Tandem Addition β-Lithiation−Alkylation Sequence on α,β-Unsaturated Aldehydes
作者:Norma Sbarbati Nudelman、Graciela V. García
DOI:10.1021/jo005698d
日期:2001.2.1
isotopic exchange reactions and trapping of two intermediates, provide clues on the several mechanistic steps of this new reaction. Extended studies revealed that beta-alkyl-substituted alpha,beta-unsaturated aldehydes and aliphatic lithium reagents did not afford good yields of the tandem reaction products, while aromatic lithium reagents gave good results. The aggregation features of the aryllithium
A new reaction between E-cinnamaldehyde and phenyllithium. Mechanistic studies
作者:Norma S. Nudelman、Hernan G. Schulz
DOI:10.1039/a904635f
日期:——
The reaction of phenyllithium (in excess) with E-cinnamaldehyde gives a surprising tandem addition β-alkylation, which can be successfully used for the synthesis of substituted dihydrochalcones. The mechanism by which these unexpected reactions could occur is unknown and experimental and theoretical studies were carried out as a contribution to its understanding.
Platinum-catalyzed Generation of Silylenes from Hydrodisilanes and Their Addition to α,β-Unsaturated Ketones
作者:Kazuhiro Okamoto、Tamio Hayashi
DOI:10.1246/cl.2008.108
日期:2008.1.5
The reaction of hydrodisilanes with α,β-unsaturated ketones in the presence of a platinum catalyst gave high yields of oxasilacyclopentenes, which are probably formed by the addition of silylenes to the enones. Treatment of the oxasilacyclopentenes with methyllithium followed by hydrolysis gave the corresponding β-silyl ketones.
Sodium silylsilanolates are demonstrated as useful silylating reagents for copper-catalysed hydrosilylation of unsaturated bonds via the formation of reactive silylcopper species that can deliver a series of silyl groups.
Nouvelle méthode de création de la liaison silicium-carbone à partir de chlorosilanes VIII. C-silylation d'aldehydes et de cétones α-éthylèniques
作者:R. Calas、J. Dunoguès、M. Bolourtchian
DOI:10.1016/s0022-328x(00)84770-1
日期:1971.1
The trimethylchlorosilane/magnesium/hexamethylphosphoric triamide system reacts with various α-ethylenic aldehydes and ketones to give the 1,4-addition compound of two trimethylsilyl groups. This, after hydrolysis, leads to aldehydes and ketones, C-silylated in β position with respect to the carbonyl group. The corresponding alcohols have been prepared.