thionyl chloride; N,N-dimethyl-formamide in chloroform 1.5 h; Heating;

1: POCl3, N,N-dimethylaniline 2: K2CO3 / dimethylsulfoxide View Scheme

1: 58 percent / thionyl chloride, DMF / CHCl3 / 1.5 h / Heating 2: 83 percent / ethanol / 66 h 3: 72 percent / K2CO3 / dimethylformamide / 48 h / Ambient temperature View Scheme