1: triethylamine / tetrahydrofuran; diethyl ether / 3 h / 0 °C 2: 1.) silver benzoate, triethylamine, 2.) sodium hydroxide / 1.) 99percent ethanol, reflux, 1 h 15 min, 2.) methanol, water, 60-65 deg C, 4 h. View Scheme

1: triethylamine / tetrahydrofuran; diethyl ether / 3 h / 0 °C 2: 1.) silver benzoate, triethylamine, 2.) sodium hydroxide / 1.) 99percent ethanol, reflux, 1 h 15 min, 2.) methanol, water, 60-65 deg C, 4 h. 3: 85 percent / CCl4; tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -20 deg C, 30 min, 2.) R.T., 12 h. 4: lithium aluminum hydride / tetrahydrofuran / 12 h / Heating View Scheme