A new look at the structure and reactivity of 10-vertex nido-dicarbaboranes

AIM analysis of electron density distribution based on B3LYP calculations, carried out for nido-5,6-C2B8H12 and its anion [nido-C2B8H11]−, and the data of IR spectroscopy lead to conclusion that the formally 6-member face is of greater size due to incorporation of adjacent triangular face and two extra-hydrogen atoms. In nido-5,6-C2B8H12 open face is characterized by complete absence of electron density. The Laplacian of electron density is used to predict the sites of electrophilic attack, which position was shown to depend on a number of extra-hydrogen atoms. The predictions are in agreement with known experimental data.