摘要 |
An improved process for the production of 1-dialkyl-amino-ethyl-6-aryl-4H-s-triazolo[4,3-a][1,4]benzodiazepines of the formula II: <IMAGE> II wherein R1 is alkyl of 1 to 3 carbon atoms, inclusive; wherein R2 is hydrogen, methyl or phenyl; wherein the ring A is unsubstituted, or monosubstituted with fluoro, chloro, bromo, nitro, trifluoromethyl or methylthio; and wherein Ar is phenyl; o-chlorophenyl; o-fluorophenyl; 2,6-difluorophenyl or 2-pyridyl, is carried out by reacting a compound of the Formula I: <IMAGE>I wherein ring A, Ar and R2 are defined as above, with a dialkylmethyleneammonium salt in the presence of a reactive carboxylic acylating agent. |