Synthesis of a partially hydrogenated 4H-cyclopenta[def]phenanthrene via a benzannulated enediynyl alcohol

ORGN 768

Bo Wen,, Elbin S. Parbin, and Kung K. Wang. C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506-6045
The benzannulated enediynyl alcohol 3 was synthesized from condensation between indanone 2 and the lithium acetylide derived from 1. The transformation from 3 to 5 involved a reduction followed by a cascade sequence of cyclization reactions. Treatment of 5 with Me3SiI followed by an intramolecular alkylation reaction then provided 7 containing a partially hydrogenated cyclopentaphenanthrene substructure.