1: sodium hydride; diethyl chlorophosphate / tetrahydrofuran; dimethylformamide / 0.5 h / 0 °C 2: 1.79 g / sodium hydride / dimethylformamide; tetrahydrofuran / 18 h 3: 97 percent / H2 / Pd/C / tetrahydrofuran; ethanol / 2 h 4: BF3*Et2O; t-butyl nitrite / CH2Cl2 / -15 - 5 °C 5: 160 mg / 0.67 h / 130 °C View Scheme

1: 7-nitro-3,4-dihydro-4-methyl-2H-1,4-benzodiazepine-2,5-(1H)-dione With potassium tert-butylate in tetrahydrofuran; N,N-dimethyl-formamide T=0°C; 0.5 h; Inert atmosphere; 2: With diethyl chlorophosphate in tetrahydrofuran; N,N-dimethyl-formamide T=0°C; 0.5 h; Inert atmosphere; 3: isocyano-acetic acid ethyl ester With potassium tert-butylate in tetrahydrofuran; N,N-dimethyl-formamide T=0 - 20°C; 2.5 h; Inert atmosphere;

in N-methyl-acetamide; water; acetic acid

1: sodium hydride; diethyl chlorophosphate / tetrahydrofuran; dimethylformamide / 0.5 h / 0 °C 2: 1.79 g / sodium hydride / dimethylformamide; tetrahydrofuran / 18 h View Scheme