1: molecular sieves 3A, pyridine / 72 h / Ambient temperature 2: 1.) p-toluenesulfonyl chloride, 2.) H2O / 1.) pyridine, 0 deg C, 15 h, 2.) overnight 3: 94 percent / K2CO3 / methanol / 3 h / Ambient temperature 4: 90 percent / BH3*THF / tetrahydrofuran / 2 h / Heating 5: 91 percent / Jones reagent / acetone / 0.33 h / 0 °C 6: 71 percent / base / acetone View Scheme