N-[[6-Methoxy-2-(2,2,2-trifluoroethoxy)-5-(trifluoromethyl)-1-naphthalenyl]carbonyl]-N-(methoxycarbonyl)glycine, 1,1-Dimethylethyl Ester → 2-[N-Methoxycarbonyl-N-[[2-(2,2,2-trifluoroethoxy)-6-methoxy-5-trifluoromethyl-1-naphthalenyl]carbonyl]amino]acetic acid

A suspension of N-[[6-methoxy-2-(2,2,2-trifluoroethoxy)-5-(trifluoromethyl)-1-naphthalenyl]carbonyl]-N-(methoxycarbonyl)glycine, 1,1-dimethylethyl ester (5.86 g, 10.9 mmol) in formic acid (135 mL) was stirred at room temperature under a dry nitrogen atmosphere. After 10 minutes, dissolution occurred. After 1 hour, the reaction mixture was diluted with water (1.5 L) and extracted with ether (2×400 mL). The extracts were combined and the ether was removed. The residue was suspended in water (100 mL) and filtered. The solid was washed with water (2×20 mL) and air dried. The crude product was recrystallized from chloroform to provide the title compound as a white powder (4.15 g, 79%), m.p. 186°-187° C.