Selective synthesis of nitrogen bi-heteroarenes by a hydrogen transfer-mediated direct α,β-coupling reaction
Xiu-Wen Chen1, He Zhao1, Biao Xiong1
1Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510641, China. minzhang@scut.edu.cn.
Abstract:
By an external hydrogen transfer-mediated activation mode, we herein demonstrate a new palladium-catalyzed direct α,β-coupling of different types of N-heteroarenes. Such a selective coupling reaction proceeds with the advantages of operational simplicity, high atom-economical efficiency, and use of safe and abundant i-propanol as the activating agent, offering a practical way to access nitrogen bi-heteroarenes. Preliminary exploration has revealed that the obtained bis-1,10-phenanthroline 2qq' as a ligand is capable of improving a copper catalyst for C-C bond formation. The work reported in this paper has built an important basis for the creation of extended π-conjugated systems that are of high significance in biological, medicinal, materials and synthetic organic chemistry as well as catalysis.
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