Hydrochloric Acid → 4'-[(4-Hydroxyphenyl)(3,3,5,5-tetramethylcyclohexylidene)methyl]-2-biphenylcarboxylic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of methyl 4′-[(4-hydroxyphenyl)(3,3,5,5-tetramethylcyclohexylidene)methyl]-2-biphenylcarboxylate (248) (0.108 g, 0.24 mmol) in a mixture of EtOH (6 mL) and THF (4 mL) was added an aqueous solution of 1N NaOH (10 mL). The mixture was stirred at 60° C. overnight. 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 (249) as white solid (92.8 mg, 89%). mp 230-231° C. 1H NMR (400 MHz, DMSO-d6): δ 0.88 (s, 6H), 0.89 (s, 6H), 1.25 (s, 2H), 1.91 (s, 4H), 6.67 (d, J=8.4 Hz, 2H), 6.95 (d, J=8.2 Hz, 2H), 7.14 (d, J=8.0 Hz, 2H), 7.23 (d, J=8.0 Hz, 2H), 7.34-7.44 (m, 2H), 7.50-7.55 (m, 1H), 7.65 (d, J=7.7 Hz, 1H), 9.27 (s, 1H), 12.72 (s, 1H). LCMS (ESI): m/z 441 (M+H)+, 439 (M−H)−.

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