Syntheses, characterization and X-ray structure of potassium Hydrotris(2-mercaptothiazolyl)borate, KMt, and potassium hydrotris(methimazole) borate, KTm

Potassium hydrotris(2-mercaptothiazolyl)borate, KMt, (1) and potassium hydrotris(2-methimazole), KTm, (2), were prepared by reacting the appropriate amine thiol with KBH4. They were characterized by spectroscopic methods and elemental analysis. Solid state structures of KMt.4H(2)O and compound 2 were determined by X-ray diffraction analyses. The softer nature of the anion in the former as compared to 2 is indicated by the lack of interaction of the anion with the cation, that has water molecules in its coordination sphere. In KMt.4H(2)O the geometry around the potassium cation is distorted octahedral and in 2, distorted square pyramidal. In 2 the potassium ion is coordinated to two sulfur atoms of one hydrotris(methimazole) borate unit and to other three sulfur atoms belonging to neighboring KTm units. Both compounds have a polymeric structure.