Complexes of indium(III) chloride with bidentate and terdentate nitrogen donors

Abstract

The reactions of indium(III) chloride with several nitrogen donors have been investigated and the far-infrared spectra (500–200 cm.–1) of the resulting complexes measured. Of particular interest are the complexes InCl3bipy1·5, InCl3phen1·5,xMeCN (where x⩽ 1), InCl3phen,H2O, InCl3terpy, and InCl3paphy,2H2O, where bipy = 2,2′-bipyridyl, phen = 1,10-phenanthroline, terpy = 2,2′,2″-terpyridyl and paphy = pyridine-2-aldehyde 2-pyridylhydrazone. While the last two complexes are of the type trans-[InCl3L3] and InCl3B1·5 are ionic, [InCl2B2]+[InCl4B]–, the structure of InCl3phen(H2O) is unknown, although it may be [InCl2phen2]+[InCl4(H2O)2]–. InCl3bipy1·5 reacts with an excess of Ph4AsCl in acetonitrile under reflux to yield Ph4As+[InCl4bipy–],MeCN. The complex InCl3(pyrazine)1·5, which is polymeric with bridging pyrazine molecules, has also been isolated. Factors affecting the structure and stoicheiometry of these and other indium(III) complexes are discussed.