Allylations of Chelated Enolates Using Dienyl Substrates
作者:Sankar Basak、Uli Kazmaier
DOI:10.1021/ol702865q
日期:2008.2.1
Isomerization-free reactions of dienyl carbonates (1-3) with chelated amino acid ester enolates at -78 degrees C provide important information concerning the mechanism of these dienylations. The formation of regioisomeric products can be explained by competing SN2/SN2' reactions, and the product distribution can be influenced by proper choice of the reaction conditions.
Synthesis of compounds with quaternary carbons is one of the most attractive reactions in the synthetic chemistry. However, there are only a few reports on synthesis of the compounds with a fluoroalkyl group at a quaternary carbon center. Recently, we reported the synthesis of alpha-trifluoromethylated ketones by the reaction of alpha,beta-unsaturated ketones with CF(3)-I using a Rh catalyst. When