4-(N,N-dimethlyamino)pyridine in chloroform 20 h; Ambient temperature;

1: 75 percent / CH3ONa / methanol 2: 1.) triethylamine / 1.) in benzene; 2.) in acetonitrile, 65 deg C, 16 h 3: CF3COOH / CHCl3 / 1 h / Ambient temperature 4: 62 percent / DMAP / CHCl3 / 20 h / Ambient temperature View Scheme

1: 1.) triethylamine / 1.) in benzene; 2.) in acetonitrile, 65 deg C, 16 h 2: CF3COOH / CHCl3 / 1 h / Ambient temperature 3: 62 percent / DMAP / CHCl3 / 20 h / Ambient temperature View Scheme

1: CF3COOH / CHCl3 / 1 h / Ambient temperature 2: 62 percent / DMAP / CHCl3 / 20 h / Ambient temperature View Scheme