Synthesis 2008(9): 1397-1403  
DOI: 10.1055/s-2008-1072514
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Pyrazinothienopyrimidine Derivatives by the Application of the Intramolecular and Intermolecular Aza-Wittig Reaction/Heterocyclization

Gerardo Blanco, José M. Quintela*, Carlos Peinador*
Departamento de Química Fundamental, Facultad de Ciencias, Universidad de A Coruña, 15071 A Coruña, Spain
Fax: +34(981)167000; e-Mail: jqqoqf@udc.es; e-Mail: capeveqo@udc.es.;
Further Information

Publication History

Received 23 November 2007
Publication Date:
18 March 2008 (online)

Abstract

Pyrazino[2′,3′:4,5]thieno[3,2-d]pyrimidine derivatives 6 were synthesized by the intermolecular aza-Wittig reaction of N-heteroaryl phosphazene derivatives with carboxylic acid chlorides. The heterocyclization occurs via imidoyl chloride intermediates derived from phosphazenes 4a,b, obtained in a one-step process from α-azidothieno[2,3-b]pyrazine carboxylic acid 3. Moreover, cyclic pyrazinothienopyrimidines were prepared, in a two-step procedure, from amides and azidothienopyrazine-α-carbonyl chloride using an intramolecular aza-Wittig heterocyclization reaction strategy.

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Crystallographic data (excluding structure factors) for 6b and 9a have been deposited with the Cambridge Crystallographic Data Center as supplementary publication numbers 6b: CCDC 668435, and 9a: CCDC 668436. Copies of the data may be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK (fax: +44 1223 33603 or e-mail: deposit@ccdc.cam.ac.uk).