RCOCl, known as an acyl chloride, is a type of organic compound that contains a carbonyl group (C=O) bonded to a chlorine atom. It is derived from carboxylic acids by replacing the hydroxyl group (-OH) with a chlorine atom. Acyl chlorides are typically reactive and are used in various chemical reactions, including the synthesis of esters and amides. These compounds are important in organic chemistry and are often utilized in the production of pharmaceuticals and agrochemicals. Due to their reactivity, RCOCl can easily react with water, alcohols, and amines, making them valuable intermediates in chemical synthesis.