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.
Lithiation of 2-(1-Chloroethyl)-2-oxazolines: Synthesis of Substituted Oxazolinyloxiranes and Oxazolinylaziridines
Lithiation of 2-(1-chloroethyl)-4,4-dimethyl-2-oxazoline 2 leads to lithiated derivative 3, which is quite stable and can be deuterated, methylated and silylated to give oxazolines 4a-c. The reaction of 3 with carbonyl compounds and imines furnishes good to excellent yields of oxazolinylepoxides 6a-m and aziridines 17a-f, respectively. Methylation and NaBH4 reduction of epoxides 6 afford oxazolidines
Synthesis and lithiation of oxazolinylaziridines: the N-substituent effect
作者:Renzo Luisi、Vito Capriati、Saverio Florio、Peppino Di Cunto、Biagia Musio
DOI:10.1016/j.tet.2005.01.045
日期:2005.3
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.