1: 97 percent / conc. H2SO4, NBS / tetrahydrofuran / 1.) -78 deg C, 5 min, 2.) -78 deg C, 5 h 2: 94 percent / NaH / dimethylformamide / 1.) 25 deg C, 30 min, 2.) 25 deg C, 2 h 3: 1.) n-BuLi, 2.) H2 / 2.) 10percent Pd-C 4: 91 percent / DMAP / dioxane / 1 h / 100 °C 5: 76 percent / NaBH4 / ethanol / 0.5 h / 25 °C 6: 43 percent / imidazole / dimethylformamide / 1 h / 100 °C 7: 90 percent / 9-BBN-OTf / CH2Cl2 / 0.25 h / -78 °C 8: LiOH / methanol / 0.17 h / 25 °C 9: 94 percent / aq. LiOH / tetrahydrofuran / 25 °C View Scheme

Multi-step reaction with 4 steps 1: 85 percent / N-iodosuccinimide, H2SO4 / tetrahydrofuran; methanol / 3 h / -78 °C2: 95 percent / NaH / dimethylformamide / 1.) 0 deg C, 45 min, 2.) 25 deg C, 3 h3: 90 percent / Bu3SnH / benzene / 1 h / 70 °C4: 80 percent / Zn, aq. CH3COOH / tetrahydrofuran / 2 h / 70 °C