Ruthenium-Catalyzed Enantioselective C–H Functionalization: A Practical Access to Optically Active Indoline Derivatives

Ru­(II)-catalyzed enantioselective
C–H activation/hydroarylation
has been developed for the first time, allowing for highly enantioselective
synthesis of indoline derivatives via catalytic C–H activation.
Commercially available Ru­(II) arene complexes and chiral α-methylamines
were employed as highly enantioselective catalysts. Based on a sterically
rigidified chiral transient directing group, multisubstituted indolines
were produced in up to 92% yield with 96% ee. Further transformation
of the resulting 4-formylindoline enables access to an optically active
tricyclic compound that is of potential biological and pharmaceutical
interest.

本研究首次开发了二价钌（Ru(II)）催化的对映选择性碳氢键活化/氢芳基化反应，该反应可通过催化碳氢键活化过程，高对映选择性地合成吲哚啉类衍生物。反应采用商业化可得的二价钌芳烃配合物与手性α-甲胺作为高对映选择性催化剂。基于空间刚性化的手性瞬态导向基策略，多取代吲哚啉的产率最高可达92%，对映体过量值（enantiomeric excess, ee）达96%。对所得的4-甲酰基吲哚啉进行进一步转化，可获得一种具有潜在生物与药学研究价值的光学活性三环化合物。