Synthesis 2007(8): 1251-1260  
DOI: 10.1055/s-2007-965987
SPECIALTOPIC
© Georg Thieme Verlag Stuttgart · New York

Enantioselective Intramolecular Copper-Catalyzed Aziridination of Sulfamates

Audrey Estéoule, Fernando Durán, Pascal Retailleau, Robert H. Dodd*, Philippe Dauban*
Institut de Chimie des Substances Naturelles, CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France
Fax: +33(1)69077247; e-Mail: robert.dodd@icsn.cnrs-gif.fr; e-Mail: philippe.dauban@icsn.cnrs-gif.fr;
Further Information

Publication History

Received 6 February 2007
Publication Date:
12 March 2007 (online)

Abstract

Intramolecular copper-catalyzed aziridination of sulfamates occurs in very good yields of up to 86% and in up to 84% ee in the presence of (4S,4′S)-2,2′-(propane-2,2-diyl)bis(4-tert-butyl-4,5-dihydro-1,3-oxazole). The resulting aziridines undergo smooth ring opening with different types of nucleophiles in an SN2-type process.

16

At this stage of the experimental work, preliminary investigations of the nucleophilic ring opening of aziridine 4a with benzylamine revealed that it occurs without loss of stereochemical information. No trace of the cis-isomer of the aziridine ring-opened product was observed, while the ee of the latter matched the ee of the aziridine 4a. According to subsequent experiments (vide infra) and Du Bois’s work (see ref. 13f), the reaction is believed to occur by an SN2 process. This result was used to derivatize aziridines 4b-j by reaction with benzylamine in order to determine the enantioselectivity of the asymmetric intramolecular aziridination of sulfamates 2b-j.

19

Estéoule, A.; Dodd, R. H.; Dauban, P. unpublished results.

21

‘Collect’ data collection software; Nonius, B. V.; 1999.