Chemoselective Rh-Catalyzed Allylic Alkylations of Chelated Enolates using Dienylcarbonates
作者:Saskia Hähn、Uli Kazmaier
DOI:10.1002/ejoc.201100350
日期:2011.7.14
catalyst not only for highly regio- but also chemoselectiveallylicalkylations of chelated enolates. In contrast to Pd-catalyzed reactions, the Rh-catalyzed version shows also a high degree of regioretention and proceeds without isomerization. Allylic substrates with competitive allylic subunits react selectively at the sterically least hindered allylic position, in comparison to Ru-catalyzed processes
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.