合成路线1

The reaction of 7-chloro-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one (I) with methylamine by means of TiCl4 in refluxing benzene gives 7-chloro-5-(2-fluorophenyl)-2-methylamino-3H-1,4-benzodiazepine (II), which by reaction with NaNO2 in acetic acid is converted into its N-nitroso derivative (III). The treatment of (III) with nitromethane and potassium tert-butoxide in DMF affords 7-chloro-5-(2-fluorophenyl)-2-nitromethylene-2H-1,4-benzodiazepine (IV), which is reduced with H2 over Raney-Ni in THF affording the 2-aminomethyl derivative (V).The acetylation of (V) with acetic anhydride in CH2Cl2 gives the acetamide (VI), which is cyclized with polyphosphoric acid at 150 C yielding 8-chloro-3a,4-dihydro-6-(2-fluorophenyl)-1-methyl-4H-imidazo[1,5-a][1,4]benzodiazepine (VII). The deshydrogenation of (VII) with MnO2 in refluxing toluene affords 8-chloro-6-(2-fluorophenyl)-1-methyl-4H-imidazo[1,5-a][1,4]benzodiazepine (VIII), which is finally treated with maleic acid (A) in hot ethanol.