Hydrochloric Acid → (2E)-3-{4-[(3-Chloro-4-hydroxyphenyl)(3,3,5,5-tetramethylcyclohexylidene)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)(3,3,5,5-tetramethylcyclohexylidene)methyl]phenyl}-2-propenoate (128) (0.26 g, 0.57 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 and adding hexanes, the title compound 129 was obtained as light yellow foam (0.24 g, 99%). mp 111-114° C. 1H NMR (400 MHz, DMSO-d6): δ 0.86 (s, 6H), 0.88 (s, 6H), 1.25 (s, 2H), 1.87 (s, 2H), 1.90 (s, 2H), 6.45 (d, J=15.9 Hz, 1H), 6.80-6.95 (m, 2H), 7.06 (s, 1H), 7.16 (d, J=7.7 Hz, 2H), 7.53 (d, J=15.9 Hz, 1H), 7.59 (d, J=7.5 Hz, 2H), 10.08 (s, 1H), 12.33 (s, 1H). LCMS (ESI): m/z 423 (M−H)−. Anal. Calcd for C26H29ClO3: C, 73.48; H, 6.88; Found: C, 73.18; H, 7.06.

Provenance & Evidence