in N,N-dimethyl-formamide T=20°C; 5 h;

1: (2R)-2-ethoxycarbonyl-2-(pyrrol-1-yl)succinimide diisopropylamine salt With sulfuric acid; water in ethyl acetate 2: With 2,2,2-trichloroacetyl chloride in ethyl acetate 6 h; Heating / reflux; 3: 4-bromo-2-fluorobenzylamine With water; sodium hydrogencarbonate; diisopropylamine more than 3 stages;

triethylamine in N,N-dimethyl-formamide 16 h; Ambient temperature;