[N+:1]([O-:4])([O-])=[O:2].[K+].[CH3:6][O:7][C:8]1[C:13]2[CH2:14][CH2:15][CH2:16][C:17](=[O:19])[CH2:18][C:12]=2[CH:11]=[CH:10][CH:9]=1>C(#N)C.FC(F)(F)C(OC(=O)C(F)(F)F)=O>[CH3:6][O:7][C:8]1[C:13]2[CH2:14][CH2:15][CH2:16][C:17](=[O:19])[CH2:18][C:12]=2[CH:11]=[CH:10][C:9]=1[N+:1]([O-:4])=[O:2]To potassium nitrate in acetonitrile (50 mL) and trifluoroacetic anhydride (100 mL) at 0° C. was added dropwise 1-methoxy-5,7,8,9-tetrahydro-benzocyclohepten-6-one (25 g, 0.131 mol) in 50 mL acetonitrile. The reaction was stirred for 2.5 hours while warming to RT. The reaction was concentrated without heat on a rotary evaporator. MeOH was added and stirred briefly. Reconcentrated and worked-up by partitioning between dichloromethane and sat. sq. sodium bicarbonate solution. The organic layer was separated and dried (Mg2SO4), concentrated and purified by chromatography ISCO (330 g silica cartridge: gradient elution—10 to 50% EA:HEX over 60 minutes) affording two isomers. The title compound was the later eluting (10.7 grams, 34.6% yield). 1H-NMR (400 MHz, CDCl3) 7.70 (d, J=8.3 Hz, 1H), 7.06 (d, J=8.3 Hz, 1H), 3.92 (s, 3H), 3.80 (s, 2H), 3.13-3.09 (m, 2H), 2.60 (t, J=7.0 Hz, 2H), 2.10-2.03 (m, 2H).
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