Triethylamine → 1,1-Dimethylethyl (2E)-3-{4-[cyclopentylidene(4-hydroxyphenyl)methyl]phenyl}-2-propenoate

Participants

Reaction Conditions

Reaction Steps

4-[(4-Bromophenyl)(cyclopentylidene)methyl]phenol (3) (0.351 g, 1.07 mmol), tert-butyl acrylate (0.94 mL, 0.82 g, 6.4 mmol, 6 eq), Pd(OAc)2 (0.051 g, 0.23 mmol, 0.21 eq), Et3N (0.89 mL, 0.65 g, 6.4 mmol, 6 eq), P(o-tolyl)3 (0.139 g, 0.46 mmol, 0.43 eq), and anhydrous CH3CN (16 mL) were combined in a round-bottomed flask and the reaction mixture was heated overnight at 85° C., with stirring, under a nitrogen atmosphere. The reaction mixture was allowed to cool to room temperature and transferred to a separatory funnel with the aid of EtOAc and water. The layers were separated and the organic phase washed with brine, dried over MgSO4, filtered, and the filtrate was concentrated to give the crude product. The crude product was purified by flash chromatography on silica gel with hexanes:EtOAc (100:0 to 50:50) to give 0.30 g (74%) of compound 4 as a pale yellow solid. 1H NMR (400 MHz, DMSO-d6) δ 1.45 (s, 9 H), 1.60 (m, 4 H), 2.30 (m, 4 H), 6.43 (d, J=15.9 Hz, 1 H), 6.67 (d, J=8.6 Hz, 2 H), 6.90 (d, J=8.4 Hz, 2 H), 7.12 (d, J=8.2 Hz, 2 H), 7.49 (d, J=15.9 Hz, 1 H), 7.58 (d, J=8.3 Hz, 2 H), 9.32 (s, 1 H). HRMS (EI) Calcd for C25H28O3: 376.2038 (M+). Found: 376.2046.

Provenance & Evidence