potassium carbonate in N,N-dimethyl-formamide T=80°C; 8 h;

1: 1.) phosphoryl chloride; 2.) K2CO3 / 1.) acetonitrile, 30-35 deg C, 3 h; 2.) acetone, reflux, 3 h; 2: 63 percent / K2CO3 / dimethylformamide / 0.67 h / 150 - 153 °C View Scheme

1.1: boron tribromide / dichloromethane / -78 - 20 °C 1.2: Cooling with ice 2.1: potassium carbonate / N,N-dimethyl-formamide / 8 h / 80 °C View Scheme

1: 3-chloro-benzenecarboperoxoic acid / dichloromethane / 4 h / 20 °C 2: sodium hydroxide / methanol / 3 h / 20 °C 3: potassium carbonate / N,N-dimethyl-formamide / 6 h / 80 °C View Scheme

1: 3-chloro-benzenecarboperoxoic acid / dichloromethane / 4 h / 20 °C 2: sodium hydroxide / methanol / 3 h / 20 °C 3: potassium carbonate / N,N-dimethyl-formamide / 6 h / 80 °C 4: trichlorophosphate / 3.5 h / 0 - 80 °C 5: potassium hydroxide / methanol; water / 24.5 h / 0 - 20 °C 6: palladium 10 on activated carbon; hydrogen / methanol; ethyl acetate / 72 h / 20 °C View Scheme

1: 3-chloro-benzenecarboperoxoic acid / dichloromethane / 4 h / 20 °C 2: sodium hydroxide / methanol / 3 h / 20 °C 3: potassium carbonate / N,N-dimethyl-formamide / 6 h / 80 °C 4: trichlorophosphate / 3.5 h / 0 - 80 °C View Scheme