naphthalen1ol

1-Naphthol, also known as α-naphthol, is an aromatic alcohol with the chemical formula C10H8O. It consists of a naphthalene ring system bearing a single hydroxyl group at the 1-position. The compound is a pale yellow solid that is sparingly soluble in water and soluble in many organic solvents. As a phenol, it participates in typical reactions of naphthols, including electrophilic substitution and coupling reactions.

Industrial production typically starts from naphthalene by sulfonation to give the corresponding naphthyl sulfonic acids, followed by desulfonation with hot alkali to yield 1-naphthol. The mixture of sulfonic acids can be separated to enrich the 1-isomer. Purification procedures such as crystallization are used to obtain higher purity material.

1-Naphthol is an important intermediate in the manufacture of dyes, particularly as a coupling component in azo dye synthesis, where it couples with diazonium salts to yield orange, red, and brown pigments. It also serves as a precursor to various naphthalene derivatives used in resins, plastics, and pharmaceuticals. In organic synthesis, it is a versatile building block for the preparation of naphthyl ethers and other functionalized aromatics.

Safety: 1-naphthol is irritant to skin, eyes, and the respiratory tract and can be harmful if ingested or inhaled. It should be handled with appropriate protective equipment in a well-ventilated area, and waste should be disposed of according to regulations for hazardous phenols. See also 2-naphthol for a related isomer.