Dipotassium Maleate with Boric Acid

Abstract

In the title compound, poly[(3-boric acid)-4-maleato-dipotassium], [K2(C4H2O4){B(OH)3}] n , there are two independent K+ cations, one bonded to seven O atoms (three from boric acid and four from maleate), and the other eight-coordinate via three boric acid and four maleate O atoms and a weak 1-type coordination to the C=C bond of the maleate central C atoms. Hydrogen bonding links the boric acid ligands and maleate dianions, completing the packing structure. © International Union of Crystallography 2007.