Synlett
DOI: 10.1055/a-1500-9673
letter

Palladium-Catalyzed Aerobic Oxidative Carbonylation of Amines Enables the Synthesis of Unsymmetrical N,N′-Disubstituted Ureas

Honglan Zeng
a  Jiangsu Key Laboratory of Biofunctional Materials, Key Laboratory of Applied Photochemistry, School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road No.1, Nanjing 210023, P. R. of China
,
Hongyan Du
a  Jiangsu Key Laboratory of Biofunctional Materials, Key Laboratory of Applied Photochemistry, School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road No.1, Nanjing 210023, P. R. of China
,
Xu Gong
a  Jiangsu Key Laboratory of Biofunctional Materials, Key Laboratory of Applied Photochemistry, School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road No.1, Nanjing 210023, P. R. of China
,
Jie Zhang
a  Jiangsu Key Laboratory of Biofunctional Materials, Key Laboratory of Applied Photochemistry, School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road No.1, Nanjing 210023, P. R. of China
,
Wei Han
a  Jiangsu Key Laboratory of Biofunctional Materials, Key Laboratory of Applied Photochemistry, School of Chemistry and Materials Science, Nanjing Normal University, Wenyuan Road No.1, Nanjing 210023, P. R. of China
b  Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Nanjing 210023, P. R. of China
› Author Affiliations
The work was sponsored by the Natural Science Foundation of China (21776139 and 21302099), the Natural Science Foundation of Jiangsu Province (BK20161553), the Natural Science Foundation of Jiangsu Provincial Colleges and Universities (16KJB150019), the China Scholarship Council, and the Priority Academic Program Development of Jiangsu Higher Education Institutions.


Abstract

A ligand-free palladium-catalyzed aerobic oxidative carbonylation of amines for the synthesis of ureas, particular unsymmetrically N,N′-disubstituted ureas, which cannot be accessed by any other palladium-catalyzed oxidative carbonylation of amines to date, is presented. An array of symmetrical and unsymmetrical ureas were straightforwardly synthesized by using inexpensive, readily available, stable, and safe amines with good to excellent yields under a pressure of 1 atm. This novel method employs oxygen as the sole oxidant and offers an attractive alternative to transition-metal-based oxidant systems

Supporting Information



Publication History

Received: 31 March 2021

Accepted after revision: 06 May 2021

Publication Date:
06 May 2021 (online)

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