Palladium-Catalyzed Polycyclizations of Enediynes: A Convenient One-Step Synthesis of Polyfunctional Angularly Bisanellated Benzene Derivatives¹

Variously substituted 2-bromotetradec-1-ene-6,12-diynes 9a-d, 10-oxa derivative 5, and 4-oxa derivatives 7a,b cleanly cyclize to highly substituted, bisanellated benzene derivatives 10a-d (2,3,6,7,8,9-hexahydro-1H-benz[e]indenes), 6, and 8a,b (1,2,4,7,8,9-hexahydrocyclopenta[f][2]benzopyrans) under palladium catalysis using Heck-type reaction conditions.