Synthesis 2003(9): 1457-1461
DOI: 10.1055/s-2003-40193
SPECIALTOPIC
© Georg Thieme Verlag Stuttgart ˙ New York

Total Regio- and Stereoselective Synthesis of Perhydropyrrolo[3,4-c]pyrazole Derivatives by [3+2] Intramolecular Dipolar Cycloaddition Reaction on Chiral Perhydro-1,3-benzoxazines

Rafael Pedrosa*, Celia Andrés*, Alicia Maestro, Javier Nieto
Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Dr. Mergelina s/n, 47011-Valladolid, Spain
Fax: +34(983)423013; e-Mail: pedrosa@qo.uva.es ;
Further Information

Publication History

Received 28 April 2003
Publication Date:
24 June 2003 (online)

Abstract

Reaction of N-acyl-N′-methyl- or N-acyl-N′-phenylhydrazines with chiral 3-allyl-2-formylperhydro-1,3-benzoxazines form azomethine imines that cyclize to give perhydropyrrolo[3,4-c]pyrazole derivatives. The dipolar cycloaddition was totally regio- and stereoselective yielding a single diastereoisomer. The reaction conditions and the yields of the final compounds are dependent on the substitution pattern of the olefinic bond