Chen Tian, Wang Hao-Yang, Xu Ronghua, Xu Guangqing, Yang He, Sun Jiangtao, Chung Lung Wa, Tang Wenjun
Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University 1 Gehu Road Changzhou 213164 China
Shenzhen Grubbs Institute, Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology Shenzhen 518055 China
Chem Sci. 2025 Jun 17. doi: 10.1039/d5sc03633j.
An asymmetric intramolecular reductive coupling of bisimines has been accomplished for the first time under mild conditions with bis((+)-pinanediolato)diboron as the template, providing the unprecedented chiral dihydrophenanthrene-9,10--diamines in high yields and excellent enantioselectivities. The chiral exocyclic -diamine products have served as effective chiral ligands for asymmetric catalysis. A DFT study highlights the crucial roles of the uncommon twisted-boat pathway (instead of the common chair type) and the steric effect in exclusively forming the -diamines and achieving high enantioselectivity. This reductive coupling protocol represents a significant expansion of the diboron-promoted [3,3]-sigmatropic rearrangement.
在温和条件下，首次以双（（+）-蒎烷二醇合）二硼为模板实现了双亚胺的不对称分子内还原偶联反应，以高收率和优异的对映选择性提供了前所未有的手性二氢菲-9,10-二胺。手性环外二胺产物已用作不对称催化的有效手性配体。一项密度泛函理论研究突出了不常见的扭曲船型途径（而非常见的椅型）和空间效应在专一形成二胺和实现高对映选择性方面的关键作用。这种还原偶联方法代表了二硼促进的[3,3] - 迁移重排的重大扩展。
