INTRAMOLECULAR CYCLOADDITIONS OF KETENES AND VINYLKETENES TO OLEFINS -III. THE SYNTHESIS OF ANGULAR ANNULATED TRIQUINANE DERIVATIVES
Intramolecular cycloaddition of vinylketene 2 or ketene 6 to an olefin yielded the angular annulated triquinane precursors 4 or 7.The rate enhancement by DMAP in this process was demonstrated.