Synthesis of Enantiomerically Pure α-Substituted Propargylic Amines by Reaction of Organoaluminum Reagents with Oxazolidines
作者:J. Blanchet、M. Bonin、L. Micouin、H.-P. Husson
DOI:10.1021/jo0003706
日期:2000.10.1
Various oxazolidines prepared in two steps from (R)-phenylglycinol react at 0 degrees C with dialkyl-alkynylalane-triethylamine complexes in the presence of trimethylaluminum in high yield and diastereoselectivity. Enantiomerically pure primary alpha-substituted propargylamines cah be easily obtained in two steps after removal of ferrocenylmethyl protective group under smooth acidic conditions and oxidative cleavage of the chiral appendage.
Isomerization of Chiral Non-Racemic α-Substituted Propargylic Amines to Terminal Acetylenes
Various α-substituted propargylamines, prepared in three steps from (R)-phenylglycinol, are readily isomerized at 0 °C with KAPA to form terminal acetylenic amines, without any detectable epimerization of the chiral center, as already observed for propargyl alcohols. Enantiomerically pure primary α-substituted alkynylamines can be easily obtained in two steps after removal of the ferrocenylmethyl protective