Nitric Acid → N-(4-chloro-2-fluoro-5-nitrophenyl)-3,4,5,6-tetrahydrophthalimide

A mixture of N-(4-chloro-2-fluorophenyl)-1-cyclohexene-1,2-dicarboximide (24.4 g, 86.7 mmol) in sulfuric acid (150 mL) is cooled to -3° C., treated dropwise with nitric acid (70% real, 6.70 mL, 104 mmol) while maintaining the temperature at 0°-2° C., stirred at room temperature for 90 minutes, and poured onto ice. The aqueous mixture is stirred for several minutes, and filtered to obtain a solid which is washed with water and dried to give the title product as a white powder (28.6 g, mp 152°-155° C.).