Copper-Catalyzed Reaction of Trifluoromethylketones with Aldehydes via a Copper Difluoroenolate
作者:Ryohei Doi、Masato Ohashi、Sensuke Ogoshi
DOI:10.1002/anie.201508266
日期:2016.1.4
A copper‐catalyzed reaction of easily accessible α,α,α‐trifluoromethylketones with various aldehydes affords difluoro‐methylene compounds in the presence of diboron and NaOtBu. The key process of the reaction is the formation of a copperdifluoroenolate by 1,2‐addition of a borylcopper intermediate to α,α,α‐trifluoromethylketones and subsequent β‐fluoride elimination. Mechanistic studies including
易催化的α,α,α-三氟甲基酮与各种醛的铜催化反应在存在二硼和NaO t Bu的情况下提供了二氟亚甲基化合物。该反应的关键过程是通过向α,α,α-三氟甲基酮中添加1,2硼基铜中间体并随后消除β-氟来形成二氟烯酸铜。还描述了包括可能的阴离子醇铜中间体的分离和表征在内的机理研究。
Synthesis of 2,2-Difluoro-3-hydroxy-1,4-diketones via an HFIP-Catalyzed Mukaiyama Aldol Reaction of Glyoxal Monohydrates with Difluoroenoxysilanes
A novel efficient HFIP-catalyzed synthesis of structurally diverse 2,2-difluoro-3-hydroxy-1,4-diketone derivatives from readily available glyoxalmonohydrates and difluoroenoxysilanes is described. This convenient protocol is induced by the distinctive fluorine effect of the reactants and the fluoroalcohol catalyst, which represents the first application of fluoroalcohol catalysis in a Mukaiyama aldol
The α,α-difluoro-β-hydroxyketone skeleton is an important pharmacodynamic structure in the synthesis study of pharmaceuticals. Herein, we describe a novel iron mediated Reformatsky reaction of iododifluoroacetophenones with aldehydes, which offers a relatively more economical and environment friendly route for the construction of α,α-difluoro-β‑hydroxyl ketone with good yield. In addition, iron shows