Nitric Acid → 4-bromo-nitroisophthalic Acid

Beteiligte Stoffe

Reaktionsschritte

To a 3-L 4-neck round-bottomed flask equipped with a mechanical stirrer, thermometer, 250-mL addition funnel and charged with concentrated H2SO4 (577 mL), was added 4-bromoisophthalic acid (75.0 g, 306 mmol). The white suspension was cooled to ice-bath temperature and a nitrating reagent (pre-prepared by the careful addition of H2SO4 (169 mL) to HNO3 (107 mL)) was slowly added while maintaining an internal reaction temperature of less than 15° C. When addition was complete, the ice-bath was removed and the suspension stirred overnight at room temperature. After approximately 14 hours, the flask was placed in an ice-bath and crushed ice was added to quench the excess nitrating reagent while maintaining an internal temperature less than 40° C. The cream-colored suspension was filtered, and the solids were collected by filtration and washed with a small volume of ice-cold water. The solids were dissolved in methanol and the volatile components were evaporated. The resulting solids were dried at 60° C. in a vacuum oven overnight to afford Intermediate 39(a) (79.6 g) in 87% yield.

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