Biphenyl   CAS No.: 92-52-4

Biphenyl is mainly used as a heat exchanger and in organic synthesis.

Biphenyl (chemical formula: C12H10) is a compound formed by combining two phenyl groups. Colorless to light yellow flake crystal, with special fragrance. Commonly used as organic synthesis precursors, derivatives including benzidine, diphenyl ether, octabromodiphenyl ether, polychlorinated biphenyls and so on. Biphenyls are found naturally in coal tar, crude oil and natural gas. Insoluble in water, but soluble in organic solvents.

The bonds between biphenyls are free to rotate, but when there are large groups at the four adjacent sites, the rotation is blocked, resulting in blocked isomers. Compounds of this type, such as BINAP, can act as chiral ligands. For biphenyl, the torsion Angle of the equilibrium state is 44.4°, and the energy barrier at 0° and 90° is 6.0kJ/mol and 6.5kJ/mol, respectively. [1]

Substituted biphenyls can be prepared by coupling reactions such as Suzuki reaction and Ullmann reaction.