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 [Co₃(OH)(pdc)₃]·H₂O (1) (pdc = pyridine-3,5-dicarboxylate). Compound 1 shows an unprecedented (3,9)-connected (4².6)₃(4⁶.6²¹.8⁹) topology in which hydroxycentered mixed-valence Co₃(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.