Triethylamine → 3-(5-amino-4-benzoyl-1H-pyrazol-1-yl)-4-methylbenzoic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 3-hydrazino-4-methyl-benzoic acid hydrochloride 2 (242 mg, 1.19 mmol, 1.0 eq) in 25 mL of ethanol was added 2-benzoyl-3-phenylamino-acrylonitrile 4 (296 mg, 1.19 mmol, 1.0 eq, preparation: Grothasu, Davis, J. Am. Chem. Soc., 58, 1334 (1936)) and triethylamine (161 μL, 1.19 mmol, 1.0 eq) and the mixture was heated to 65° C. All solids dissolved when temperature reached 65° C. After three hours, LC-MS indicates consumption of the hydrazine. The solids were filtered to provide 3-(5-amino-4-benzoyl-pyrazol-1-yl)-4-methyl-benzoic acid 5 (95 mg, 25%) as a beige solid: HPLC (4 minute gradient) tR 2.10 min; MS m/z 322 [M+H]+; 1H NMR (DMSO-d6, 300 MHz) δ 7.99 (d, J=7.6, 1 H), 7.81 (s, 2 H), 7.78 (s, 1 H), 7.57 (m, 4 H), 7.02 (s, 2 H, NH2, 2.18 (s, 3 H) ppm; 13C NMR (DMSO-d6, 75 MHz) 187.6, 166.3, 152.0, 141.3, 141.2, 139.6, 135.9, 131.6, 131.2, 130.1, 129.8, 128.6, 127.8, 102.6, 17.4 ppm.

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