1: 99 percent / DIBAL / CH2Cl2 / -78 °C 2: 96 percent / DABCO / W(CO)6 / tetrahydrofuran / 65 °C / Irradiation 3: Bu4NF / tetrahydrofuran 4: Et3N; DMAP / CH2Cl2 5: 71 percent / PPh3; HBr / toluene / 6 h 6: 98 percent / DIBAL / CH2Cl2 / -78 °C 7: DABCO / W(CO)6 / tetrahydrofuran / 65 °C / Irradiation 8: Et3N; DMAP / CH2Cl2 9: PPh3; HBr / CHCl3 10: (NH4)HF2; N-methylpyrrolidine / dimethylformamide / 70 °C 11: NaOMe / methanol View Scheme