1: 1.) O3/O2, 2.) NaOAc, AcOH, Ac2O / 1.) AcOH, cyclohexane, 5 deg C, 2.) from 30 to 40 deg C, 1.5 h 2: p-toluenesulfonic acid / 24 h / Ambient temperature View Scheme

toluene-4-sulfonic acid 24 h; Ambient temperature; Yield given;

1: 90 percent / diisobutylaluminium hydride / diethyl ether; toluene / 1.5 h / -10 °C 2: 100 percent / pyridine / 20 h / 0 °C 3: 1.) CuI / 1.) Et2O, -5 deg C, 40 min, 2.) Et2O, from -5 to 0 deg C, 15 h 4: 95 percent / 10percent aq. HCl / acetone / 6 h 5: 1.) Mg / 1.) THF, 2.) THF, RT, 3 h 6: pyridine / 20 h / 0 °C 7: NaI, Zn / tetrahydrofuran / 3 h / Heating 8: 95 percent / 10percent aq. HCl / acetone / 6 h / 40 °C 9: 95 percent / diisobutylaluminium hydride / diethyl ether; toluene / 1.5 h / -10 °C 10: 75 percent / pyridine View Scheme