Ethyl Acetoacetate → Ethyl 2-bromo-3-oxobutanoate

Participants

Reaction Conditions

Reaction Steps

3-Oxobutanoic acid ethyl ester (1.26 mL, 10.0 mmol) was added dropwise to a suspension of N-bromosuccinimide (1.78 g, 10.0 mmol) and p-toluenesulfonic acid (10.0 mg, 0.0581 mmol) in methylene chloride (30.0 mL) at 0° C., and the resultant reaction mixture was stirred at 0° C. for 3 h, then warmed to RT and stirred at that temperature for 1 h. The reaction mixture was concentrated in vacuo and the resultant oily solid was treated with hexanes and the resultant suspension was filtered. The solid was washed with additional hexanes and the filtrate was concentrated in vacuo to give a crude oil. Purification by flash column chromatography (100% hexanes to 30% Et2O/hexanes) gave the desired product (1.20 g, 57%) as an oil.

Provenance & Evidence