An efficient and generally applicable protocol for decarboxylative coupling of α,α‐difluoroarylacetic acids with ethynylbenziodoxolone (EBX) reagents has been developed, affording α,α‐difluoromethylated alkynes bearing various functional groups in moderate to excellent yields. Remarkably, this potassium persulfate (K2S2O8)‐promoted reaction employs water as solvent under transition metal‐free conditions
已经开发出一种有效且普遍适用的方案,用于将α,α-二氟代芳酸与乙炔基苯并恶唑酮(EBX)试剂进行脱羧偶联,从而以中等至极好的收率提供带有各种官能团的α,α-二氟甲基化炔烃。值得注意的是,这种过硫酸钾(K 2 S 2 O 8)促进的反应在无过渡金属的条件下将水用作溶剂,从而为α,α-二氟甲基化炔烃提供了绿色的合成方法。
Synthesis of Difluoroalkylated Arenes by Hydroaryldifluoromethylation of Alkenes with α,α-Difluoroarylacetic Acids under Photoredox Catalysis
作者:Bin Yang、Xiu-Hua Xu、Feng-Ling Qing
DOI:10.1021/acs.orglett.6b03092
日期:2016.11.18
A visble-light-induced hydroaryldifluoromethylation of alkenes with α,α-difluoroarylacetic acids for preparation of difluoroalkylated arenes has been developed. This reaction proceeds through the hypervalent iodine reagent promoted decarboxylation and subsequent radical hydroaryldifluoromethylation.
Easy Access to Difluoromethylene-Containing Arene Analogues through Palladium-Catalysed C-H Olefination
作者:Changdong Shao、Guangfa Shi、Yanghui Zhang
DOI:10.1002/ejoc.201600954
日期:2016.11
An efficient palladium-catalyzed ortho C−H olefination of α,α-difluorophenylacetic acidderivatives using 8-aminoquinoline as the bidentate directing group has been developed. A range of olefinated arenes can be synthesized in a concise way. This reaction provides an easy and straightforward access to a panel of difluoromethylated arene analogues in moderate to good yields with a satisfactory tolerance
Silver-Catalyzed Decarboxylative Alkynylation of α,α-Difluoroarylacetic Acids with Ethynylbenziodoxolone Reagents
作者:Fei Chen、A. Stephen K. Hashmi
DOI:10.1021/acs.orglett.6b01188
日期:2016.6.17
A decarboxylating alkynylation of α,α-difluoroarylacetic acids with ethynylbenziodoxolone reagents is reported. AgNO3 serves as the catalyst and K2S2O8 as the oxidant. A series of functional groups were tolerated, and moderate to good yields were obtained.
报道了用乙炔基苯并恶唑啉酮试剂对α,α-二氟芳基酸进行脱羧烷基化。AgNO 3用作催化剂,K 2 S 2 O 8用作氧化剂。耐受一系列官能团,并获得中等至良好的产率。