3-(Trifluoromethyl)aniline → 3-Carboxy-1-(3-trifluoromethylphenyl)-2-pyrrolidinone

A mixture of 3-trifluoromethyl-phenylamine (2.8 g, 17.5 mmol) and 6,6-dimethyl-5,7-dioxa-spiro[2.5]octane-4,8-dione (1.0 g, 5.8 mmol) was stirred at 20-25° C. for 18 hrs. The reaction mixture was diluted with dichloromethane and washed with 10% NaOH solution (3×10 ml). The aqueous layer was cooled and acidified with dil HCl. The aqueous layer was extracted with dichloromethane, washed with saturated brine solution. The organic layer was dried over Na2SO4 and evaporated to obtain 2-oxo-1-(3-trifluoromethyl-phenyl)-pyrrolidine-3-carboxylic acid (1.1 g, 69%) as an off white solid.