Synthesis 2021; 53(03): 538-546
DOI: 10.1055/s-0040-1707387
paper

Efficient Access to Isoquinolines via Rhodium-Catalyzed Oxidative Annulation of Pyridyl C–H Bonds Directed by Carbonyl with Internal Alkynes

Lijun Shi
a   State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. of China
b   University of the Chinese Academy of Sciences, Beijing 100049, P. R. of China
,
Mingshan Wen
a   State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. of China
,
Fuwei Li
a   State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P. R. of China
› Author Affiliations
This work was funded by the National Key Research and Development Program of China (2018YFB1501600), the National Natural Science Foundation of China (21773271 and 21972151), the Light of West China of the Chinese Academy of Sciences (CAS), and the Key Research Program of Frontier Sciences, CAS (QYZDJSSW-SLH051).


Abstract

An efficient synthesis of amino-substituted isoquinolines via Rh(III)-catalyzed oxidative [2+2+2] annulation of pyridines with alkynes has been developed, which is cooperatively enabled by a directing carbonyl and steric hindrance adjacent to the amino group of the pyridine, via a six-membered rhodacyclic intermediate without coordination with the pyridinic nitrogen. The establishment of this C–H activation strategy also paves the way for other oxidative transformations of heterocyclic C–H bonds.

Supporting Information



Publication History

Received: 20 July 2020

Accepted after revision: 18 August 2020

Article published online:
15 September 2020

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