Transformations of 2,2-dimethyl-2,4-dihydro-3H-pyrrol-3-on-1-oxide derivatives in the Vilsmeier–Haack reaction conditions

Enhydroxylaminones—2,2-dimethyl-2,4-dihydro-3H-pyrrol-3-on-1-oxides were shown to give various chlorinated products in the Vilsmeier–Haack reaction. The general sequence of the reaction steps is determined and the extent of the reaction was shown to be strongly dependent on the substrate structure.