Efficient selective catalytic oxidation of benzylic C-H bonds by ZIF-67 under eco-friendly conditions

We report here an efficient, mild and green protocol for the chemoselective oxidization of benzylic C-H bonds. The reactions were carried out with ZIF-67 as heterogeneous catalyst and tert-butyl hydroperoxide as an oxidant. The desired ketones were achieved in moderate to excellent yields at room temperature under solvent-free and open-flask conditions. Notably, the presented method avoids the use of complex catalyst, toxic organic solvent, additives and high temperature. At the same time, the heterogeneous catalyst could be conveniently reused at least six cycles without significantly decreasing yield of desired product. The gram-scale experiments were achieved with excellent yields and provided a modest and effective method for scale up applications. (C) 2017 Published by Elsevier B.V.