A simple asymmetric synthesis of 2-substituted pyrrolidines from 3-acylpropionic acids
摘要:
The title compounds have been prepared from 3-acylpropionic acids 2 and (-)-R-phenylglycinol in a three-step sequence in > 98% enantiomeric excess. The R group in 2 ultimately becomes the 2-substituent in the chiral pyrrolidine.
A simple asymmetric synthesis of 2-substituted pyrrolidines and 5-substituted pyrrolidinones
作者:Laurence E. Burgess、A. I. Meyers
DOI:10.1021/jo00032a012
日期:1992.3
An efficient procedure for the preparation of the title compounds in high enantiomeric purity has been realized starting from 3-acylpropionic acids. Stereoselective reduction of chiral bicyclic lactams 2a-h, prepared from the corresponding gamma-keto acid and (R)-phenylglycinol, using alane or triethylsilane with titanium tetrachloride provided the N-substituted pyrrolidines and pyrrolidinones, respectively. Subsequent cleavage of the phenylglycinol returned the desired amines and lactams. The enantiomeric purity of these compounds was determined to be > 98% by chiral stationary-phase HPLC.
MEYERS, A. I.;BURGESS, LAURENCE E., J. ORG. CHEM., 56,(1991) N, C. 2294-2296