1: 19 percent / pyridine, 4-(dimethylamino)pyridine / 16 h / Ambient temperature 2: 13 percent / 1 M NaOH / ethanol / 0.25 h / Ambient temperature 3: 96 percent / acetonitrile / 20 h / Heating 4: NaBH4 / methanol / 1 h / -10 °C 5: HgCl2 / acetonitrile; H2O / 0.25 h 6: NaCNBH3, 1 M HCl, 3-Angstroem molecular sieves / methanol / 112 h / Ambient temperature View Scheme

1: 19 percent / pyridine, 4-(dimethylamino)pyridine / 16 h / Ambient temperature 2: 13 percent / 1 M NaOH / ethanol / 0.25 h / Ambient temperature 3: 96 percent / acetonitrile / 20 h / Heating 4: NaBH4 / methanol / 1 h / -10 °C 5: HgCl2 / acetonitrile; H2O / 0.25 h 6: NaCNBH3, 1 M HCl, 3-Angstroem molecular sieves / methanol / 112 h / Ambient temperature 7: 86 percent / trifluoroacetic acid / 1 h / Ambient temperature View Scheme

1: 19 percent / pyridine, 4-(dimethylamino)pyridine / 16 h / Ambient temperature 2: 13 percent / 1 M NaOH / ethanol / 0.25 h / Ambient temperature 3: 96 percent / acetonitrile / 20 h / Heating 4: NaBH4 / methanol / 1 h / -10 °C 5: HgCl2 / acetonitrile; H2O / 0.25 h 6: NaCNBH3, 1 M HCl, 3-Angstroem molecular sieves / methanol / 112 h / Ambient temperature 7: 86 percent / trifluoroacetic acid / 1 h / Ambient temperature 8: 48 percent / 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 64 h / Ambient temperature 9: H2 / 10percent Pd/C / ethanol / 16 h 10: 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 16 h / Ambient temperature View Scheme

1: 19 percent / pyridine, 4-(dimethylamino)pyridine / 16 h / Ambient temperature 2: 13 percent / 1 M NaOH / ethanol / 0.25 h / Ambient temperature 3: 96 percent / acetonitrile / 20 h / Heating 4: NaBH4 / methanol / 1 h / -10 °C 5: HgCl2 / acetonitrile; H2O / 0.25 h 6: NaCNBH3, 1 M HCl, 3-Angstroem molecular sieves / methanol / 112 h / Ambient temperature 7: 86 percent / trifluoroacetic acid / 1 h / Ambient temperature 8: 48 percent / 1-hydroxybenzotriazole hydrate, dicyclohexylcarbodiimide, N-ethylmorpholine / tetrahydrofuran / 64 h / Ambient temperature View Scheme