Ethyl 4-methoxyphenylacetate → Ethyl 3-(4-cyano-2-methylphenyl)-2-(4-methoxyphenyl)-3-oxopropanoate

Beteiligte Stoffe

Reaktionsschritte

To a solution of (4-methoxy-phenyl)-acetic acid ethyl ester (25.96 g, 133.7 mmol) in anhydrous tetrahydrofuran (200 mL) was added lithium hexamethyldisilazide (200 mL, 1 M) at −78° C. under nitrogen. After being stirred for 15 min., a solution of A-5 (4-cyano-2-methylbenzoyl chloride) (24 g, 133.6 mmol) in anhydrous tetrahydrofuran (150 mL) was added dropwise, and the resulting mixture was stirred at room temperature overnight for 16 h. The reaction mixture was quenched by the addition of saturated aqueous ammonium chloride solution (200 mL), and the resultant mixture was extracted with ethyl acetate (100 mL×3). The combined organic layers were dried over anhydrous sodium sulfate (20 g), filtered, and evaporated. The residue was purified on silica gel column (petroleum ether/ethyl acetate=25:1) to give A-6 (ethyl 3-(4-cyano-2-methylphenyl)-2-(4-methoxyphenyl)-3-oxopropanoate) (40 g, yield 88.7%).

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