Facile Route for Preparation of Benzil Derivatives via Oxidation of Alkenes under Metal-Free Conditions

1,2-Diketones are one of the most important materials in biologically active molecules [1] and are very useful compounds that can easily be transformed into a variety of other chemicals, especially heterocyclic compounds [2]. Among 1, 2- diketones, benzil derivatives also exhibit bioactivities in antitumor applications [3]. Different methods for the synthesis of 1, 2-diketones have been developed, and they mostly involve the oxidation of varioustype of substrates such as olefins, methylene ketones, and alkynes. However, alkenes are cheaper and more easily available than others. Alternatively, the oxidation of stilbenes provides a simple and efficient route to benzil derivatives in both academia and industry.Also, to synthesis of benzil derivatives, a number of catalytic systems have been built in previous years, mainly containing transition metals such as Cu [4], Pd [5], Ru [6] and Mn [7] in combination with oxidants. Here, we report a new green, mild and efficient method for synthesis of benzil derivatives from stilbenes in the presence of TBAI and TBHP as an oxidant system withoutuse of any metal.