Cobalt bis(dicarbollide) anion and its derivatives

Synthesis and study ofC-substituted methylthio derivatives of cobalt bis(dicarbollide)

“…The most known of them, cobalt bis(dicarbollide) [3,3 0 -Co(1,2-C 2 B 9 H 11 ) 2 ] À attracts increasing interest from researchers working in various elds from medical chemistry to [6][7][8][9][10][11] materials science [12][13][14][15][16][17][18] to due to its extraordinary high stability, low toxicity 19 and almost unlimited possibilities for chemical modication. 20,21 Recently, we suggested that cobalt bis(dicarbollide) can be used as a structural element in the design of molecular switches. 22 Molecular switches are molecules or supramolecular complexes that can exist in two or more stable forms that differ in the mutual orientation of their components and can be converted readily from one state to another by various external stimuli such as heat, light, chemicals, etc.…”

Focus on Chemistry of the 10-Dioxane-nido-7,8-dicarba-undecahydrido Undecaborate Zwitterion; Exceptionally Easy Abstraction of Hydrogen Bridge and Double-Action Pathways Observed in Ring Cleavage Reactions with OH− as Nucleophile

“…1 H and 13 C-NMR spectra of 4then show inequivalent signals of all eight CH 2 groups attached to different, oxygen and nitrogen sites of aminophenol. Also aromatic signals of the central phenol unit in 13 C-NMR are split into two sets. After metathesis to potassium salt these signals shrunk together and only 3 overlapping signals could be observed in the range of CH 2 protons in 1 H-NMR.…”

“…For chemical analyses the Me 4 N + or Bu 4 N + salts were used. 13 C, and 11 B-NMR spectra were measured on a Varian Mercury 400 Plus and a on Jeol 600 MHz spectrometers. The spectra of all compounds were measured immediately after dissolution in particular deuterated solvent, usually acetonitrile-d 3 unless otherwise stated.…”

“…This compound belongs to a large and rapidly growing family of species that contain an ether ring attached to the boron cage via an oxonium atom [9][10][11][12]. All other members are derived from closo-borate ions such as cobalt bis(dicarbollide) [13,14], decaborate [15,16], dodecaborate [17][18][19], or 1-carba-undecahydroundecaborate [20]; most of which have been used in numerous emerging applications, among others, advanced materials [21,22], organic conducting polymers [23,24], radionuclide partitioning [25,26], biology, and medicine [8,[27][28][29][30][31][32][33][34][35][36][37]. Surprisingly enough, the nidosystem from this family of compounds, namely compound 1, has largely remained outside the stream of main interest, despite its potential for the introduction of open-cage boron polyhedra to functional molecules and materials.…”

Ferrocene and Transition Metal Bis(Dicarbollides) as Platform for Design of Rotatory Molecular Switches

“…Other highly stable sandwich complexes that have potential as component of molecular switches are bis(dicarbollide) complexes of transition metals, which are isoelectronic analogs of metallocene ( Figure 20 ). The first synthesis of these complexes has been reported in middle 1960s and their chemical properties are well studied now [ 54 , 55 , 56 , 57 , 58 ]. Unlike cyclopentadienyl ligands, the dicarbollide ligand contain two carbon atoms and three boron atoms in open pentagonal face, that results in energy nonequivalence of different rotamers of bis(dicarbollide) complexes.…”