4-(N,N-dimethlyamino)pyridine; triethylamine in N,N-dimethyl-formamide T=20°C; 18 h; Inert atmosphere;

N-ethyl-N,N-diisopropylamine in N,N-dimethyl-formamide T=20°C; 3.08333 h;

1: boron trichloride / dichloromethane / 20 h / 20 °C / Inert atmosphere 2: 4-(N,N-dimethlyamino)pyridine; triethylamine / N,N-dimethyl-formamide / 18 h / 20 °C / Inert atmosphere View Scheme