Kiefer, GregorVrubel, HeronScopelliti, RosarioSeverin, Kay2013-08-282013-08-28201310.1002/ejic.201300551https://infoscience.epfl.ch/handle/20.500.14299/94342WOS:000324926600008Phosphane complexes of the putative formula [CoX2(dppe)] [X = Cl, Br, I; dppe = bis(diphenylphosphanyl)ethane] are frequently used catalyst precursors in cobalt-catalyzed reactions. Despite their widespread use, these complexes have not been structurally characterized. We demonstrate that synthetic procedures for [CoX2(dppe)] afford complexes of the formula [Co4X8(dppe)5] instead. Crystallographic analyses of these complexes reveal an ionic structure with pentacoordinate [CoX(dppe)2]+ cations and a dinuclear [Co2X6(dppe)]2– anion. The bromido and iodido complexes crystallize in two forms, which differ in the geometry of the cation (square-pyramidal vs trigonal-bipyramidal).P ligandsStructure elucidationCrystal structuresCobaltHalidestext::journal::journal article::research article