Synthesis of Stereodefined Polysubstituted Olefins. 1. Sequential Intermolecular Reactions Involving Selective, Stepwise Insertion of Pd(0) into Allylic and Vinylic Halide Bonds. The Stereoselective Synthesis of Disubstituted Olefins1

Palladium-catalyzed allylic substitution and cross-coupling reactions have been combined into a sequential procedure to provide a range of disubstituted olefin products starting from two-, three-, and four-carbon common olefin templates. Diverse application of this template strategy is demonstrated in a variety of model studies and in a parallel synthesis (combinatorial) approach to prepare an allylic amine molecular library. An approach toward the preparation of astaxanthin beta-D-diglucoside, an interesting antioxidant whose total synthesis has yet to be reported, using the olefin-template approach is also discussed.