LAUSR

Two novel tartratoborates, namely, K2[(C4H2O6)(B3O4H)](H2O) (1) and KCu2[(C4H2O6)2B](H2O)2.5 (2), have been successfully synthesized by solvothermal reactions. They feature different kinds of structural types based on hybrid borate-tartrate motifs. The structure of compound 1 features a 3D network composed of novel [(C4H2O6)2(B3O4H)2]4- anionic groups interconnected by K+ cations. The [(C4H2O6)2(B3O4H)2]4- anion was formed by the condensation of two (B3O8H)6- groups and two tartrate anions, and such condensation reaction has never been reported previously. Compound 2 exhibits a novel 3D network structure in which 2D {Cu2[(C4H2O6)2B](H2O)2}- layers are further interconnected via K+ ions. The [(C4H2O6)2B]5- anion was formed by the condensation of two tartrate anions with a B(OH)4- unit. Magnetic measurements reveal a dominant antiferromagnetic interaction between neighboring Cu2+ ions in compound 2. Furthermore, UV-vis and infrared spectra and thermal analyses were also performed.