BINAP is an abbreviation

Abbreviation

An abbreviation is a shortened form of a word or phrase. Usually, but not always, it consists of a letter or group of letters taken from the word or phrase...

 for the organophosphorus compound 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl. This chiral ligand

Ligand

In coordination chemistry, a ligand is an ion or molecule that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from...

 is widely used in asymmetric synthesis

Chiral synthesis

Enantioselective synthesis, also called chiral synthesis, asymmetric synthesis or stereoselective synthesis, is organic synthesis that introduces one or more new and desired elements of chirality...

. It consists of a pair of 2-diphenylphosphinonaphthyl

Naphthalene

Naphthalene is an organic compound with formula . It is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings...

 groups linked at the 1 and 1´ positions. This C₂-symmetric framework lacks stereogenic atom

Stereocenter

A stereocenter or stereogenic center is an atom, bearing groups such that an interchanging of any two groups leads to a stereoisomer.A chirality center is a stereocenter consisting of an atom holding a set of ligands in a spatial arrangement which is not superposable on its mirror image...

, but has axial chirality

Axial chirality

Axial chirality is a special case of chirality in which a molecule does not possess a stereogenic center but an axis of chirality – an axis about which a set of substituents is held in a spatial arrangement that is not superposable on its mirror image...

 due to restricted rotation (atropisomer

Atropisomer

Atropisomers are stereoisomers resulting from hindered rotation about single bonds where the steric strain barrier to rotation is high enough to allow for the isolation of the conformers. The word atropisomer is derived from the Greek a, meaning not, and tropos, meaning turn...

ism). The barrier to racemization is high due to steric hindrance, which limits rotation about the bond linking the naphthyl rings.