Synthesis and some heterocyclization reactions of new diethyl (1,1-difluoro-3,3-dicyano-2-trifluoromethylallyl)phosphonate and ethyl 3,3-dicyano-2-[(diethoxyphosphoryl)difluoromethyl]acrylate

A new CF₂X-analogue of 1,1-bis(trifluoromethyl)-2,2-dicyanoethylene (X = P(O)(OEt)₂), diethyl (1,1-difluoro-3,3-dicyano-2-trifluoromethylallyl)phosphonate, has been synthesized from diethoxyphosphoryl pentafluoroacetone 1. A similar phosphoryl analogue of ethyl 3,3-dicyano-2-trifluoromethylacrylate, ethyl 3,3-dicyano-2-(diethoxyphosphoryl)difluoromethyl]acrylate, has been obtained from ethyl 3-(diethoxyphosphoryl)-3,3-difluoro-2-oxopropionate 2. By heterocyclization of these new ethylenes with 3-methyl-2-pyrazoline-5-ones, 3(5)-aminopyrazoles, dimedone, 2-aminopyridines, 1-aryl-3-methyl-5-aminopyrazoles, 1,3,3-trimethylisoquinolines, as well as by condensation with anilines and ketones, the difluoromethylphosphonate-substituted derivatives of 1,4-dihydropyrano2,3-c]pyrazole, 4,5-dihydropyrazolo1,5-a]pyrimidine, 5,6,7,8-tetrahydro-4H-chromene, 2H-pyrido1,2-a]pyrimidine, 4,7-dihydro-1H-pyrazolo3,4-b]pyridine, 1,4-dihydropyridine, 4,5,6,7-tetrahydro-1H-1]pyrindine, 1,4,5,6,7,8-hexahydroquinoline, and 6,7-dihydro-2H-pyrido2,1-a]isoquinoline have been obtained in one stage.