triethylamine; triphenylphosphine; palladium dichloride in 1,4-dioxane T=80°C; 4 h;

1: triethylamine / CHCl3 2: POCl3 / 0.5 h / 100 - 110 °C 3: 96.3 percent / 2N NaOH / ethanol / 0.25 h / 90 deg C bath View Scheme

1: triethylamine / CHCl3 2: POCl3 / 0.5 h / 100 - 110 °C 3: 96.3 percent / 2N NaOH / ethanol / 0.25 h / 90 deg C bath 4: SOCl2 / 1 h / Heating 5: NaBH4, 2N HCl / 1,2-dimethoxy-ethane / ice cooling 30 min, reflux 30 min View Scheme

1: triethylamine / CHCl3 2: POCl3 / 0.5 h / 100 - 110 °C 3: 96.3 percent / 2N NaOH / ethanol / 0.25 h / 90 deg C bath 4: SOCl2 / 1 h / Heating 5: NaBH4, 2N HCl / 1,2-dimethoxy-ethane / ice cooling 30 min, reflux 30 min 6: 99.7 percent / SOCl2 / 0.5 h / Ambient temperature View Scheme

1: triethylamine / CHCl3 2: POCl3 / 0.5 h / 100 - 110 °C 3: 96.3 percent / 2N NaOH / ethanol / 0.25 h / 90 deg C bath 4: SOCl2 / 1 h / Heating View Scheme

triethylamine; triphenylphosphine; palladium dichloride in 1,4-dioxane T=80°C; 4 h;