Reactions of β-alkoxyvinyl trifluoromethyl ketones.: The synthesis of N-[1-aryl-3-oxo-4,4,4-trifluoro-1-buten-1-yl]-o-phenylenediamines and 4-aryl-2-trifluoromethyl-3H-1,5-benzodiazepines

A series of five N-[1-aryl-3-oxo-4,4,4-trifluoro-1-buten-1-yl]-o-phenylenediamines 2 [CF3COCH=C(R)NH-o-PhNH2], where R=Ph, 4-MePh, 4-BrPh, 4-ClPh, 4-OMePh from the reaction of beta-aryl-beta-methoxyvinyl trifluoromethyl ketones 1 with o-phenylenediamine was prepared and isolated in good yield (59-71%). Another series of five 4-aryl-2-trifluoromethyl-3H-1,5-benzodiazepines 3, where aryl=Ph, 4-MePh, 4-BrPh, 4-ClPh, 4-OMePh was also obtained in an one-step reaction from ketones 1 by an intramolecular cyclization reaction with o-phenylenediamine under mild acid conditions in good yields (60-77%).