Syntheses and crystal structures of three indium pyrazolyl complexes two of which contain novel bridging features

Abstract

The complexes [(HB(Pz*)₃)In(µ-Pz*)₂(µ-OH)In((Pz*)₃BH)]I·2MeCN 1, [In(HB(Pz*)₃)I₂(HPz*)]·0.5C₆H₁₂ 2, and [In₂(Pz**)₄I₂ONa₂(THF)₂] 3, where HPz* is 3,5-dimethylpyrazole and HPz** is 3,5-di-tert-butylpyrazole, have been prepared and their crystal structures determined. The presence in 1 of bridging Pz* and in 2 of monodentate HPz* given that this was not a starting material is attributed to the moisture sensitivity of tris(pyrazolyl)borates. The indium ions in 1 are bridged by two Pz* groups and an hydroxide ion, whereas in 3 the only bridge directly between the indium ions is an oxygen dianion. The four-co-ordinate donor set of the indium ion in 3 is formed by the bridging oxygen dianion, an iodide ion and the nitrogens of two Pz** groups. The remaining nitrogens of the Pz** co-ordinate to a sodium ion, which itself effectively bridges Pz** groups on adjacent indium ions.