction conditions from readily available fluoroalkyl iodides and bromides. Preliminary mechanism study suggests that radical
Visible-Light Photocatalytic Decarboxylation of α,β-Unsaturated Carboxylic Acids: Facile Access to Stereoselective Difluoromethylated Styrenes in Batch and Flow
development of synthetic methodologies which provide access to both stereoisomers of α,β-disubstituted olefins is a challenging undertaking. Herein, we describe the development of an operationallysimple and stereoselectivesynthesis of difluoromethylated styrenes via a visible-light photocatalytic decarboxylation strategy using fac-Ir(ppy)3 as the photocatalyst. Meta- and para-substituted cinnamic acids provide
Pathway for the Stereocontrolled <i>Z</i> and <i>E</i> Production of α,α-Difluorine-Substituted Phenyl Butenoates
作者:Wadih Ghattas、Corinna R. Hess、Gilles Iacazio、Renaud Hardré、Judith P. Klinman、Marius Réglier
DOI:10.1021/jo061022s
日期:2006.10.1
and 1b together with the corresponding acids 2a and 2b is described. The procedures involve stereocontrolled additions of •CF2CO2Et to phenylacetylene or β-bromostyrene. Compound 1a is easily obtained by addition of •CF2CO2Et to phenylacetylene via a mechanism where the stereochemistry is controlled by an electron-transfer process to produce predominantly the Z vinyl anion. The product 1b is obtained
描述了纯Z-和E- α,α-二氟-4-苯基-3-丁烯酸乙酯1a和1b以及相应的酸2a和2b的有效制备方法。该程序包括将• CF 2 CO 2 Et立体控制地添加到苯乙炔或β-溴苯乙烯中。化合物1a中很容易被加入得到• CF 2 CO 2的Et到苯乙炔经由其中的立体化学是通过电子转移过程控制,以产生主要为一个机构Ž乙烯基阴离子。产品图1b是通过• CF 2 CO 2 Et通过Z-或E -β-溴苯乙烯的加成消除反应而获得的,该机理是立体化学受中间体构象平衡中的空间因素控制。
The Activation of Carbon−Chlorine Bonds in Per- and Polyfluoroalkyl Chlorides: DMSO-Induced Hydroperfluoroalkylation of Alkenes and Alkynes with Sodium Dithionite
作者:Zheng-Yu Long、Qing-Yun Chen
DOI:10.1021/jo9900937
日期:1999.6.1
omega-dichloroperfluoroalkanes, the similarly stepwise reactions with an alkene is not clean, both bis-adducts and the corresponding omega-hydrides, RCH(2)CH(2)(CF(2))(n)()H as byproducts are also formed. In the absence of alkenes or alkynes, per- and polyfluoroalkyl chlorides can be converted to their sulfinate salts and sulfonyl chlorides.
Copper-mediated regioselective hydrodifluoroalkylation of alkynes
作者:Xiaorui Feng、Xiaoyang Wang、Hongtai Chen、Xiangyang Tang、Minjie Guo、Wentao Zhao、Guangwei Wang
DOI:10.1039/c8ob00256h
日期:——
A highly regioselective copper-mediated hydrodifluoroalkylation of alkynes with ethyl bromodifluoroacetate or bromodifluoroacetamides has been developed. This strategy provides straightforward access to a variety of difluoroalkylated alkenes under mild reaction conditions with low-cost cuprous bromide and metabisulfite as reduction agents. A wide range of alkynes are applicable under these reaction