C(OC(=O)C)(=O)C.[N+:8]([O-:11])(O)=[O:9].[CH3:12][O:13][C:14]1[CH:23]=[CH:22][C:21]2[C:16](=[CH:17][CH:18]=[CH:19][C:20]=2[CH3:24])[C:15]=1[C:25]([F:28])([F:27])[F:26]>O>[CH3:12][O:13][C:14]1[CH:23]=[CH:22][C:21]2[C:16](=[CH:17][CH:18]=[C:19]([N+:8]([O-:11])=[O:9])[C:20]=2[CH3:24])[C:15]=1[C:25]([F:26])([F:28])[F:27]To a cooled solution (3° to 4° C.) of acetic anhydride (640 mL) was added fuming nitric acid (90%, specific gravity=1.5, 160 mL) dropwise via an addition funnel at such a rate as to keep the internal temperature at or below 8° C. (~1 hour 20 minutes total addition time). After the internal temperature had again cooled to 3°-4° C., 2-methoxy-5-methyl-1-trifluoromethylnaphthalene (200 g, 0.833 mol) was added portion wise. The portions added were small enough such that the internal temperature did not rise above 10° C. and each portion was added when the temperature had cooled to 5° C. (addition time ~1 hour 15 minutes). After an additional 15 minutes the reaction mixture was added to water (3 L). The resulting amorphous solid was filtered, washed with water and the lumps broken up and dried in vacuo overnight. The dry solid (~225 g) was recrystallized from 95:5 ethanol:isopropanol (3 L). The resulting long yellow needles were filtered and washed with ethanol (2×50 mL) to provide the product (97.5 g, 41%), m.p. 141°-142° C. A small amount of the desired product was recrystallized from 4:1 petroleum ether:ethyl acetate.
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