1: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -60 deg C, 3.5 h, 2.) MeOH, 30 deg C, 10 min 2: 95 percent / 85percent H3PO4 / 0.08 h / 50 °C 3: 94 percent / 85percent KOH / ethanol / 2 h / Heating 4: SOCl2, DMF / Ambient temperature View Scheme

1: 94 percent / 85percent KOH / ethanol / 2 h / Heating 2: SOCl2, DMF / Ambient temperature View Scheme

thionyl chloride; N,N-dimethyl-formamide Ambient temperature;