Coordination polymers from a highly flexible alkyldiamine-derived ligand: structure, magnetism and gas adsorption studies. Issue 40 (30th July 2015)

• Record Type: Journal Article
• Authors: Hawes, Chris S.; Chilton, Nicholas F.; Moubaraki, Boujemaa; Knowles, Gregory P.; Chaffee, Alan L.; Murray, Keith S.; Batten, Stuart R.; Turner, David R.
• Is Part Of: Dalton transactions. Volume 44:Issue 40(2015)
• Page Start: 17494
• Page End: 17507
• Publication Date: 2015-07-30
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c5dt02323h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Studies into a series of coordination polymers from a new diamine polycarboxylate ligand reveal an interplay between flexibility and material properties. Abstract : The synthesis and structural, magnetic and gas adsorption properties of a series of coordination polymer materials prepared from a new, highly flexible and internally functional tetrakis-carboxybenzyl ligandH4 L derived from 1, 2-diaminoethane have been examined. The compound poly-[Ni3 (HL )2 (OH2 )4 ]·2DMF·2H2 O1, a two-dimensional coordination polymer, contains aqua- and carboxylato-bridged trinuclear Ni II clusters, the magnetic behaviour of which can be well described through experimental fitting and ab initio modelling to a ferromagnetically coupled trimer with a positive axial zero-field splitting parameter D . Compound poly-[Zn2 L ]·2DMF·3H2 O2, a three-dimensional coordination polymer displayingfrl topology, contains large and well-defined solvent channels, which are shown to collapse on solvent exchange or drying. Compound poly-[Zn2 (L )(DMSO)4 ]·3DMSO·3H2 O3, a highly solvated two-dimensional coordination polymer, displayed poor stability characteristics, however a structurally related material poly-[Zn2 (L )(bpe )(DMSO)2 ]·DMSO·3H2 O4 was prepared under similar synthetic conditions by including the 1, 2-bis(4-pyridyl)ethylenebpe co-ligand. Compound4, containing small one-dimensional solvent channels, shows excellent structural resilience to solvent exchange and evacuation, and the evacuated material displays selective adsorption of CO2 over N2 at 273 K in the pressure range 0–1 atm. Each of the coordination polymers displays subtle differences in the conformation and binding mode of the ligand species, with switching between two distinct conformers (X-shaped and H-shaped), as well as a variable protonation state of the central core, with significant effects on the resulting network structures and physical properties of the materials.