BINAP

<p>BINAP (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) is an <a href="/facts/Organophosphorus_compound/kNgIF93U">organophosphorus compound</a>.  This <a href="/facts/Optical_isomerism/wjPv5J3y">chiral</a> <a href="/facts/Diphosphines/hBqT62GC">diphosphine</a> <a href="/facts/Ligand/6etB3qeW">ligand</a> is widely used in <a href="/facts/Chiral_synthesis/5hJe37TL">asymmetric synthesis</a>.  It consists of a pair of 2-diphenylphosphino<a href="/facts/Naphthalene/RU2sV8mN">naphthyl</a> groups linked at the 1 and 1′ positions.  This <a href="/facts/C2-Symmetric_ligands/yeaTGaRC">C2-symmetric framework</a> lacks a <a href="/facts/Stereocenter/t3XGwk1Q">stereogenic atom</a>, but has <a href="/facts/Axial_chirality/hNRww7Vc">axial chirality</a> due to restricted rotation (<a href="/facts/Atropisomer/IWGqaLsT">atropisomerism</a>). The barrier to <a href="/facts/Racemization/t4C1SIXQ">racemization</a> is high due to <a href="/facts/Steric_hindrance/TnX5c8HG">steric hindrance</a>, which limits rotation about the bond linking the naphthyl rings.  The <a href="/facts/Dihedral_angle/C9WEJsuS">dihedral angle</a> between the naphthyl groups is approximately 90°.  The natural <a href="/facts/Bite_angle/tEFLuAJv">bite angle</a> is 93°.
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BINAP open-in-new

BINAP