Methylhydrazine → HCID 12515151, compound

Participants

Reaction Steps

A suspension of 8.6 g. (0.03 mole) of 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepine-2-thione (I) (prepared as in U.S. Pat. No. 3,422,091) in 600 ml. of methanol; is treated with 5.53 g. (0.12 mole) of methylhydrazine (II) and stirred at room temperature for about 2.5 hours. A vigorous stream of nitrogen is bubbled through the mixture during this period to remove liberated hydrogen sulfide. The mixture is concentrated under vacuum to a small volume, diluted with ice water and extracted with chloroform. The extract is washed with cold, dilute sodium chloride solution, dried with sodium sulfate and concentrated under vacuum. The residue is chromatographed on 400 g. of silica gel with a mixture of 1.5% methanol-98.5% chloroform. The product is crystallized on a rotary evaporator at about 25° C. by replacing the chloroform of a methanolchloroform solution, first with ethyl acetate and then with Skellysolve B. The yields of 7-chloro-2-(1-methylhydrazino)-5-phenyl-3H-1,4-benzodiazepine (III) are 5.07 g. having a melting point of 166.6° to 173° C. and 0.52 g. having a melting point of 175° to 176° C. The analytical sample is recrystallized from ethyl acetate-Skellysolve B having a melting point of 178.5° to 179.5° C.; ultraviolet (EtOH) end absorption, λmax. 232mμ (ε=21,400), 269 (18,300), 352 (2920); infrared absorption (Nujol) 3290, 3180 cm-1 (NH), 1645, 1590, 1575, 1565 (C=N/C=C).

Provenance & Evidence