反应详情

温度

45 °C

Cone. H2SO4 (0.5 mL) was added to a solution of 2-(5-amino-1-phenyl-1 H-pyrazol-3-yl)-2-methylpropanoic acid (0.7 g, 28.5 mmol) in EtOH (10 mL) and the reaction was heated at 45° C. for 2 h. The reaction solution was neutralized with aq NaHCO3 and then extracted with EtOAc (3×20 mL). The combined extracts were washed with aq NaHCO3 solution, dried (Na2SO4), and concentrated in vacuo to give ethyl 2-(5-amino-1-phenyl-1 H-pyrazol-3-yl)-2-methylpropanoate (710 mg, 91% yield). 1H NMR (400 MHz, DMSO-d6): δ 7.62 (d, δ 7.6 Hz, 2 H), 7.52 (t, J=7.6 Hz, 2 H), 7.35 (t, J=7.6 Hz, 1 H), 5.47 (s, 1 H), 5.35 (br s, 2 H), 4.12 (q, J= 7.2 Hz, 2 H), 1.50 (s, 6 H), 1.22 (t, J=7.2 Hz, 3 H); MS (ESI) m/z: 274.1(M+H+).

1. extractionextracted with EtOAc (3×20 mL)
2. washThe combined extracts were washed with aq NaHCO3 solution
3. dry with materialdried (Na2SO4)
4. concentrationconcentrated in vacuo