22bipyridin

2,2'-Bipyridine, sometimes written as 22Bipyridin, is an organic compound with the formula C10H8N2. It consists of two pyridine rings joined at their 2-positions and functions as a bidentate ligand in coordination chemistry. The two pyridine nitrogens donate electron density to a single metal center, typically forming two five-membered chelate rings that stabilize many metal complexes. The molecule is non-planar due to steric interactions between the rings, which affects its bite angle and coordination behavior compared with other bipyridine isomers.

2,2'-Bipyridine is widely used as a ligand for transition metals, including ruthenium, iron, copper, and nickel. It is a standard component in many coordination complexes and in photochemical and electrochemical applications. The complex Ru(bpy)3^2+ (where bpy = 2,2'-bipyridine) is a well-known photosensitizer and has played a central role in light-driven catalysis and solar energy research.

Substituted bipyridines, such as 4,4'-bipyridine and 2,4'- or 2,2'- variants, are related ligands. Substitution can tune steric and electronic properties, bite angle, redox behavior, and solubility, enabling customization for catalysis and materials science.

2,2'-Bipyridine is commercially available and commonly synthesized in laboratory settings. It is typically handled under standard lab safety procedures, as are many pyridine derivatives, and should be stored and used in appropriate containers to minimize exposure.