Synthesis and lithiation of oxazolinylaziridines: the N-substituent effect
摘要:
The preparation of N-substituted oxazolinylaziridines and their deprotonation to afford the corresponding aziridinyllithiums is described. The chemical and configurational stability of the lithiated species depends on the N-substituent on the aziridine ring. The trapping with carbonyl compounds of (R*,S*) configurated oxazolinylaziridines is an interesting route for the preparation of functionalised alpha,beta-aziridino-gamma-lactones. (c) 2005 Elsevier Ltd. All rights reserved.
Aziridinyllithiums 4a and 4b, which are stable at low temperature, can be generated by deprotonation of 3a and 3b. Oxazolinyl aziridines 5a-j and 6a-b have been prepared by the reaction of oxazolinyl aziridinyllithiums 4a and 4b with electrophiles. Aziridines 6c and 6d were, instead, synthesized by a Darzens-like reaction from 2-(1-chloroethyl)-2-oxazoline 1b. (C) 1999 Elsevier Science Ltd. All rights reserved.