Stereoselective additions to alkenylphosphonium salts for the synthesis of P-stereogenic compounds

The stereoselective functionalisation of alkenyl P(v) compounds via conjugate additions represents an attractive approach to synthesise chiral organophosphorus compounds. However, asymmetric conjugate additions to alkenyl P(v) compounds are scarce and, in the presence of P-stereogenic centers, diastereoinduction is often low. Here, we report the use of BINOL-based alkenylphosphonium salts for the generation of two non-consecutive P- and C-stereogenic centers via addition of C-nucleophiles in a single operation. These alkenylphosphonium salts behave as activated alkenylphosphonamidate surrogates with increased reactivity and stereocontrol. This methodogy allows the versatile preparation of enantioenriched organophosphorus building-blocks in high yield and stereoselectivity.