Oksalilkloridin

Oksalilkloridin, known in English as oxalyl chloride, is an organochlorine compound with the formula (COCl)2. It is a colorless, highly reactive liquid that fumes in air and is sensitive to moisture. In organic synthesis, oksalilkloridin is used primarily to convert carboxylic acids into acid chlorides, which then serve as versatile intermediates for making esters, amides, and anhydrides.

Production and handling

Oxalyl chloride is typically prepared by reacting oxalic acid with thionyl chloride, producing oxalyl chloride along with sulfur dioxide and hydrogen chloride. The substance is highly reactive toward water, alcohols, and other nucleophiles, undergoing hydrolysis to oxalic acid and hydrochloric acid. Because of its reactivity and corrosivity, it is handled under strictly dry conditions in a well-ventilated fume hood, with appropriate personal protective equipment. It is stored in tightly closed, moisture-free containers, away from bases and moisture sources.

Reactivity and applications

In addition to enabling the formation of acid chlorides from carboxylic acids, oksalilkloridin participates in a range of acylation reactions used to synthesize esters, amides, and other carbonyl-containing derivatives. It is used in pharmaceuticals, agrochemicals, and polymer- or resin-related syntheses where activation of carboxylic acids is required. Its strong lachrymatory and corrosive properties demand careful handling and containment.

Safety and environmental notes

Oksalilkloridin is highly corrosive and irritant. It reacts vigorously with water, releasing hydrochloric acid and carbon dioxide. Release to the environment should be minimized; spills require immediate containment and neutralization under proper safety procedures.

See also

Phosgene, thionyl chloride, carbonyl chlorides.