Structural diversities in Cu(i) and Ag(i) sulfonate coordination polymers and their anion exchange properties

Abstract

Two new Cu(I) compounds, namely [Cu₂(bds)(bpy)₂]·2H₂O (1) and [Cu₄(bds)₂(azpy)₄]·6H₂O (3) (where bds = benzene-1,3-disulfonate, bpy = 4,4′-bipyridine and azpy = 4,4′-azopyridine), and four Ag(I) compounds, namely [Ag₂(bds)(bpy)₂]·2H₂O (2), [Ag₂(bds)(azpy)₂]·4H₂O (4), [Ag(bds)_1/2(bpe)]·3H₂O (5), and [Ag₄(bds)₂(tmdp)₄]·9H₂O (6) (where bpe = 1,2-di(4-pyridyl)ethylene and tmdp = 4,4′-trimethylenedipyridine), have been synthesized, and their structures were determined and characterized by elemental analysis, IR, UV-vis and thermal studies. The structure of the compounds changed from 1D (1 and 2) to 2D (3–5) and interpenetrated 3D (6). In the case of 5, a solid-state [2 + 2] photochemical cycloaddition reaction has been performed. Compound 2 exhibits a reversible anion exchange for perchlorate and permanganate, whereas the other compounds (1, 3–6) exhibit an irreversible anion exchange behaviour for perchlorate. Catalytic studies on 2 indicate Lewis acidity.