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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a round-bottomed flask were added 4-[(4-bromophenyl)(cyclohexylidene)methyl]phenol (6) (0.465 g, 1.35 mmol), tert-butyl acrylate (0.58 mL, 0.508 g, 3.96 mmol, 2.9 eq), Pd(OAc)2 (0.03 g, 0.134 mmol, 0.1 eq), triethylamine (0.54 mL, 0.39 g, 3.87 mmol, 2.9 eq), P(o-tolyl)3 (0.08 g, 0.26 mmol, 0.19 eq), and CH3CN (6 mL). The reaction mixture was heated overnight at 75° C. with stirring under a nitrogen atmosphere. Thin layer chromatography indicated the reaction was not complete. To the reaction mixture were added P(o-tolyl)3 (0.087 g, 0.29 mmol, 0.21 eq), tert-butyl acrylate (0.58 mL, 0.51 g, 3.96 mmol, 2.9 eq), paladium II acetate (0.033 g, 0.147 mmol), triethylamine (0.54 mL, 0.39 g, 3.87 mmol), and CH3CN (2 mL). The reaction mixture was heated at 75° C. with stirring under a nitrogen atmosphere for three days. The reaction mixture was allowed to cool to room temperature and transferred to a separatory funnel with the aid of EtOAc and H2O. The layers were separated and the organic phase was washed with brine. The organic solution was dried over MgSO4, filtered, and the filtrate was concentrated to give the crude product as an oil. The crude product was purified by flash chromatography on silica gel with hexanes:EtOAc (100:0 to 50:50) to give 0.40 g (76%) of compound 7 as a pale yellow solid. 1H NMR (400 MHz, DMSO-d6): δ 1.45 (s, 9H), 1.52 (m, 6H), 2.14 (m, 4H), 6.43 (d, J=15.9 Hz, 1H), 6.66 (d, J=8.5 Hz, 2H), 6.84 (d, J=8.4 Hz, 2H), 7.05 (d, J=8.1 Hz, 2H), 7.48 (d, J=15.9 Hz, 1H), 7.57 (d, J=8.1 Hz, 2H), 9.31 (s, 1H). The sample was silated prior to EI analysis. HRMS (EI) Calcd for C29H38O3Si: 462.2590 (M+.). Found: 462.2592.

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