Download PDF
Synthesis 2008(12): 1879-1882  
DOI: 10.1055/s-2008-1067035
PAPER
© Georg Thieme Verlag Stuttgart · New York

A New, Easy Access to the 6-Aminoperhydro-1,4-diazepine Scaffold under Ultrasound and Microwave Irradiation

Alessandro Bargea, Silvia Füzerováb, Dharita Upadhyayaa, Davide Garellaa, Silvio Aimeb, Lorenzo Teic, Giancarlo Cravotto*a
a Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Via P. Giuria 9, 10235 Torino, Italy
Fax: +39(011)6707687; e-Mail: giancarlo.cravotto@unito.it;
b Dipartimento di Chimica IFM, Università di Torino, Via P. Giuria 7, 10125 Torino, Italy
c Dipartimento di Scienze dell’Ambiente e della Vita, Università del Piemonte Orientale, Via Bellini 25/G, 25100 Alessandria, Italy
Further Information

Publication History

Received 11 December 2007
Publication Date:
29 April 2008 (online)

    Permissions and Reprints All articles of this category

Abstract

A novel, efficient, and rapid synthesis of the 6-amino­perhydro-1,4-diazepine scaffold is reported. It was promoted by microwave or sequential ultrasound/microwave irradiation under solvent-free conditions or in solution. Protected ethylenediamine derivatives and N-Boc-serinol dimesylate underwent rapid cyclization to give 6-aminoperhydro-1,4-diazepine derivatives in excellent yields and with high selectivity, whereas the same reaction failed or gave negligible yields under conventional heating. Cesium or potassium ions catalyzed the ring closure by coordinating the sulfon­amide groups. All relevant work reported to date in the literature mostly concern about the syntheses of either 1H-tetrahydro-1,4-diazepine-2,5-dione or substituted 1,4-benzodiazepines, while the few published procedures for the preparation of 6-aminoperhydro-1,4-diazepines involved several steps, required long reaction times and afforded low yields. By the present method, access to 6-aminoperhydro-1,4-diazepines becomes much easier and faster.

Key words

heterocycles - synthesis - catalysis - cyclizations - ligands - ring closure