1: dimethylformamide / 1 h / 0 °C 2: 92 percent / NaBH4 / methanol / 1 h / 25 °C 3: 93 percent / mCPBA / CH2Cl2 / 1 h / 25 °C 4: 95 percent / PyH*OTs / CH2Cl2 / 24 h / 25 °C 5: 1.) n-BuLi / 1.) THF, -78 deg C; 2.) -50 deg C, 2 h 6: 93 percent / PyH*OTs / ethanol / 6 h / 60 °C 7: 92 percent / 6percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 8: 78 percent / 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: 93 percent / PyH*OTs / ethanol / 6 h / 60 °C 3: 92 percent / 6percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 4: 78 percent / pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 92 percent / 6percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 2: 78 percent / pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

1: 93 percent / PyH*OTs / ethanol / 6 h / 60 °C 2: 92 percent / 6percent Na-Hg, Na2HPO4 / methanol / 24 h / 25 °C 3: 78 percent / pyridinium dichromate / dimethylformamide / 6 h / 25 °C View Scheme

Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;

trifluoroacetic acid in dichloromethane T=20°C; 3 h;

urea; trifluoroacetic acid; sodium nitrite in dichloromethane; sulfuric acid; water