Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 32, 2018
Previous Article Next Article

Di- and tetranuclear transition metal complexes of a tetrakisguanidino-substituted phenazine dye by stepwise coordination

Author affiliations

Abstract

2,3-Bis- and 2,3,7,8-tetrakisguanidino-substituted phenazines are intensely-coloured dyes that offer two different sites for metal coordination or benzylation, namely the imino nitrogen atoms of the guanidino groups and the phenazine nitrogen atoms. In this work, sequential coordination at both sites is studied, and the effects on the electronic structure and optical properties are analyzed. The step-wise coordination is used to synthesize tetranuclear mixed-valence (CuI)2(CuII)2 and heterobimetallic Cu2Ni2 complexes. Coordination at the guanidino groups switches on a ligand–metal charge-transfer character of electronic transitions in the visible region, leading to a massive intensity gain in the case of copper coordination. The second coordination step with CuI takes place at the phenazine nitrogen atoms and further decreases the ligand frontier orbitals. In the case of two tricoordinated CuI atoms in the product complex, the charge-transfer character of the electronic excitation vanishes, while their energies are very similar. On the other hand, for CuI atoms with a coordination number of only 2, the stronger Cu–N bond leads to a red-shift of the electronic transitions.

Graphical abstract: Di- and tetranuclear transition metal complexes of a tetrakisguanidino-substituted phenazine dye by stepwise coordination

Back to tab navigation

Supplementary files

Article information


Submitted
28 May 2018
Accepted
10 Jul 2018
First published
11 Jul 2018

Dalton Trans., 2018,47, 11016-11029
Article type
Paper

Di- and tetranuclear transition metal complexes of a tetrakisguanidino-substituted phenazine dye by stepwise coordination

R. Lorenz, E. Kaifer, H. Wadepohl and H. Himmel, Dalton Trans., 2018, 47, 11016
DOI: 10.1039/C8DT02176G

Social activity

Search articles by author

Spotlight

Advertisements