Synthesis 2011(1): 30-32  
DOI: 10.1055/s-0030-1258343
© Georg Thieme Verlag Stuttgart ˙ New York

Preparation of Thioflavones via Thiophosphoryl Chloride Mediated Cyclodehydration and Thionation of 1-(2-Hydroxyphenyl)-3-arylpropane-1,3-diones

Manorama Vimal, Uma Pathak*, Lokesh Kumar Pandey, Malladi V. S. Suryanarayana
Synthetic Chemistry Division, Defence Research & Development Establishment, Gwalior (MP) 474 002, India
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Further Information

Publication History

Received 30 September 2010
Publication Date:
30 November 2010 (online)


A simple and convenient one-pot strategy for the preparation of thioflavones from 1,3-diketones is described. Cyclodehydration of a range of β-diketones and thionation of the resulting flavones was achieved using thiophosphoryl chloride (PSCl3) which serves as both a catalyst and thionating agent.


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