ammonium Nitrite (5). The distillate obtained at 100" C (0.60 torr) was extracted with dichloromethane (20 mL). Evaporation of solvent from the extract left a colorless, crystalline residue of glyoxal dihydrazone (4; 75.1 mg, 0.872 mmol, 53.8%), which was identical by IR, NMR, and melting point with an authentic~ amp1e. l~
