Cl3CCHO

Cl3CCHO, also known as chloral or 2,2,2-trichloroacetaldehyde, is an organochlorine aldehyde with the formula C2HCl3O. Its structure comprises a trichloromethyl group (CCl3) attached to an aldehyde carbon (CHO). The compound is a dense, colorless to pale yellow liquid that is highly reactive and a strong lachrymator.

Preparation and occurrence: Chloral is typically produced by the chlorination of acetaldehyde under acidic conditions. It can also arise as a byproduct in certain chlorination reactions involving aldehydes. Due to its reactivity, it readily reacts with water and undergoes hydrolysis to form chloral hydrate.

Properties and reactions: Chloral hydrolyzes in water to form chloral hydrate (trichloroacetaldehyde hydrate): CCl3CHO + H2O ⇌ CCl3CH(OH)2. The hydrate is more stable in aqueous solutions. Chloral is miscible with many organic solvents and can participate in further chemical transformations, serving as an electrophile in organic synthesis.

Applications: Historically, chloral is the precursor to chloral hydrate, a sedative and hypnotic used in medicine in the 19th and early 20th centuries. In synthetic chemistry, it has been employed to generate various trichloromethyl derivatives and as a reagent in the preparation of certain intermediates.

Safety and handling: Chloral is a potent irritant and lachrymator with toxic effects if inhaled, ingested, or absorbed through the skin. It reacts with moisture to form chloral hydrate, and it can be incompatible with bases and strong oxidizers. It should be handled in a fume hood with appropriate protective equipment and stored tightly closed in moisture-free conditions.