1: 2 h / 60 °C 2: 40 percent / KOH / tetrahydrofuran / 1 h / Ambient temperature 3: 1.) DIBAH; 2.) MnO2 / 1.) THF, 0 deg C, 15 min; 2.) Et2O, room temperature, 30 min 4: 43 percent / KOH / tetrahydrofuran / 1 h / 0 °C 5: 1.) DIBAH; 2.) MnO2 / 1.) THF, 0 deg C, 15 min; 2.) Et2O, room temperature, 30 min 6: 2 percent / NaOMe / methanol; dimethylformamide / 3 h / Ambient temperature View Scheme