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

Reaction of 2 equiv. of the lithium carboranylamidinate Li[o-(C(2)H(10)B(10))C(NCy)(NHCy)] with SnCl(2) in THF afforded the stannylene compound bis(N,N'-dicyclohexylamidinatocarboranate)tin(II), Sn(II)[o-(C(2)H(10)B(10))C(NCy)(NHCy)](2) (1). A similar reaction of SnCl(4) with 2 equiv. of Li[o-(C(2)H(10)B(10))C(N (i) Pr)(NH (i) Pr)] unexpectedly afforded the known solvated penta-chlorido-stannate(IV) salt [Li(THF)(4)][SnCl(5)(THF)] as the main reaction product. Small amounts of the new chlorido-tin(IV) bis-(carboranylamidinate) bis(N,N'-diiso-propylamidinatocarboranate)chloridotin(IV), Sn(IV)Cl[o-(C(2)H(10)B(10))C(N (i) Pr)(NH (i) Pr)][o-(C(2)H(10)B(10))C(N (i) Pr)(2)] (2), were isolated as a by-product. Single-crystal X-ray structure analysis revealed a κC,κN-chelating coordination of the carboranylamidinate ligands in both 1 and 2. The Sn atom in 1 adopts a pseudo-trigonal-bipyramidal coordination under participation of a stereoactive lone pair. In 2, a trigonal-bipyramidal coordination of Sn is completed by a chlorido ligand.