1: 2,4,6-trifluorobenzoyl chloride With AlCl3, aluminium chloride in dichloromethane T=20°C; 0.25 h; Inert atmosphere; 2: pyrrole-2-carboxylic acid ester in dichloromethane T=20°C; 1.16667 h; 3: With hydrogenchloride; water in dichloromethane pH=1;