1: 93 percent Turnov. / aq. K2CO3 / methanol / 2.5 h / 0 °C 2: 85 percent / pyridine / toluene / 0.5 h / 0 °C 3: 95 percent / 4-(dimethylamino)pyridine / CH2Cl2 / 0.5 h / 25 °C 4: tetrahydrofuran; cyclohexane / 15 h / -78 °C 5: 94 percent Turnov. / NaBH4 / methanol / 3 h / 25 °C 6: 86 percent Turnov. / NaN(SiMe3)2 / tetrahydrofuran / 0.5 h / 0 °C 7: 80 percent / HF*pyridine / tetrahydrofuran / 1.25 h / 25 °C View Scheme

sodium tetrahydroborate; copper(I) bromide 1.) EtOH, 15 min, room temperature, 2.) EtOH, 30 min; Yield given. Multistep reaction. Yields of byproduct given;