Ethyl chlorooxoacetate

• α-keto esters.
• Functionalized 3-pyrolin-2-ones.
• Substituted arylglyoxylic acids via Friedel–Crafts acylation.
• Substituted 9,10-phenanthrenequinones.
• Quinoxalinone derivatives.

95-92-1

4755-77-5

The general procedure for the synthesis of monoethyl oxalyl chloride from diethyl oxalate was as follows: a mixture of potassium acetate (20 g), water (30 mL) and diethyl oxalate (29.2 g, 0.2 mol) was stirred and reacted for 2 hours at 70-80 °C. Upon completion of the reaction, the reaction mixture was cooled and concentrated to 30 mL. Subsequently, ethanol (50 mL) and ether (150 mL) were added and the mixed solution was filtered to afford 23.61 g of potassium monoethyl oxalate (76% yield). The dried potassium monoethyl oxalate (20.6 g, 0.13 mol) was pre-mixed with diethyl ether (20 mL) in an ice bath and SOCl2 (30 g, 0.25 mol) was added slowly. The reaction mixture was heated under reflux conditions for 15 hours. At the end of the reaction, the resulting white solid of potassium chloride was removed by filtration, the filtrate was separated and the 125-130 °C fraction was collected by distillation to give 12.22 g of monoethyl oxalyl chloride (69% yield).