title: Regioselective palladium-catalyzed alkylation of allylic halides with benzylic grignard reagents. Two-step synthesis of abietane terpenes and tetracyclic polyprenoid compounds.
abstract: A highly regioselective palladium-catalyzed alpha-alkylation of allylic bromides 1a,c-e and chloride 1b with substituted and unsubstituted benzylic Grignard reagents is reported. The resulting all-trans polyenehomobenzene derivatives were obtained in excellent yields and regioselectivity. These products were easily converted to abietane-type diterpenes (10-12) and tetracyclic polyprenoid compounds (13, 14) through a Lewis acid-promoted cascade polyene cyclization reaction.
authors.affiliation: Max-Planck-Institut für Strahlenchemie, D-45413 Mülheim an der Ruhr, Germany.
authors.forename: Viale
authors.initials: V
authors.lastname: Rosales
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Zambrano
authors.forename: Martin
authors.initials: M
authors.lastname: Demuth