1: NaBH4 / ethanol / -20 - 0 °C 2: 73 percent / H2 / P-2 nickel View Scheme

1: 1) sodium hexamethyldisilazide / 1) THF, toluene, 2 h, 25 deg C, 2) THF, a) -100 deg C, 30 min, b) to 25 deg C, 3 h 2: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 3: tetrahydrofuran; hexamethylphosphoric acid triamide; toluene / -100 to 0 deg C, 3-4 h 4: 90 percent / Li, NH3, t-BuOH / tetrahydrofuran / 0.25 h / -40 °C View Scheme

1: 1) NaH / 1) DMF, a) 5 to 20 deg C, 1 h, b) 20 deg C, 30 min, 2) 5-15 deg C, 30 min 2: 99 percent / p-TsOH / tetrahydrofuran; H2O; propan-2-ol / 1 h / Heating 3: 1) sodium hexamethyldisilazide / 1) THF, toluene, 2 h, 25 deg C, 2) THF, a) -100 deg C, 30 min, b) to 25 deg C, 3 h 4: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 5: tetrahydrofuran; hexamethylphosphoric acid triamide; toluene / -100 to 0 deg C, 3-4 h 6: 90 percent / Li, NH3, t-BuOH / tetrahydrofuran / 0.25 h / -40 °C View Scheme

1: 99 percent / p-TsOH / tetrahydrofuran; H2O; propan-2-ol / 1 h / Heating 2: 1) sodium hexamethyldisilazide / 1) THF, toluene, 2 h, 25 deg C, 2) THF, a) -100 deg C, 30 min, b) to 25 deg C, 3 h 3: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 4: tetrahydrofuran; hexamethylphosphoric acid triamide; toluene / -100 to 0 deg C, 3-4 h 5: 90 percent / Li, NH3, t-BuOH / tetrahydrofuran / 0.25 h / -40 °C View Scheme

1: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 2: tetrahydrofuran; hexamethylphosphoric acid triamide; toluene / -100 to 0 deg C, 3-4 h 3: 90 percent / Li, NH3, t-BuOH / tetrahydrofuran / 0.25 h / -40 °C View Scheme

triphenylphosphine; diethylazodicarboxylate in toluene 0.5 h;