Chiral Acetal-Initiated Asymmetric Pentacyclization. Enantioselective Synthesis of 18.alpha.(H)-Oleananes
作者:Paul V. Fish、William S. Johnson、Garth S. Jones、Fook S. Tham、Rudolph K. Kullnig
DOI:10.1021/jo00100a009
日期:1994.10
Fluorine-assisted asymmetric pentacyclization of (S,S)-acetal 3 gave 18 alpha(H)-oleanane 28b as the major product in 59% isolated yield (86.5% de) and with retention of the fluorine atom at C13.
An application of the trost reaction to the stereoselective synthesis of trans-tetrasubstituted fluoroalkenes
作者:Paul V. Fish、S. Pulla Reddy、Cheol H. Lee、William S. Johnson
DOI:10.1016/s0040-4039(00)74700-9
日期:1992.12
The coupling of beta-fluoroallylic acetates (1) with stabilised ester-enolates (3), in the presence of catalytic palladium(0), gave tetrasubstituted fluoroalkenes (2) in good yield and with generally satisfactory trans-stereoselectivity.