Diethyl Malonate → Diethyl (3-methylbut-2-enyl)malonate

Participants

Reaction Steps

422 mg (14.1 mmol, 80% mineral oil dispersion) sodium hydride was washed 3 ×, each with 5 mL pentane, and suspended in a mixture of 10 mL tetrahydrofuran and 5 mL dimethylformamide. 2.04 g (13.4 mmol) diethyl malonate was added, and the mixture stirred for 40 mins to form a clear light brown solution. Prenyl bromide (2.00 g, 13.4 mmol) was then added, and the solution refluxed for 1 hr. The reaction was quenched with water, acidified to pH 2 with 1N HCl, and extracted 2 ×, each with 10 mL diethyl ether. The organic phases were dried over MgSO4, filtered, and concentrated. Chromatography on a 2×18 cm column, packed with hexane and eluted with 50 mL each of 2%, 4%, 7%, 10%, and 15% diethyl ether/hexane, furnished 2.734 g of a clear colorless oil in 12 mL fractions 4-16.

Provenance & Evidence