2-Phenylhydrazinecarboxaldehyde → 1-methyl-2-phenylhydrazine

A solution of N'-phenylformohydrazide (20.59 g) in dry tetrahydrofuran (750 ml) was added dropwise under nitrogen to a stirred suspension of lithium aluminium hydride (10 g) in dry tetrahydrofuran (200 ml), then the mixture was stirred and heated under reflux for 4 hours. The mixture was quenched by the slow dropwise addition of water (10 ml), followed by 5M aqueous sodium hydroxide solution (10 ml), then water (20 ml), then it was filtered, dried (MgSO4) and the solvent removed in vacuo to yield an oil. The oil was dissolved in ether, redried (MgSO4) and the solvent removed in vacuo to yield 1-methyl-2-phenylhydrazine (14.1 g) as a yellow oil.