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