1: 1.) sodium hydride / 2.) tetrakis(triphenylphosphine)palladium(0) / 1.) THF, room temperature, 30 min, 2.) reflux, 2.5 h 2: 76 percent / tetramethylammonium acetate / hexamethylphosphoric acid triamide / 6 h / 90 - 95 °C 3: disodium hydrogen phosphate, 6percent sodium amalgam / tetrahydrofuran; ethanol / 2.5 h / -20 °C 4: 98 percent / hydrogen / 5percent palladium on barium carbonate / ethanol / 2 h / 1520 Torr / Ambient temperature View Scheme