Hydrochloric Acid → (2E)-3-{4-[(3-Chloro-4-hydroxyphenyl)(cycloheptylidene)methyl]phenyl}-2-propenoic acid

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Reaction Conditions

Reaction Steps

To a solution of ethyl (2E)-3-{4-[(3-chloro-4-hydroxyphenyl)(cycloheptylidene)methyl]phenyl}-2-propenoate (125) (0.23 g, 0.56 mmol) in a mixture of EtOH (6 mL) and THF (6 mL) was added an aqueous solution of 1 N NaOH (7 mL). The mixture was stirred at 60° C. for 2 h. Upon cooling, the mixture was acidified to pH=2 with an aqueous solution of 2 N HCl. The mixture was extracted with EtOAc (2×50 mL). The combined organic extract was washed with brine and dried over Na2SO4. Upon concentration, light brown foam was obtained. Trituration with hexanes (containing 1% MeOH) afforded compound 126 as a white solid (0.175 g, 82%). mp 155-156° C. 1H NMR (400 MHz, DMSO-d6): δ 1.51 (br s, 8H), 2.10-2.30 (m, 4H), 6.45 (d, J=15.9 Hz, 1H), 6.80-6.95 (m, 2H), 7.02 (s, 1H), 7.14 (d, J=7.8 Hz, 2H), 7.52 (d, J=16.1 Hz, 1H), 7.58 (d, J=7.8 Hz, 2H), 10.08 (s, 1H), 12.33 (s, 1H). LCMS (ESI): m/z 383 (M+H)+, m/z 381 (M−H)−. Anal. Calcd for C23H23ClO3.0.25H2O: C, 71.31; H, 6.11; Found: C, 71.26; H, 6.05.

Provenance & Evidence