N1C=CC=CC=1.FC(F)(F)C(OC(=O)C(F)(F)F)=O.[C:20]([C:24]1[CH:29]=[CH:28][C:27]([C:30](=O)[NH2:31])=[CH:26][C:25]=1[N+:33]([O-:35])=[O:34])([CH3:23])([CH3:22])[CH3:21].O>O1CCCC1.CCCCCC>[C:20]([C:24]1[CH:29]=[CH:28][C:27]([C:30]#[N:31])=[CH:26][C:25]=1[N+:33]([O-:35])=[O:34])([CH3:23])([CH3:21])[CH3:22]3.3 ml of pyridine and then 4.3 ml of trifluoroacetic anhydride were added to a solution of 2.25 g (10.1 mmol) of 2-t-butyl-5-carbamoyl-1-nitrobenzene [prepared as described in Preparation 38(i)] in 20 ml of tetrahydrofuran, and the resulting mixture was stirred for 20 minutes. The reaction mixture was then mixed with water, and the aqueous mixture was extracted with a mixture of ethyl acetate and hexane. The extract was washed with water and with a saturated aqueous solution of sodium chloride, after which it was dried over anhydrous sodium sulfate and the solvent was removed by distillation under reduced pressure. The residue was purified by column chromatography through 50 g of silica gel to give 1.99 g (yield 96%) of the title compound as crystals, melting at 70.5-71.5° C. (from hexane).
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