Regioselective synthesis of (trifluoromethyl)-β-chloroenones

Article abstract of DOI:10.1016/S0022-1139(96)03523-3

The regioselectivity of the conversion of 1,3-diketones into β-chloroenones can be changed by the appropriate choice of the reagent: reaction with "Vilsmeier's reagent" prepared from POCl₃ and dimethylformamide or treatment of the diketone with the oxalyl chloride in the presence of dimethylformamide.