Diversity-oriented synthesis of P-stereogenic and axially chiral monodentate biaryl phosphines enabled by C-P bond cleavage

Abstract

Chiral monodentate biaryl phosphines (MOPs) have attracted intense attention as chiral ligands over the past decades. However, the creation of structurally diverse chiral MOPs with both P- and axial chirality is still in high demand but challenging. Here, we show a distinct strategy for diversity-oriented synthesis of structurally diverse MOPs containing both P- and axial chirality enabled by enantioselective C-P bond cleavage. The key chiral PdII intermediates, generated through the stereoselective oxidative addition of C-P bond, could be trapped by alkynes, R3Si-Bpin, diboron esters or reduced by H2O/B2pin2, leading to enantioenriched structurally diverse MOPs in excellent diastereo- and enantioselectivities. Based on the outstanding properties of the parent scaffolds, the P- and axially chiral monodentate biaryl phosphines serve as excellent catalysts in asymmetric [3 + 2] annulation of MBH carbonate affording the chiral functionalized bicyclic imide.