1: 52 percent / triethylamine / CH2Cl2 / 0.25 h / 0 - 10 °C 2: 1.) sodium hydride / dimethylformamide / 1.) 40 min, room temperature, 2.) 100 deg C, 18 h View Scheme

sodium hydride in N,N-dimethyl-formamide 1.) 40 min, room temperature, 2.) 100 deg C, 18 h;