Zur Stabilität und Struktur der CuI-Komplexe des Imidazols und Histamins. Chemie des einwertigen Kupfers in homogener, polarer Lösung. 1. Mitteilung
✍ Scribed by C. Sigwart; P. Kroneck; P. Hemmerich
- Publisher
- John Wiley and Sons
- Year
- 1970
- Tongue
- German
- Weight
- 419 KB
- Volume
- 53
- Category
- Article
- ISSN
- 0018-019X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Univalent copper is stabilized in aqueous medium by the non‐protophilic ligand CH~3~CN, allowing ligand displacement reactions to be investigated as if a stable Cu^I^‐hydrate did exist. Under these conditions the formation of Cu^I^‐complexes with imidazole and its derivatives has been studied in polar solution in the absence of Cu^II^. Imidazole (ImH) acts upon Cu^I^ as a bidentate ligand forming polynuclear chains according to the equation
equation image
Histamine reacts in the same way, i. e. the coordination number of Cu^I^ does not exceed 2; by comparison of the complexes of Cu^I^ with histamine and its N‐methyl‐derivatives it is shown that no six‐membered chelate – which sterically would be possible – is built up. Trigonal as well as tetrahedral coordination of Cu^I^ – i. e. chelate formation – in dilute polar solutions are confined to π‐ or d‐acceptor ligands, e. g. bipyridine or methionine. Conclusions are drawn from this on the requirements for redox‐active copper in proteins.