The Stereocontrolled Construction of the Adjacent Tertiary Carbons by Using the Michael Addition

The stereocontrolled construction of the adjacent tertiary carbons is important in the synthesis of various natural products. By conducting the Michael addition of ester and amide enolates to a, β-unsaturated esters under appropriate reaction conditions, glutaric acid derivatives with definite relative and absolute configuration are prepared. In combination with intramolecular carbon-carbon bond formation, the process is extended to the stereoselective formation of extracyclic chiral centers, and successfully applied to the synthesis of (+)-dehydroiridodiol. Several other approaches to the stereoselective synthesis of adjacent tertiary carbons are also included.