Hydrochloric Acid → Diethyl 2-(but-2-yn-1-yl)malonate

Participants

Reaction Steps

To a stirring mixture consisting of diethyl malonate (24.3 g, 141 mmol) in THF (140 mL) was added sodium hydride (60% dispersion in oil, 2.8 g, 70 mmol) and the resulting reaction mixture was stirred for 50 minutes. To the reaction mixture was added 1-bromobut-2-yne (GFS, 6.2 g, 47 mmol), and the mixture was stirred for two hours. The reaction mixture was treated carefully with 0.5 N HCl and extracted with ethyl acetate. The organic phase was washed with water, then brine, dried over magnesium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography. Elution with ethyl acetate-heptane (5:95 to 15:85 v/v) afforded the title intermediate (11.5 g, quantitative yield) as a clear oil.

Provenance & Evidence