1: 76 percent / 4N HCl / tetrahydrofuran / 6 h / Ambient temperature 2: potassium hydroxide / methanol 3: 85 percent / Cu, pyridine / bis-(2-hydroxy-ethyl) ether / 160 - 165 °C 4: 96 percent / boron tribromide / CH2Cl2 / -70 deg C to 20 deg C 5: 74 percent / pyridinium chlorochromate View Scheme