ol070447d_si_002.pdf (2.65 MB)

Copper-Catalyzed Cyclization of Steroidal Acylaminoacetylenes:  Syntheses of Novel 11β-Aryl-17,17- spiro[(4‘H,5‘-methylene)oxazol]-Substituted Steroids

Download (2.65 MB)
journal contribution
posted on 10.05.2007, 00:00 by Chunyang Jin, Jason P. Burgess, John A. Kepler, C. Edgar Cook
A variety of novel 11β-aryl-17,17-spiro[(4‘H,5‘-methylene)oxazol]-substituted steroids have been synthesized in moderate to good yields via copper-catalyzed cyclization of acylaminoacetylenes. The best result was obtained with a catalytic amount of CuI in 1:1 benzene−Et3N at 90 °C for 30 min (Ar = 3,4-difluorophenyl; R = ethyl; 97% yield).