An effective synthesis of trifluoromethyl-substituted 1,4-dihydropyridines with phosphorus oxychloride / pyridine adsorbed on silica gel

Article abstract of DOI:10.1016/0040-4039(96)00788-5

Treatment of α-alkoxycarbonyl-α,β-unsaturated trifluoromethyl ketones 1 with β-amino-crotonates 2 affords 2-hydroxy-6-methyl-2-trifluoromethyl-1,2,3,4-tetrahydropyridines 3, which undergo dehydration by using phosphorus oxychloride / pyridine adsorbed on