Anion influences on the solid state coordination chemistry of copper–bispyrazole materials

•Syntheses of eight new Cu(I) and Cu(II)–bispyrazole coordination polymers.•Structural influences of anionic components of Cu/bispyrazole/anion materials.•Structural consequences of incorporation of neutral pyrazole components.•Identification of recurring structural motifs and secondary building blocks.

The reactions of the p-xylene-bridged and methylene-bridged bipyrazolyl ligands 1,4-bis[(3′,5′-dimethyl-1H-pyrazole-4′-yl)methylene]benzene (xdpH2) and bis[(3′,5′-dimethyl-1H-pyrazole-4′-yl)]methane (mdpH2) with the appropriate copper salt have provided eight unique members of the Cu/bipyrazole/X system with X = Cl−, Br−, I− and SO42−. The anionic component of [Cu(xdpH2)(H2O)]Cl·H2O (1·H2O) acts as a simple charge-compensating counterion. In contrast, the anionic units of [Cu(xdpH2)Cl2]·2DMF (2·2DMF), [Cu(xdpH2)Cl2(DMF)]·DMF (3·DMF), [Cu2(xdpH2)2Br2] (4), [Cu(mdpH2)Br2] (5), [Cu4(xdpH2)4I4] (6), [Cu2(xdpH2)2(SO4)]·H2O (7·H2O) and [Cu2(xdpH2)2(SO4)]·2H2O (8·2H2O) are involved in bonding to the copper sites. Compounds 1, 4, and 6–8 contain Cu(I) sites while compounds 2, 3, and 5 are polymers of Cu(II). Compounds 1–5 and 7 are one-dimensional, while 8 is two-dimensional and 6 is three-dimensional. Considering the {Cu4I4} clusters of 6 as nodes, the structure is a fivefold interpenetrated framework with individual networks adopting the common {33.123} topology in Schlafli notation.

Graphical abstractThe reactions of organo-bridged bipyrazolyl ligands with the appropriate copper salt provided eight unique members of the Cu/bipyrazole/X system with X = Cl−, Br−, I− and SO42−, of which the double-layered structure of [Cu2(xdpH2)2(SO4)]·2H2O (8·2H2O) is shown.Figure optionsDownload full-size imageDownload as PowerPoint slide