2 ANIONIC INDIUM(III)-THIOCYANATE COMPLEXES WITH POTASSIUM-CENTERED COMPLEX CATIONS

Crystallization of the product of the reaction between impure samples of In(NCS)(3), prepared from InCl3 and KSCN, and 2,2'-bipyridyl (bipy) in tetrahydrofuran solution gave the complex pentakis(tetrahydrofural)-potassium (2,2'-bipyridyl)tetrakis(isothiocyanato)indate-(III), [K(C4H8O)(5)][In(NCS)(4)(C10H8N2)], composed of a potassium cation coordinated by five thf ligands and one S atom of a thiocyanate group, and an octahedral indium-centred anion in which the bipy N atoms are cis and the four thiocyanates are bonded to indium through their N atoms. Crystallization of samples of impure In(NCS)(3) from pyridine in the presence of 18-crown-6 gave the compound (1,4,7,10,13,16-hexaoxacyclooctadecane)potassium bis(pyridine)tetrakis(isothiocyanato)-indate(III) pyridine solvate, [K(C12H24O6)][In(NCS)(4)-(C5H5N)(2)].2C(5)H(5)N, containing an octahedral indium-centred anion in which the pyridine ligands are trans. The potassium in both complexes arises from the contamination of In(NCS)(3) by the KSCN used in its preparation.