1: 98 percent / N2H4*H2O, aq. H2SO4 / ethanol / 2 h / Heating 2: 78 percent / Na2HPO4, 5percent Na/Hg / methanol / 2 h View Scheme

1: 93 percent / NH2OH*HCl, 10percent aqueous sodium hydroxide / ethanol / 0.33 h / Heating 2: 96 percent / disodium hydrogenphosphate, 5percent sodium amalgam / methanol / 2 h View Scheme

1: 60 percent / NH2OH*HCl, tributylamine / ethanol / Heating 2: 60 percent / toluene-p-sulphonic acid monohydrate / ethanol / 3 h / Heating 3: 98 percent / disodium hydrogenphosphate, 5percent sodium amalgam / methanol / 2 h View Scheme

sulfuric acid; hydrazine hydrate in ethanol 2 h; Heating;