A structural study of copper(II) carboxylates: Crystal structure and physical characterisation of [Cu₂(2-bromopropanoato)₄(caffeine)₂]

Valach, Fedor; Melník, Milan; Bernardinelli, Gérald; Fromm, Katharina M.

doi:10.1007/s10870-006-9102-8

Back

Journal article

A structural study of copper(II) carboxylates: Crystal structure and physical characterisation of [Cu₂(2-bromopropanoato)₄(caffeine)₂]

Valach, Fedor Slovak University of Technology, Faculty of Chemical and Food Technology, Institute of Physical Chemistry and Chemical Physics, Bratislava, Slovak Republic - Department of Chemistry, University of Basel, Switzerland
Melník, Milan Slovak University of Technology, Faculty of Chemical and Food Technology, Institute of Inorganic Chemistry, Technology and Materials, Bratislava, Slovak Republic
Bernardinelli, Gérald Laboratory of X-ray Crystallography, University of Geneva, Switzerland
Fromm, Katharina M. Department of Chemistry, University of Basel, Switzerland - Department of Chemistry, University of Fribourg, Switzerland

27.06.2006

Published in:

Journal of Chemical Crystallography. - 2006, vol. 36, no. 9, p. 571-580

English Based on the bond-valence sum model the continual transition between the bidentate and monodentate bonding mode of carboxylato group and minimum of Cu–O bond lengths were estimated. The dependence of Cu⋯Cu separation on Cu–N bond length in binuclear Cu(II) carboxylates with caffeine were derived and fitted to the observed data. The crystal structure of [Cu₂(2-bromopropanoato)₄(caffeine)₂] has been determined by X-ray crystallography. The structure consists of centrosymmetric binuclear units where the two Cu atoms are coordinated by four disordered bridging 2-bromopropionates and two caffeine ligands at the apices of a bicapped square prism. Both 2-bromopropionates show disorder of their –Br and –CH₃ substituents. Stacking π·π interactions between the adjacent caffeine molecules link the complex units in 1-D networks. The binuclear structure of the studied compound is consistent with magnetic data and EPR spectrum.

Faculty

Faculté des sciences et de médecine

Department

Département de Chimie

Language