Synthesis and crystal structures of two new tin bis(carboranylamidinate) complexes

Abstract

Reaction of 2 equiv. of the lithium carboranylamidinate Li[o-(C2H10B10)C(NCy)(NHCy)] with SnCl2in THF afforded the stannylene compound bis(N,N′-dicyclohexylamidinatocarboranate)tin(II), SnII[o-(C2H10B10)C(NCy)(NHCy)]2(1). A similar reaction of SnCl4with 2 equiv. of Li[o-(C2H10B10)C(NiPr)(NHiPr)] unexpectedly afforded the known solvated pentachloridostannate(IV) salt [Li(THF)4][SnCl5(THF)] as the main reaction product. Small amounts of the new chlorido-tin(IV) bis(carboranylamidinate) bis(N,N′-diisopropylamidinatocarboranate)chloridotin(IV), SnIVCl[o-(C2H10B10)C(NiPr)(NHiPr)][o-(C2H10B10)C(NiPr)2] (2), were isolated as a by-product. Single-crystal X-ray structure analysis revealed aκC,κN-chelating coordination of the carboranylamidinate ligands in both1and2. The Sn atom in1adopts a pseudo-trigonal–bipyramidal coordination under participation of a stereoactive lone pair. In2, a trigonal–bipyramidal coordination of Sn is completed by a chlorido ligand.