Abstract

A method for the oxygenation of tertiary C-H bonds of N-alkylamidines and N-(2-alkylaryl)amidines is described that utilizes the CuBr·SMe(2)/2,2'-bipyridine catalytic system under an O(2) atmosphere and provides dihydrooxazoles and 4H-1,3-benzoxazines. The oxygen atom is incorporated from atmospheric molecular oxygen during the present process.