Palladium-catalyzed intramolecular allylic alkylation reaction in marine natural product synthesis: Enantioselective synthesis of (+)-methyl pederate, a key intermediate in syntheses of mycalamides

Article abstract of DOI:10.1021/jo9805246

A novel preparation of (+)-methyl pederate (4), a key intermediate in syntheses of mycalamides (1), marine natural products from a New Zeland sponge of the genus Mycale, is described. The key step involves palladium- catalyzed intramolecular allylic alkylation of the carbonate 21, derived from (+)-(4R,5R,E)-5-(tert-butyldimethylsiloxy)-4-methyl-2-hexenol (13), yielding lactones 5 in 87% yield. Demethoxycarbonylation of the cyclization products 5 and further functional group transformations led to (+)-methyl pederate (4).