paranaphthoquinone

Paranaphthoquinone, also known as para-naphthoquinone or 1,4-naphthoquinone, is an organic compound with the molecular formula C10H6O2. It is one of the two common isomers of naphthoquinone, in which two carbonyl groups are fused to the naphthalene ring at positions 1 and 4, giving a para relationship between the carbonyls. The molecule is planar and highly conjugated, contributing to distinctive redox properties.

Paranaphthoquinone is typically described as a pale yellow crystalline solid with limited water solubility, soluble in many organic solvents. It is produced commercially by oxidation of naphthalene or related precursors; in laboratory settings it can be prepared by oxidation of naphthalene derivatives using oxidants such as nitric acid, chromic reagents, or oxygen under catalytic conditions.

Chemically, paranaphthoquinone behaves as an electron-poor electrophile and participates in redox reactions. It serves as an oxidant in certain organic syntheses and provides a versatile building block for functionalization to dyes, pharmaceuticals, and other quinone-derived compounds. Reduction of 1,4-naphthoquinone yields naphthohydroquinone derivatives, enabling access to related benzoquinone systems.

Applications of paranaphthoquinone include its use as an intermediate in the manufacture of dyes and quinone-containing compounds, and it is studied for quinone redox chemistry in laboratory settings. It also appears as a reference reagent in various oxidation–reduction protocols.

Safety and handling: Quinones can be irritating to skin, eyes, and the respiratory tract and may be hazardous if ingested or inhaled. Paranaphthoquinone can undergo redox cycling to generate reactive oxygen species under certain conditions. It should be handled with appropriate personal protective equipment and disposed of according to applicable regulations.