手性磷酸催化剂因其在不对称催化反应中表现出的高效、高对映选择性而受到人们越来越多的关注. 含1,1 -联二萘酚(BINOL)骨架的手性磷酸类催化剂已被广泛用于亚胺的不对称氢转移、Friedel-Crafts 反应和Mannich反应等许多重要的有机合成反应. 手性磷酸具有同时提供质子和接受质子的双功能作用, 因此可以同时活化两个反应底物. 含BINOL骨架的手性磷酸可以通过改变BINOL骨架3,3 -位上的取代基调控空间位阻和手性磷酸的酸性, 因此可以调节反应的对映选择性. 为了合理地设计新的手性磷酸催化剂, 扩大其应用范围, 最近人们对手性磷酸不对称催化反应机理进行了初步的理论计算研究并取得了显著进展.综述了手性磷酸在不对称反应中的部分研究工作, 尤其是理论研究领域的最新成果.
Chiral phosphoric acid has received increasing attention as a highly efficient and enantioselec- tive catalyst. Chiral phosphoric acid with 1,1'-bi-2-naphthol (BINOL) unit has been applied to asymmetric transfer hydrogenation of imines, enantioselective Friedel-Crafts reaction, and asymmetric Mannich reaction etc. Chiral phosphoric acid can act as both proton donor and proton acceptor simultaneously, therefore, it is able to activate both substrates. Both hindrance and pKa of chiral phosphoric acid with BINOL unit can be adjusted by changing the 3,3'-substituents. So the enantioselectivity of chiral phosphoric acid can be modi- fied. More investigations, especially in computational chemistry, on the reaction mechanism catalyzed by chiral phosphoric acid have been carried out to design new chiral phosphoric acid and extend its applica- tions. The applications of chiral phosphoric acid to asymmetric reactions are reviewed, involving the latest computational results.