The procedure of Example 1 is repeated using 3.9 g (25 mmol) of 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine, 7.84 g (76 mmol) of tert-butyl nitrite, 25 mg (0.25 mmol) of copper(II) fluoride, 120 mL of acetonitrile and 10.3 g (50 mmol) of 2-nitro-4-trifluoromethylaniline at 65° C. The crude product obtained is purified by vacuum flash chromatography (heptane) to give 6.0 g of light yellow crystals melting at 54-55° C., a 68.9% yield based on nitroxyl. The structure is confirmed by 1Hnmr, mass spectroscopy and elemental analyses.
