piperidinium acetate in water 16 h; Ambient temperature;

1: 51 percent / aq. piperidinium acetate / H2O / 16 h / Heating 2: 61 percent / phosphorus pentachloride / 1 h / 120 °C 3: 94 percent / methanol / Heating 4: 62 percent / diisobutylaluminum hydride / tetrahydrofuran / 4 h / 0 °C 5: zinc iodide / 2 h / Ambient temperature 6: lithium aluminum hydride / diethyl ether / 2 h 7: 64 percent / ethanol / 6 h 8: 93 percent / pyridine hydrochloride / 0.17 h / 150 °C 9: 75 percent / H2 / 5 percent Pd/C / methanol; tetrahydrofuran / 760 Torr View Scheme