1: 87 percent / pyridine / ethanol / 2 h / Heating 2: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 3: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C 4: HF; anisole / 1 h / 0 °C 5: 505 mg / NaOH / H2O; ethanol / 1 h / 20 °C View Scheme

1: 87 percent / pyridine / ethanol / 2 h / Heating 2: 80 percent / BH3*THF / tetrahydrofuran / 3.5 h / Heating 3: 75 percent / sodium cyanoborohydride; HCl / methanol / 24 h / 20 °C View Scheme