Dehydration of Aldoximes Using PhSe(O)OH as the Pre-Catalyst in Air

PhSe­(O)­OH was found to be a good pre-catalyst for aldoxime dehydrations in open air. Compared with the previously reported (PhSe)₂-H₂O₂ system, it is more stable and milder, affording broader application scopes due to a higher functional group tolerance. The control experiments for mechanism study disclosed that air was the key factor for the reaction to maintain enough concentration of PhSeOH, which should be the real catalytic species.