手性氮配体用于对映选择性的铱催化芳基 C-H 键硅氢化反应。

Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering, Peking University, Beijing, China.

Department of Chemistry, University of California, Berkeley, CA, 94720, USA.

Angew Chem Int Ed Engl. 2017 Jan 19;56(4):1092-1096. doi: 10.1002/anie.201609939. Epub 2016 Dec 15.

Iridium catalysts containing dative nitrogen ligands are highly active for the borylation and silylation of C-H bonds, but chiral analogs of these catalysts for enantioselective silylation reactions have not been developed. We report a new chiral pyridinyloxazoline ligand for enantioselective, intramolecular silylation of symmetrical diarylmethoxy diethylsilanes. Regioselective and enantioselective silylation of unsymmetrical substrates was also achieved in the presence of this newly developed system. Preliminary mechanistic studies imply that C-H bond cleavage is irreversible, but not the rate-determining step.

含有配位氮配体的铱催化剂对于 C-H 键的硼化和硅化反应具有很高的活性，但是这些催化剂的手性类似物对于对映选择性硅化反应尚未得到开发。我们报告了一种新的手性吡啶恶唑啉配体，用于对称的二芳基甲氧基二乙氧基硅烷的分子内对映选择性硅化反应。在这个新开发的体系存在的情况下，还实现了非对称底物的区域选择性和对映选择性硅化。初步的机理研究表明，C-H 键的断裂是不可逆的，但不是速率决定步骤。