The PM3 semi-empirical SCF–MO procedure and ab initio theory at the correlated MP2/3-21G level predict both concerted and stepwise pathways for the Beckmann rearrangement of formaldehyde oxime, whereas no concerted pathway exists at the MNDO, AM1, or RHF/3-21G levels.
No takes yet. Share an insight, caveat, or question.
Hunt et al. (1989) studied this question.