1: 54 percent / KOH / diethyl ether; methanol / 3 h 2: 70 percent / pyridine / CH2Cl2 3: 77 percent / hydrazine hydrate / CH2Cl2 / 2 h 4: 60 percent / Na2SO4 / CH2Cl2 / 2 h 5: CH2Cl2 / 48 h 6: 26 percent / benzene; various solvent(s) / 72 h / 110 °C View Scheme

potassium hydroxide in methanol; diethyl ether 3 h;