Nitrile-Rich Borate Anions – Application in Ionic Liquids



The cyano-rich borate anion [B(tceg)2] (tceg = tetracyanoethylene glycolate) has been synthesized in a two-step reaction from Na[B(OMe)4] with two equivalents of the cyanohydrin analogue Me3SiOC2(CN)4OSiMe3. The structures of the starting materials, an isolated intermediate Na2[B2(OMe)2(tceg)3], and Na[B(tceg)2] are discussed. Thermal studies of WCC[B(tceg)2] [WCC = 1-ethyl-3-methylimidazolium (EMIm), 1-butyl-3-methylimidazolium (BMIm), 1-octyl-3-methylimidazolium (OMIm), Me4N, Et4N, and Bu4N], synthesized by salt metathesis, showed that the compounds with EMIm, BMIm, OMIm, and Bu4N have ionic liquid properties. The synthesis, structure, and analytical results of Me3SiOC(CN)3 are discussed as well as the results of its conversion with Na[B(OMe)4].