pyridine; phosgene in chloroform; toluene 1.) 25 deg C, 30 min, 2.) 50 deg C, 2 h;

1: 74 percent / hydrogen chloride / CHCl3 / Heating 2: 22 percent / pyridine, phosgene / CHCl3; toluene / 1.) 25 deg C, 30 min, 2.) 50 deg C, 2 h View Scheme

in benzene 35 h; Irradiation;