1: 1) hydrazine hydrate, 2) KOH / 1) diethylene glycol, 130 deg C, 1 h, 2) diethylene glycol, 130 deg C, 2 h, then 160 deg C, 3 h 2: 1) TiCl4, 2) hydroxylamine hydrochloride, pyridine / 1) CH2Cl2, 0 deg C, 30 min, 2) ethanol, reflux, 2 h 3: 73 percent / acetic anhydride / 2 h / Heating 4: 2.5 g / Ni-Al alloy, 75percent formic acid / 8 h / Heating View Scheme

1: 57 percent / H2SO4, KNO3 / 1 h / 0 °C 2: 1) hydrazine hydrate, 2) KOH / 1) diethylene glycol, 180 deg C, 2) reflux, overnight View Scheme

1: Py / ethanol / Heating 2: NaBH4, BF3-Et2O / 1,2-dimethoxy-ethane 3: benzene View Scheme

(i) NaBH3CN, NaOAc, Na2SO4, MeOH, Et2O, (ii) aq. KOH, EtOH, tBuOH; Multistep reaction;