1: 100 percent / pyridinium dichromate, pyridinium p-toluenesulfonate / CH2Cl2 / 24 h / Ambient temperature 2: 1.) n-BuLi / 1.) hexane, THF, -70 deg C, 30 min, 2.) THF, -70 deg C, 90 min 3: 76 percent / AG-50WX4(resin) / methanol / 16 h / Ambient temperature View Scheme