in dichloromethane T=30°C; 3 h; Inert atmosphere;

1: in N,N-dimethyl acetamide T=20°C; 24 h; 2: in N,N-dimethyl acetamide; xylene T=140°C; 48 h;

water 1.) acetonitrile, room temperature, 5 min.; Multistep reaction;

1: perchloric acid; acetic anhydride / 2 h / 30 °C / |Inert atmosphere 2: triethylamine / diethyl ether / 0.5 h / |Inert atmosphere 3: cesium fluoride / acetonitrile / 2 h / 30 °C / |Inert atmosphere View Scheme