Synthesis 2005(15): 2544-2548  
DOI: 10.1055/s-2005-872077
PAPER
© Georg Thieme Verlag Stuttgart · New York

Base-Catalyzed, Efficient Synthesis of 5-Substituted 3,6-Dihydro-7H-1,2,3-triazolo[4,5-d]pyrimidin-7-ones

Jun-Feng Zhao, Chang Xie, Ming-Wu Ding*, Hong-Wu He*
Key Laboratory of Pesticide & Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, 430079, P. R. China
Fax: +86(27)67862041; e-Mail: mwding@mail.ccnu.edu.cn;
Further Information

Publication History

Received 28 March 2005
Publication Date:
22 July 2005 (online)

Abstract

The carbodiimides 2, obtained from aza-Wittig reactions of iminophosphorane 1 with aromatic isocyanates, reacted with secondary amines or ROH to give 5-dialkylamino or 5-alkoxy 7H-1,2,3-triazolo[4,5-d]pyrimidin-7-ones 4 in the presence of a catalytic amount of EtONa in a mixed solvent (CH2Cl2-ROH). Reactions of 2 with phenols in presence of catalytic potassium carbonate in MeCN gave 5-aryloxy-7H-1,2,3-triazolo[4,5-d]pyrimidin-7-ones 4 in satisfactory yields.