isoquinoline

Isoquinoline is a heterocyclic aromatic compound with the formula C9H7N. It is a benzopyridine, formed by a benzene ring fused to a pyridine ring, with the nitrogen atom in the fused ring system. The molecule is planar and aromatic; the nitrogen is weakly basic and can be protonated to give isoquinolinium salts.

Natural occurrence and classes: Isoquinoline occurs in trace amounts in coal tar and serves as a versatile building block in organic synthesis. It is the core structure of many isoquinoline alkaloids found in plants, such as berberine, sanguinarine, and palmatine, which have various biological activities.

Production and applications: Industrially isoquinoline is produced by catalytic dehydrogenation of tetrahydroisoquinoline, which itself can be prepared from established synthetic routes. Isoquinoline and its derivatives are used as precursors for dyes, pharmaceuticals, and other organic compounds.

Safety and handling: Isoquinoline is toxic and can irritate the skin, eyes, and respiratory system. It forms water-soluble salts when protonated and should be handled with appropriate engineering controls and personal protective equipment. Proper storage and disposal procedures are advised to minimize exposure and environmental impact.