反应详情

To a solution of 4-(2′,4′-dichloro-4-ethylbiphen-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione (0.200 g, 0.478 mmol) in glacial acetic acid (5 ml) is added sodium nitrite (0.0025 g, 0.036 mmol) then fuming nitric acid (0.12 ml). The mixture is stirred at room temperature for 2 hours, then the resulting slurry is poured into ice-water (50 ml). After swirling for 5 minutes the precipitate is filtered, dried, then washed with hexanes to afford 4-(2′,4′-dichloro-4-ethyl-biphen-3-yl)-2,2,6,6-tetramethyl-4-nitropyran-3,5-dione (0.201 g, 91%) as a yellow solid, m.p.=138-140° C.

1. waitAfter swirling for 5 minutes
2. filtrationthe precipitate is filtered
3. customdried
4. washwashed with hexanes