Diethyl Malonate → 1,1-Diethyl cyclopent-3-ene-1,1-dicarboxylate

Participants

Reaction Steps

To an ice-cooled solution of diethyl malonate (75.01 g, 468.3 mmol) in tetrahydrofuran (1.5 L) was added sodium hydride (28.1 g, 1.17 mmol) portionwise. After 1 h, (Z)-1,4-dichlorobut-2-ene (75.0 g, 468 mmol) in tetrahydrofuran (500 mL) was added over 40 min at 0° C. After 1 h, the reaction mixture was diluted with saturated aqueous ammonia chloride solution (500 mL), and the resulting mixture was extracted with ethyl acetate (2×2 L). The collected organic was dried over anhydrous sodium sulfate, filtered, and concentrated. Purification by flash column chromatography (petroleum ether) provided product as a yellow oil (85 g, 86% yield).

Provenance & Evidence