Anodic cyclization reactions and the synthesis of (-)-crobarbatic acid

A synthesis of (-)-crobarbatic acid is reported along with the first use of a vinyl-substituted ketene dithioacetal as a coupling partner for an anodic cyclization reaction. The use of the vinyl-substituted ketene dithioacetal enables the construction of a cyclic product having a tetra substituted carbon with a relative stereochemistry opposite to that originally obtained from the cyclization. (c) 2008 Elsevier Ltd. All rights reserved.