Acetic Acid → 1-(4-Tert-butyl-2-nitrophenyl)-2,5-dimethylpyrrole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stifling solution of 2-nitro-4-tert-butylaniline (0.5 g, 2.57 mmol) in cyclohexane (10 mL) was added AcOH (0.1 mL) and acetonylacetone (0.299 g, 2.63 mmol) via syringe. The reaction mixture was heated at 120° C. for 72 h with azeotropic removal of volatiles. The reaction mixture was cooled to room temp., diluted with CH2Cl2 (10 mL) and sequentially washed with a 1N HCl solution (15 mL), a 1N NaOH solution (15 mL) and a saturated NaCl solution (15 mL), dried (MgSO4) and concentrated under reduced pressure. The resulting orange-brown solids were purified via column chromatography (60 g SiO2; gradient from 6% EtOAc/94% hexane to 25% EtOAc/75% hexane) to give 1-(4-tert-butyl-2-nitrophenyl)-2,5-dimethylpyrrole as an orange-yellow solid (0.34 g, 49%): TLC (15% EtOAc/85% hexane) Rf 0.67; 1H NMR (CDCl3) d 1.34 (s, 9H), 1.89 (s, 6H), 5.84 (s, 2H), 7.19-7.24 (m, 1H), 7.62 (dd, 1H), 7.88 (d, J=2.4 Hz, 1H); CI-MS m/z 273 ((M+H)+, 50%).

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