thionyl chloride; N,N-dimethyl-formamide in dichloromethane; benzene 0.5 h; Ambient temperature;

pyridine; tetrachloromethane; triphenylphosphine 1.) DMF, 10 min, 2.) DMF, RT, 1.5 h; Yield given. Multistep reaction;

1: 1.) trimethylchlorosilane, hexamethyldisilazane, 2.) trimethylsilyl triflate / 1.) reflux, 3 h, 2.) CHCl3, RT, 1 h 2: 83 percent / 1N NaOEt / ethanol / Ambient temperature View Scheme