CONVERGENT, ENANTIOSELECTIVE SYNTHESIS OF THE NOVEL FURANODITERPENE (-TAONIANONE THROUGH FACIALLY SELECTIVE CHIRAL OLEFIN-KETENE [2+2]-CYCLOADDITION())

(+)-Taonianone, an unusual diterpene from the brown alga Taonia austra lasica, has been enantioselectively prepared through [2+2] cycloadditi on of chloromethylketene with a chiral enol ether.