A solution of 1,1-dimethylethyl (2E)-3-{4-[cyclohexylidene(4-hydroxyphenyl)methyl]phenyl}-2-propenoate (7) (0.24 g, 0.61 mmol) in CH2Cl2 (6 mL) was cooled in an ice-water bath and stirred under a nitrogen atmosphere. To the cold solution was slowly added trifluoroacetic acid (6 mL). The reaction mixture was stirred in the ice-water bath under a nitrogen atmosphere for 1 h. The reaction mixture was concentrated to give the crude product as a solid. The crude product was dissolved in CH2Cl2 and the solution was concentrated to give a solid. The crude product was transferred to a separatory funnel with the aid of CH2Cl2 and H2O. The organic phase was removed and the aqueous phase that contained suspended solids was extracted twice with CH2Cl2. The organic phase was removed and the aqueous suspension was filtered with the aid of H2O. The filtered white solid was dissolved in CH2Cl2 and MeOH and the solution was filtered. The filtrate was concentrated and the resulting solid was dried in a vacuum oven to give 135 mg (67%) of compound 8 as an off-white solid. 1H NMR (400 MHz, DMSO-d6): δ 1.52 (m, 6H), 2.15 (m, 4H), 6.44 (d, J=15.9 Hz, 1H), 6.66 (d, J=8.4 Hz, 2H), 6.84 (d, J=8.4 Hz, 2H), 7.05 (d, J=8.0 Hz, 2H), 7.52 (d, J=15.9 Hz, 1H), 7.57 (d, J=8.0 Hz, 2H), 9.31 (s, 1H), 12.31 (br s, 1H). The sample was silated prior to EI analysis. HRMS (EI) Calcd for C28H38O3Si2: 478.2360 (M+). Found: 478.2376.
