TY - JOUR
TI - Synthesis of methylene-bridged polycyclic aromatic hydrocarbons: an efficient, double Friedel-Crafts cyclization approach to 11H-benz[bc]aceanthrylene
AU - Thanasis Gimisis
AU - Jeff W. Kampf
AU - Masato Koreeda
JO - The Journal of Organic Chemistry
PY - 1993
VL - 58
TODO - 21
SP - 5858--5861
PB - American Chemical Society (ACS)
SN - null
TODO - 10.1021/jo00073a058
TODO - null
TODO - A five-step synthesis of 3-methylcholanthrene (1) has been achieved starting from 5-methylhomophthalic anhydride and N,N-diethyl-1-naphthamide in 55% overall yield. Treatment of a solution of the preformed lithium enolate of 5-methylhomophthalic anhydride (3) with an equimolar solution of 2-lithio-1-naphthamide (4), followed by acid hydrolysis, provides cleanly the spirobislactone 5 in 80% overall yield. In addition, the synthesis features a unique, highly selective double Friedel-Crafts cyclization of the aryl diacid 2 with PPA to give rise, after acetylation, to keto acetate 6.  1993 America Chemical Society.
ER -