2-Chloro-4-hydrazinylbenzonitrile hydrochloride → 2-(3-Chloro-4-cyanophenyl)-3-cyclopropyl-2,3,3a,4-tetrahydrochromeno[4,3-c]pyrazole-7-carboxylic acid

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The title compound was prepared from methyl 3-(cyclopropylmethylene)-4-oxochroman-7-carboxylate; Preparation 33 and 2-chloro-4-hydrazinylbenzonitrile hydrochloride; Preparation 1 according to Method B and Method C. The crude product was purified by reverse-phase HPLC (65 to 85% acetonitrile/water/0.05% trifluoroacetic acid) to give 2-(3-chloro-4-cyanophenyl)-3-cyclopropyl-2,3,3a,4-tetrahydrochromeno[4,3-c]pyrazole-7-carboxylic acid (yellow solid, 14 mg). The title compound was largely present as (±)-(3RS,3aSR)-2-(3-chloro-4-cyanophenyl)-3-cyclopropyl-2,3,3a,4-tetrahydrochromeno[4,3-c]pyrazole-7-carboxylic acid. 1H NMR (400 MHz, DMSO-d6) δ ppm 13.18 (br. s., 1H), 7.97 (d, J=8.2 Hz, 1H), 7.73 (d, J=9.0 Hz, 1H), 7.59 (dd, J=8.2, 1.6 Hz, 1H), 7.48 (d, J=1.6 Hz, 1H), 7.43 (d, J=2.0 Hz, 1H), 7.23 (dd, J=8.6, 1.6 Hz, 1H), 4.84 (dd, J=10.5, 5.9 Hz, 1H), 4.46 (dd, J=12.9, 10.5 Hz, 1H), 4.39 (t, J=10.0 Hz, 1H), 3.93 (ddd, J=13.1, 10.2, 5.7 Hz, 1H), 0.74-0.85 (m, 1H), 0.63-0.71 (m, 1H), 0.52-0.61 (m, 1H), 0.37-0.45 (m, 1H), 0.18-0.26 (m, 1H).

Provenance & Evidence