Copper-catalyzed cyclization of steroidal acylaminoacetylenes: syntheses of novel 11beta-aryl-17,17- spiro[(4'H,5'-methylene)oxazol]-substituted steroids.
A variety of novel 11beta-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 degrees C for 30 min (Ar = 3,4-difluorophenyl; R = ethyl; 97% yield).
Jin
Chunyang
C
Organic and Medicinal Chemistry, Science and Engineering Group, Research Triangle Institute, Research Triangle Park, NC 27709, USA. cjin@rti.org
Burgess
Jason P
JP
Kepler
John A
JA
Cook
C Edgar
CE
D000114:Acetylene / Q000737:chemistry*; D000215:Acylation; D000586:Amination; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D003500:Cyclization; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D015394:Molecular Structure; D010080:Oxazoles / Q000737:chemistry*; D045167:Progesterone Congeners / Q000138:chemical synthesis / Q000737:chemistry; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013256:Steroids / Q000138:chemical synthesis / Q000737:chemistry*
D010080:Oxazoles; D045167:Progesterone Congeners; D013141:Spiro Compounds; D013256:Steroids; D003300:Copper; D000114:Acetylene