C-benzylation of various sodium enolates derived frommethyl malonate, beta-ketoesters, a beta-cyanoester, a beta-cyanosulfone, ketones and a carboxylic ester is reported. Reaction of alkoxydiphenylsulfonium salts formed by treating various benzyl alcohols with diphenyl sulfide bis(trifluoromethanesulfonate) (derived from trifluoromethanesulfonic anhydride and diphenyl sulfoxide) proceeded smoothly, and
A facile one-pot C-benzylation of various sodium enolates derived from methyl malonate, beta-ketoesters, a beta-cyanoester, a beta-cyanosulfone, ketones and a carboxylic ester is reported. Reaction of alkoxydiphenylsulfonium salts formed by treating various benzyl alcohols with diphenyl sulfide bis(trifluoromethanesulfonate) (derived from trifluoromethanesulfonic anhydride and diphenyl sulfoxide) proceeded
Reductive Knoevenagel Condensation with the Zn–AcOH System
作者:Ekaterina M. Budynina、Konstantin L. Ivanov、Mikhail Ya. Melnikov
DOI:10.1055/s-0040-1705940
日期:2021.4
gram-scale one-pot approach to 2-substituted malonates and related structures is developed, starting from commercially available aldehydes and active methylene compounds. The technique combines Knoevenagelcondensation with the reduction of the C=C bond in the resulting activated alkenes with the Zn–AcOH system. The relative ease with which the C=C bond reduction occurs can be traced to the accepting abilities
of electron-deficient alkenes with disilanes in acetonitrile gave silylated alkanes in high yields. The photosilylation occurred in a highly regioselective manner at the position β to the electron-withdrawing groups of the alkenes. With asymmetrically substituted disilanes and polysilanes, silyl groups bearing more bulky substituents were preferentially introduced to the alkenes. The photoreactions were
<b>Electrochemical Dearomatizing Spirocyclization of Alkynes with D</b>imethyl 2-Benzylmalonate<b>s to Spiro[4.5]deca-trienones</b>
作者:Laiqiang Li、Zhong-Wei Hou、Pinhua Li、Lei Wang
DOI:10.1021/acs.joc.2c00939
日期:2022.7.1
dimethyl 2-benzylmalonates for the preparation of spiro[4.5]deca-trienones has been developed. This approach adopts ferrocene (Cp2Fe) as an electrocatalyst to produce carbon-centered radical intermediates from C–H-based malonates, which obviates the forthputting of noble-metal reagents, sacrificial chemical oxidants and 2-bromomalonates. A wide variety of spiro compounds are efficiently prepared with satisfactory