1: 64 percent / AlH2Cl / diethyl ether / 6 h / Heating 2: 84 percent / SOCl2, pyridine / benzene / 6 h / Heating 3: 51 percent / LiAlH4 / diethyl ether / 12 h / Heating 4: 65 percent / Nafion-H / toluene / 48 h / Heating View Scheme