Phenyl isocyanate is an organic compound with the formula C6H5NCO. It is a colorless to pale yellow liquid with a pungent odor and is highly reactive. As an isocyanate, it contains the functional group -NCO, which is known for its ability to react with nucleophiles, such as alcohols and amines, to form urethanes and ureas. Phenyl isocyanate is used in the synthesis of various chemicals, including pharmaceuticals, agrochemicals, and dyes. It is also utilized in polymer chemistry to produce polyurethane materials. Due to its reactivity and potential toxicity, proper safety precautions must be taken when handling this compound.