A mild and efficient CAN mediated oxidation of Morita–Baylis–Hillman adducts of 5-methyl-N-alkylisatin to 5-formyl-N-alkylisatin

A simple, mild and efficient CAN mediated oxidation of Morita–Baylis–Hillman adducts of 5-methyl-N-alkylisatins 1a–13a to 5-formyl-N-alkylisatins 1b–13b under ambient reaction conditions is reported. Simple and isomerized 5-methyl-N-alkylisatin derivatives 1–4 have also been tested and failed to provide the corresponding formylated products. A plausible reaction mechanism has been proposed.