P-Chiral phosphine

P-Chiral phosphines are organophosphorus compounds of the formula PRR′R″, where R, R′, R″ = H, alkyl, aryl, etc. They are a subset of chiral phosphines, a broader class of compounds where the stereogenic center can reside at sites other than phosphorus. P-chirality exploits the high barrier for inversion of phosphines, which ensures that enantiomers of PRR'R" do not racemize readily. The inversion barrier is relatively insensitive to substituents for triorganophosphines.^[2] By contrast, most amines of the type NRR′R″ undergo rapid pyramidal inversion.

Two P-chiral "Kwon phosphines".^[1]

Research themes

Most chiral phosphines are C₂-symmetric diphosphines. Famous examples are DIPAMP and BINAP. These chelating ligands support catalysts used in asymmetric hydrogenation and related reactions. DIPAMP is prepared by coupling the P-chiral methylphenylanisylphosphine.

P-Chiral phosphines are of particular interest in asymmetric catalysis. P-Chiral phosphines have been investigated for two main applications, as ligands for asymmetric homogeneous catalysts and as nucleophiles in organocatalysis.^[1]