Synthesis 2006(7): 1123-1126  
DOI: 10.1055/s-2006-926380
PAPER
© Georg Thieme Verlag Stuttgart · New York

Catalytic Activity of 1,3-Dibromo-5,5-dimethylhydantoin (DBH) in the One-Pot Transformation of N-Arylglycines to N-Arylsydnones in the Presence of NaNO2/Ac2O under Neutral Conditions: Subsequent Bromination of these Sydnones to their 4-Bromo Derivatives

Davood Azarifar*, Hassan Ghasemnejad-Bosra
Department of Chemistry, School of Science, Bu-Ali Sina University, 65174 Hamadan, Iran
Fax: +98(811)8272404; e-Mail: azarifar@basu.ac.ir;
Further Information

Publication History

Received 17 October 2005
Publication Date:
08 March 2006 (online)

Abstract

1,3-Dibromo-5,5-dimethylhydantoin (DBH) has been found to efficiently catalyze the one-pot conversion of various N-arylglycines through N-nitrosation and cyclization to sydnones in combination with NaNO2 and Ac2O in high yields (80-94%) under mild and neutral conditions. Also, it was shown that DBH can conveniently­ promote the bromination of these sydnones to their 4-bromo substituted congeners in excellent yields in DMF at room temperature.