New types of charge-compensated metallacarboranes: Synthesis, characterization, and structural studies of [(η 5 -RC 2 B 9 H 9 CH 2 NMe 2 )Cr(μ-Cl)Cl] 2 (R = H, Me)

Charge-compensated dicarbollyl chromium complexes of the type [(η5-RC2B9H9 CH2NMe2)Cr(μ-Cl)Cl]2 (R = H 5 and Me 6) were produced by reacting dicarbollylamino aluminum compounds [(η5-RC2B9H9)(η1-CH2NMe2)AlMe] with CrCl3·THF3 in toluene solvent. This new complex is a relatively rare example of a dicarbollylchromium(III) complex containing unpaired electrons. An X-ray crystallographic investigation of 6 reveals a three-legged piano stool structure with a planar dichromium Cr unit containing bridged chloride ions.