acetic acid in water; 1,2-dichloro-ethane T=80°C; Paal-Knorr reaction;

1: N,N-dimethyl-formamide With trichlorophosphate T=-10°C; 0.166667 h; 2: 1-(2-bromo-4-methyl-phenyl)-1H-pyrrole in 1,2-dichloro-ethane T=100°C; 3 h; Further stages.;