Radical Tandem Cyclizations by Anodic Decarboxylation of Carboxylic Acids

Abstract

Radical tandem cyclizations are initiated by the Kolbe electrolysis of unsaturated carboxylic acids 4, 18, 23-25 which are prepared in a few steps. The efficiency of the radical tandem cyclization provides a short synthetic sequence to tricyclic products, e.g. angular triquinanes 7, 8, 11, 26-28. In this anodic tandem cyclization, three C-C bonds are formed regio-and stereoselectively in a one-pot reaction by intramolecular addition and intermolecular coupling. The use of different carboxylic acids as starting materials and various coacids gives versatile access to substituted tricyclic compounds.