Selective benzylic C-H monooxygenation mediated by iodine oxides.

A method for the selective monooxdiation of secondary benzylic C-H bonds is described using an -oxyl catalyst and a hypervalent iodine species as a terminal oxidant. Combinations of ammonium iodate and catalytic -hydroxyphthalimide (NHPI) were shown to be effective in the selective oxidation of -butylbenzene directly to 1-phenylbutyl acetate in high yield (86%). This method shows moderate substrate tolerance in the oxygenation of substrates containing secondary benzylic C-H bonds, yielding the corresponding benzylic acetates in good to moderate yield.