Title of Talk

Dicopper Complexes of N-Heterocyclic Carbenes: Synthesis and Catalysis

 

Abstract

A number of phenanthroline functionalized imidazolium and triazolium salts from 2-iodo-1,10-phenanthroline and imidazole and triazole derivatives were prepared. Simple reactions of these imidazolium salts with copper powder at room temperature afforded a series of dinuclear copper(I)-NHC complexes doubly bridged by N-(1,10-phenanthrolin-2-yl)imidazolylidene ligands in excellent yields. The two Phen-NHC ligands are either head-to-head or head-to-tail arranged depending upon the steric repulsion of the substituents. Reactions of imidazolium halides and copper yielded dinuclear complexes [Cu₂(μ-X)(L)₂]X (X = Cl, Br, I) in nearly quantitative yields. The dinuclear [Cu₂(L)₂(μ-MeCN)]²⁺ was similarly obtained through 1,2,4-triazolium salts and copper, and the compound consists of a bridging CH₃CN molecule representing the first example of Cu-NHC complexes with a 3c-2e bond. These Cu(I) complexes have been characterized by NMR spectra, elemental analysis, and further confirmed by X-ray diffraction analysis. These dinuclear copper-NHC complexes are highly active for cycloaddition reaction of alkynes and azides at room temperature.

 

 

References:

1. Liu, B.; Xia, Q.; Chen, W. Angew. Chem. Int. Ed. 2009, 48, 5513

2. Liu, B.; Chen, C.; Zhang, Y.; Li, X.; and Chen, W. Organometallics, DOI: 10.1021/om400738c.

3. Liu, X. and Chen, W. Organometallics, 2012, 31, 6614-6622.

Wanzhi Chen, Professor

 

Department of Chemistry, Zhejiang University,

Hangzhou 310028, P. R. CHINA

e-mail: chenwzz@zju.edu.cn

 

Profile. Dr. Wanzhi Chen born in Shandong, China and obtained his Ph.D. from Dalian Institute of Chemical Physics of Chinese Academy of Sciences in 1991. Postdoc. University of Zaragoza, Spain (1994-1995). Lecturer, Shandong University (1991-1992), Associate professor, Nanjing University (1996-1998), Researcher, National Institute of Materials and Chemical Research, Japan (1998-2000), Guest associate professor, Waseda University Japan (2000-2004). Professor, Zhejiang University (2004-present). Research field: organometallic chemistry and catalysis.

 

 

Selected Publications

1. Liu, X.; Xia, Q.; Zhang, Y.; Chen, C.; and Chen, W. J. Org. Chem. 2013,  78, 8531.

2. Liu, B.; Zhang, Y.; Xu, D.; and Chen, W. Chem. Commun. 2011, 47, 2883.

3. Chen, C. Qiu, H. and Chen, W. Inorg. Chem. 2011, 50, 8671-8678.

4. Liu,B.; Liu,B.; Zhou, Y.; and Chen, W. Organometallics 2010, 29, 1457.

5. B. Liu, Q. Xia, W. Chen, Angew. Chem. Int. Ed. 2009, 48, 5513-5516.