Conformation-Dependent Electron Donation of Nido-Carborane Substituents and Its Influence on Phosphorescence of Tris(2,2′-bipyridyl)ruthenium(II) Complex

Half-Sandwich Nickelacarboranes Derived from [7-(MeO(CH2)2S)-7,8-C2B9H11]−

New carboranyl thioethers 1-MeO(CH2)nS-1,2-C2B10H11 (n = 2, 3) were prepared by the alkylation of the trimethylammonium salt of 1-mercapto-ortho-carborane with 1-bromo- 2-methoxyethane and 1-bromo-3-methoxypropane, respectively. Their deboronation with cesium fluoride in ethanol gave the corresponding nido-carboranes Cs[7-MeO(CH2)nS-7,8-C2B9H11] (n = 2, 3). The reactions of Cs[7-MeO(CH2)2S-7,8-C2B9H11] with various nickel(II) phosphine complexes [(dppe)NiCl2] and [(R’R2P)2NiCl2] (R = R’ = Ph, Bu; R = Me, R’ = Ph; R = Ph, R’ = Me, Et) were studied and a series of nickelacarboranes 3,3-dppe-1-MeO(CH2)2S-closo-3,1,2-NiC2B9H10 and 3,3- (R’R2P)2-1-MeO(CH2)2S-closo-3,1,2-NiC2B9H10 (R = R’ = Bu; R = Me, R’ = Ph; R = Ph, R’ = Me, Et) was prepared. The molecular crystal structure of 3,3-dppe-1-MeO(CH2)2S-closo-3,1,2-NiC2B9H10 was determined by single-crystal X-ray diffraction.

Charge-Compensated Derivatives of Nido-Carborane

This review summarizes data on the main types of charge-compensated nido-carborane derivatives. Compared with organic analogs, onium derivatives of nido-carborane have increased stability due to the stabilizing electron-donor action of the boron cage. Charge-compensated derivatives are considered according to the type of heteroatom bonded to a boron atom.