Asymmetric Nucleophilic Additions Promoted by Quaternary Phosphonium Ion-Pair Catalysts

Chiral quaternary phosphonium ion -pair catalysis showcases a distinctive catalytic and stereoinductive mode arising from the synergy between ionic and noncovalent interactions. Over recent decades, this methodology has been widely adopted to facilitate enantioselective nucleophilic addition reactions, including conjugate addition, Henry reaction, Mannich reaction, Strecker reaction, and hydrophosphonylation. This strategy has been successfully applied to the synthesis of numerous structurally diverse and multifunctionalized molecules, featuring challenging stereogenic centers. This minireview specifically highlights the accomplishments in asymmetric nucleophilic addition facilitated by chiral quaternary phosphonium catalysts. Its purpose is to cultivate interest among researchers, encouraging more engagement in this field and establishing quaternary phosphonium ion -pair catalysis as a potent and dependable tool for synthetic and pharmaceutical chemists.