Acetic anhydride Acetyl iodide is an organoiodine compound with the formula CH3COI.

It is formally derived from acetic acid.

Specifically, it is generated by the carbonylation of methyl iodide in the Cativa and Monsanto processes, which are the main industrial processes that generate acetic acid.

[3] Upon treatment with carboxylic acids, acetyl iodide does not exhibit reactions typical of acyl halides, such as acetyl chloride.

Instead, acetyl iodide undergoes iodide/hydroxide exchange with most carboxylic acids:[4]