Hydrogen binding in coordination compounds of 3(5)-(4-methoxyphenyl)pyrazole
- 作者：Susann Bergner ; Gotthelf Wolmershä ; user ; Harald Kelm ; Werner R. Thiel
- 关键词：Pyrazole ligands ; Cobalt ; Nickel ; Palladium ; Zinc ; Copper ; Hydrogen bonds ; Crystal structure
- 刊名：Inorganica Chimica Acta
- 出版年：2008
- 期刊代码：40_00201693
- 类别：ch
- 出版时间：20 May 2008
- 卷：361
- 期：7
- 页码：2059-2069
- 文件大小：703 K
摘要
The solid state structures of 3(5)-(4-methoxyphenyl)pyrazole and its coordination compounds with a series of two valent transition metals have been investigated. Since pyrazoles provide not only a nitrogen donor site for the coordination to metal ions, but also an additional N–H function, they are ideal ligands for the formation of hydrogen bound coordination polymers or for the implementation of secondary interactions with other ligands bound to the same central ion, resulting in a rigid ligand environment at the central metal. We chose cobalt, nickel, palladium, copper and zinc as twofold positively charged Lewis acids preferring coordination numbers of four and six to prove the capability of pyrazole to undergo intramolecular hydrogen bonds. In the four-coordinate mode, either tetrahedral (Zn2+) or square planar coordination geometries (Pd2+) are possible, providing different geometric restrictions for hydrogen bonding.