4-Chlorobutyric acid (CAS 627-00-9) is a colorless to pale yellow liquid with a pungent odor, used primarily as an organic building block in chemical synthesis and to produce 4-chlorobutyryl chloride. It is a corrosive, combustible material (C4H7ClO2cap C sub 4 cap H sub 7 cap C l cap O sub 2?4?7???2) with a melting point of 14°C14 raised to the composed with power cap C14°? and boiling point of 196°C196 raised to the composed with power cap C196°?. It is soluble in water and used in pharmaceutical research (e.g., as a Levetiracetam impurity) and materials science.