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.
β-diketones - flavones - thioflavones - thiophosphoryl chloride