Oxidation of Secondary Amines with NiSO4-K2S2O8
The catalytic system consisting of NiSO4 and K2S2O8 has been found to be effective for the oxidation of secondary amines to imines. 1,2,3,4-Tetrahydroisoquinoline was oxidized to 3,4-dihydroisoquinoline as the main product with a small amount of isoquinoline. N-Benzylaniline gave N-benzylideneaniline and a N-N coupling dimer.