Remarkable aromaticity of cobalt bis(dicarbollide) derivatives: a NICS study

In this work, a novel study on aromaticity for a series of cobalt bis(dicarbollide) derivatives: [3-Co-(1,2-C2B9H9)(2)RX](-) (R, X = H, NH2, NO2, CH3, COH, OCH3, C6H5, Cl) is presented. For this goal the nucleus-independent chemical shift (NICS) calculations were used. Calculated negative NICS is found to be more than two times larger than the relatively high values obtained for other sandwich compounds of transition metals previously studied (Gribanova et al. in Chem Eur J 16(7):2272, 2010).