Chiral phosphoric acid

In organic chemistry, chiral phosphoric acids are esters of phosphoric acid H₃PO₄ that have chiral backbones. Well known examples include cyclic diesters derived from the BINOL and TADDOL motifs. These compounds are used in asymmetric catalysis as chiral Brønsted acids and/or hydrogen-bond donors.^[2] The conjugate bases are also used in generating chiral ion pairs.^[3]

Structure of a common class of BINOL-derived chiral phosphoric acids. Catalysts of this type are also known as Akiyama–Terada catalysts (after Takahiko Akiyama and Masahiro Terada). Common examples of Ar include Ar = 4-NO₂-C₆H₄, 9-anthracenyl, and 2, 4, 6-iPr₃-C₆H₂ (commonly known as TRIP^[1]).

In one example, they are used to catalyze the asymmetric desymmetrization by monohydrolysis of a diester.^[4]