1: 1.) Mg / 1.) THF, 2.) THF, RT, 3 h 2: pyridine / 20 h / 0 °C 3: NaI, Zn / tetrahydrofuran / 3 h / Heating 4: 95 percent / 10percent aq. HCl / acetone / 6 h / 40 °C 5: 95 percent / diisobutylaluminium hydride / diethyl ether; toluene / 1.5 h / -10 °C 6: 75 percent / pyridine View Scheme