C 2 -Symmetrical hemiaminal ethers and diamines with a piperazine core were synthesized starting from Seebach’s oxazolidinone. The new methodology is based on the dimerization of α-amino aldehydes to bicyclic bishemiaminal ethers, followed by reduction to the corresponding diamines. Several enantiopure piperazine derivatives bearing either methyl or bulky groups including isopropyl and aryl at the
An improved method of oxazolidinone hydrolysis in the asymmetric synthesis of α-alkylprolines
作者:Michael J. Genin、Paul W. Baures、Rodney L. Johnson
DOI:10.1016/s0040-4039(00)73294-1
日期:1994.7
An improvement in Seebach's method for the synthesis of alpha-alkylprolines is reported wherein the hydrolysis of the chiral oxazolidinone 2 is performed on a suspension of silica gel in MeOH/H2O. Following hydrolysis, the pure alpha-alkylproline can he obtained by filtration thereby avoiding a tedious ion exchange purification.