1: With sodium carbonate in water; acetone T=20°C; 18 h; 2: With potassium hydrogensulfate in water pH=2;

dipyridinium dichromate in N,N-dimethyl-formamide T=25°C; 6 h;

1: Et3N, DMAP / CH2Cl2 / 9 h / Ambient temperature 2: 80 percent / NaBH4, MeOH / ethanol / 24 h / Ambient temperature 3: pyridinium dichromate / dimethylformamide / 6 h / Ambient temperature View Scheme

1: Et3N, DMAP / CH2Cl2 / 9 h / Ambient temperature 2: 80 percent / NaBH4, MeOH / ethanol / 24 h / Ambient temperature 3: pyridinium dichromate / dimethylformamide / 6 h / Ambient temperature View Scheme

1: PyH*OTs / CH2Cl2 / 24 h / 25 °C 2: NaBH4 / methanol / 1 h / 25 °C 3: 97 percent / pyridine 4: 88 percent / dimethylformamide / 1 h / 0 °C 5: 90 percent / mCPBA 6: PyH*OTs / ethanol / 6 h / 60 °C 7: 95 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 8: 96 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 9: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 10: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 11: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 95 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 2: 96 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 3: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 4: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 5: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 2: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 3: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 97 percent / pyridine 2: 88 percent / dimethylformamide / 1 h / 0 °C 3: 90 percent / mCPBA 4: PyH*OTs / ethanol / 6 h / 60 °C 5: 95 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 6: 96 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 7: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 8: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 9: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: NaBH4 / methanol / 1 h / 25 °C 2: 97 percent / pyridine 3: 88 percent / dimethylformamide / 1 h / 0 °C 4: 90 percent / mCPBA 5: PyH*OTs / ethanol / 6 h / 60 °C 6: 95 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 7: 96 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 8: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 9: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 10: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 90 percent / mCPBA 2: PyH*OTs / ethanol / 6 h / 60 °C 3: 95 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 4: 96 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 5: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 6: 6 percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 7: pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme