Unprecedented (3,9)-connected (42.6)3(46.621.89) net constructed by trinuclear mixed-valence cobalt clusters

A solvothermal reaction of Co2O3, CoSO4, pyridine-3,5-dicarboxylic acid, and H2O2 in an aqueous MeCN solution yielded a three-dimensional coordination framework [Co-3(OH)(pdc)(3)]center dot H2O (1) (pdc = pyridine-3,5-dicarboxylate). Compound 1 shows an unprecedented (3,9)-connected (4(2).6)(3)(4(6).6(21).8(9)) topology in which hydroxycentered mixed-valence Co-3(OH)(CO2)(6) clusters act as nine-connected nodes of a tricapped trigonal prism, and pdc groups act as three-connected nodes of trigonal geometry.