Design of readily accessible, noncovalently tunable, and versatile chiral organic salt catalysts incorporating achiral phosphoric acid diesters

Abstract Chiral organic salts, composed of a specific chiral cyclic β-aminoguanidine and an optional achiral phosphoric acid diester, were designed and demonstrated to serve as readily accessible, noncovalently tunable, and versatile asymmetric organocatalysts. These catalysts facilitated the Brønsted base-catalyzed reaction between malonates and nitroolefins and the Lewis base-catalyzed reaction between aldehydes and maleimides. DFT calculations supported the salt’s predicted structure, revealing that the chiral host’s guanidine moiety interacts with the guest phosphate anion via hydrogen bonding.