Hydrochloric Acid → 5-{4-[(4-Hydroxyphenyl)(3,3,5,5-tetramethylcyclohexylidene)methyl]phenyl}-4-pentynoic acid

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Reaction Conditions

Reaction Steps

To a solution of methyl 5-{4-[(4-hydroxyphenyl)(3,3,5,5-tetramethylcyclohexylidene)methyl]phenyl}-4-pentynoate (243) (0.16 g, 0.38 mmol) in a mixture of EtOH (5 mL) and THF (5 mL) was added an aqueous solution of 1N NaOH (6 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 1 N HCl. The mixture was extracted with EtOAc (2×50 mL). The combined organic extract was washed with brine and dried over Na2SO4. Concentration gave a white residue, which was triturated with hot hexanes containing 1% MeOH to yield the title compound (244) as white solid (0.15 g, 95%), mp 233-234° C. 1H NMR (400 MHz, CH3OH-d6): δ 0.91 (s, 6H), 0.92 (s, 6H), 1.29 (s, 2H), 1.94 (s, 2H), 1.98 (s, 2H), 2.50-2.60 (m, 2H), 2.60-2.70 (m, 2H), 6.68 (d, J=8.6 Hz, 2H), 6.94 (d, J=8.6 Hz, 2H), 7.07 (d, J=8.3 Hz, 2H), 7.25 (d, J=8.1 Hz, 2H). LCMS (ESI): m/z 417 (M+H)+, 415 (M−H)−.

Provenance & Evidence