1: 58.1 percent / p-toluenesulphonylhydrazide / acetic acid; CH2Cl2 / -17 deg C, 1 h; -1 to -2 deg C overnight and room temp., 2 h 2: 83 percent / L-Selectride / tetrahydrofuran / -78 deg C, 2 h, to room temp., 4 h 3: 39.1 percent / cuprous bromide, diisopropylamine / dioxane / 21 h / Heating 4: 57 percent / barium manganate / CH2Cl2 / 37 h / Ambient temperature View Scheme