Copper-catalyzed atroposelective hydroarylation of 1-alkynylindoles
Hao-Jin Xu1, Can-Ming Chen1, Zhen Zhang1
1State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
Abstract:
Catalytic enantioselective hydroarylation of alkynes is a concise protocol towards axial, helical, and planar chirality. By using an enantioselective π-acid catalysis strategy, these enantioenriched hydroarylation products could be obtained in a green pathway; however, noble-metal catalysts are unavoidable. Here we report a copper-catalyzed intramolecular atroposelective hydroarylation of 1-alkynylindoles with (hetero)arenes, providing a modular platform for the construction of C─N axially chiral carbazolyl and phenanthryl indoles in excellent yields with good to excellent ee values. Moreover, the constructed C─N axially chiral indoles could be easily diversified to various functional group-containing chiral frameworks, and further applied as a chiral ligand in asymmetric catalysis. Importantly, this reaction represents a rare non-noble metal-catalyzed enantioselective hydroarylation of alkynes by π-acid catalysis.
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