An Unusual Mixed-Valence Cu(I)−Cu(II) 3-D Framework

The reaction of Cu(CH3CN)4ClO4 with 2-pyridylacrylic acid (2-HPYA) affords an unusual mixed-valence Cu(I)−Cu(II) 3-D framework {[Cu(II)(2-PYA)2]3·[Cu(I)(2-PYA)]2·(H2O)2}n (1) with a novel topology which features Cu(II) dimeric units (or paddle-wheel unit). The almost perpendicular coordinating direction between the N atom of pyridyl and the O atom of carboxylate groups may be responsible for the formation of such a novel network.