1: triethylamine / dichloromethane; N,N-dimethyl-formamide / 1 h / 0 - 20 °C 2: 1,2-dichloro-ethane / 3 h / |Reflux View Scheme

1: triethylamine / CHCl3 2: POCl3 / 0.5 h / 100 - 110 °C 3: 98.4 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: 98.4 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: 90.7 percent / SOCl2 / 0.5 h / Ambient temperature View Scheme