1: 70 percent / Dowex 50W-X8 / H2O / 36 h / 25 °C 2: HOAc, NaBH3CN / methanol / 1.) -78 deg C, 2 h, 2.) r.t., 20 h 3: 99 percent / H2 / 20percent Pd(OH)2/C / methanol / 24 h / 3102.9 Torr View Scheme

tetra-N-butylammonium borohydride in dichloromethane T=0°C; 0.5 h;

1: 70 percent / Dowex 50W-X8 / H2O / 36 h / 25 °C 2: 55 percent / HOAc, NaBH3CN / methanol / 1.) -78 deg C, 2 h, 2.) r.t., 20 h View Scheme

lithium aluminium tetrahydride

1: pyridine 2: 1.) TsNHNH2, 2.) NaBH4 / 1.) MeOH, 2.) MeOH, heating 3: CrO3 / pyridine; acetic anhydride 4: NaBH4 / ethanol 5: TBAF / tetrahydrofuran View Scheme