Structural diversity and variable temperature magnetic properties in copper dimethylmalonate coordination polymers containing dipyridyl-type coligands

Abstract

Four copper dimethylmalonate (dmmal) phases containing long-spanning dipyridyl coligands have been prepared and structurally characterized by single-crystal X-ray diffraction. {[Cu2(dmmal)2(edin)(H2O)2]·3H2O}n (1, edin = N,N′-(ethane-1,2-diyl)diisonicotinamide) and {[Cu2(dmmal)2(bdin)(H2O)2]·2H2O}n (2, bdin = N,N′-(butane-1,4-diyl)diisonicotinamide) both show (6,3) herringbone layers constructed from the edin pillaring of [Cu(H2O)(dmmal)]n chain motifs, that feature embedded equatorial-equatorial bridged {Cu(OCO)}n chains.[Cu2(dmmal)2(bpmp)]n (3, bpmp = bis(4-pyridylmethyl)piperazine) shows a decorated (4,4) grid topology built from bpmp pillared [Cu2(dmmal)2]n ribbon motifs, that feature embedded {Cu2(OCO)4} paddlewheel dimeric units. [Cu2(dmmal)2(bpfp)]n (4, bpfp = bis(4-pyridylformyl)piperazine) shows a 5-connected non-interpenetrated 3D 4466sqp topology, formed from the bpfp pillaring of rectangular equatorial-equatorial bridged [Cu2(dmmal)2]n layers. Variable temperature magnetic studies were carried out on 1, 2 and 4, indicating predominant ferromagnetic superexchange within their equatorial-equatorial {Cu(OCO)}n chain motifs.