4-Chlorobenzoic Acid → 3-{3-[3-t-Butyl-5-(4-chloro-benzoylamino)-pyrazol-1-yl]-phenyl}-propionic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

A solution of 4-chlorobenzoic acid (312 mg, 2.0 mmol) in SOCl2 (10 mL) was heated to reflux for 2 h. After removal of the solvent, the residue was dissolved into CH2Cl2 (5 mL) and was dropped into a solution of Example Z (315 mg, 1.0 mmol) in CH2Cl2 (10 mL) at 0° C., was then stirred at RT overnight. After quenching with water (50 mL), the reaction mixture was extracted with CH2Cl2 (3×100 mL). The combined organic extracts were washed with brine, dried (NaSO4) and filtered. After concentrated under reduced pressure, the residue was purified by flash chromatography to afford 3-{3-[3-t-butyl-5-(4-chloro-benzoylamino)-pyrazol-1-yl]-phenyl}-propionic acid ethyl ester (290 mg, 64%). 1H-NMR (CDCL3): 8.02 (s, 1H), 7.67 (d, J=8.4 Hz, 2H), 7.46 (t, J=7.6 Hz, 1H), 7.44 (d, J=8.4 Hz, 2H), 7.36 (t, J=8.4 Hz, 3H), 6.87 (s, 1H), 4.06 (q, J=7.6 Hz, 2H), 3.02 (t, J=7.6 Hz, 2H), 2.67 (t, J=7.6 Hz, 2H), 1.40 (s, 9H), 1.12 (t, J=7.6 Hz, 3H); MS (ESI) m/z: 454 (M+H+).

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