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Kudinov, Alexander R.; Perekalin, Dmitry S.; Rynin, Stanislav S.; Lyssenko, Konstantin А.; Grintselev-Knyazev, Gennadii V.; Petrovskii, P. V.

doi:10.1002/1521-3757(20021104)114:21<4286::aid-ange4286>3.0.co;2-6

Cited by 19 publications

(21 citation statements)

References 6 publications

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“…For example, the B(9)-S(1) bond length in salt 1 (1.8816(9) Å) is close to the corresponding bond length in the neutral nido carborane 9 SMe 2 7,8 C 2 B 9 H 11 (1.884(2) Å) 23 and is only slightly smaller than the B(9)-S(1) bond lengths in the closo metallocarborane complexes (1.900(2)-1.921(3) Å). 19, 24 The main geometric parameters of the carborane frag ment in the contact ion pair are also close to the corre sponding characteristics in the isolated anion. Small dif ferences (0.009-0.014 Å) are observed for the bonds, which are involved to a greater or lesser extent in interac tions with the sodium cations.…”

Section: Resultsmentioning

confidence: 99%

Nature of weak inter- and intramolecular interactions in crystals. 5. Interactions Na...H—B in a crystal of sodium salt of charge-compensated nido-carborane [9-SMe2-7,8-C2B9H10]−

et al. 2005

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The character of electron density distribution in the C 2 B 3 open face, the influence of the SMe 2 group on the character of electron density distribution, and the nature of the so dium-anion interaction were studied based on the data of high resolution X ray diffraction study of crystals of the sodium salt of charge compensated nido carborane [9 SMe 2 7,8 C 2 B 9 H 10 ] -and quantum chemical calculations for the Na...H-B bonded dimer, the isolated [9 SMe 2 7,8 C 2 B 9 H 10 ] -anion, and the [7,8 C 2 B 9 H 10 ] 2-dianion. The character of electron density distribution in the C 2 B 3 open face is analogous to the electron distribution in the cyclopentadienyl ligand. In nido carborane, a substantial charge redistribution takes place compared to that observed in the closo analogs. The topological analysis of the electron density distribution function demonstrated that the cation-anion interactions are determined pre dominantly by Na...H-B contacts. The total energy of these contacts in the {[9 SMe 2 7,8 C 2 B 9 H 10 ]Na(thf) 2 } 2 dimer estimated from X ray diffraction data is 11.74 kcal mol -1 .Key words: charge compensated nido carboranes, isolobality, nido carborane salts with alkali metals, quantum chemical calculations, Na...B-H contacts, electron density distribu tion, topological theory of Atoms in Molecules, high resolution X ray diffraction study.Alkali metal salts with anionic 11 vertex nido carbo ranes are widely used as starting compounds in the syn thesis of metallocarboranes. 2-5 However, their structures both in solution and in the solid state remained unknown until very recently. In the last years, it has been demon strated that these salts exist predominantly as contact ion pairs both in crystals 6,7 and in solution. 8 The coordination mode of cations in anionic nido car boranes depends substantially on the cation size. In lithium salts with the charge compensated [9 L 7,8 C 2 B 9 H 10 ] -anions (L = SMe 2 or NMe 3 ) and the [7,8 C 2 B 9 H 10 ] 2-dianions, η 5 coordination at the C 2 B 3 open face of the carborane is the main coordination mode, whereas so dium salts are characterized by exo coordination at the B(10)B(11)B(6) face. 6,7In the case of exo coordination, the sodium-anion interaction can be either analogous to interactions in exo nido Os, Ru, 9,10 and Rh 11 complexes with 3c-2e metal...H-B bonds or occur through an interaction of the sodium cation with the electron density localized at the center of the triangular face and on the boron atoms.Actually, the negative charge in carboranes is distributed not only between the hydrogen atoms of the B-H bonds 12 but also over the surface of the triangular face. 13-15 From the geometric standpoint (Na...B and Na...H distances), 6 both types of interactions in sodium salts with the [9 L 7,8 C 2 B 9 H 10 ] -anion are equally probable. In struc tural studies 16,17 of small and medium sized carborane salts with alkali and alkaline earth metal cations, it was hypothesized that the cations interact predominantly with boron atoms. In contrast, Na...H-B ...

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Section: Resultsmentioning

confidence: 99%

Nature of weak inter- and intramolecular interactions in crystals. 5. Interactions Na...H—B in a crystal of sodium salt of charge-compensated nido-carborane [9-SMe2-7,8-C2B9H10]−

et al. 2005

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“…10 Cation 5 was isolated as a salt with the PF 6 - Compounds 4 and 5•PF 6 are colorless crystalline com pounds, which are stable in air both in the solid state and as solutions in CH 2 Cl 2 and Me 2 CO. Their structures were confirmed by elemental analysis and 1 H and 11 B NMR spectroscopy ( Table 1). The 1 H NMR spectrum of com plex 4 shows four signals for the CH protons of two carborane ligands.…”

Section: Resultsmentioning

confidence: 93%

“…An analogous situation has been ob served earlier for the rhodium analog (η 9 SMe 2 7,8 C 2 B 9 H 10 )Rh(η 7,8 C 2 B 9 H 11 ). 10 Compounds 2 and 5•PF 6 were studied by X ray dif fraction. The structures of complex 2 and cation 5 are shown in Figs 1 and 2, respectively.…”

Section: Resultsmentioning

confidence: 97%

“…The distance ∆ 1 in Cp*Ir(7,8 C 2 B 9 H 11 ) (1.579 Å) is 0.02 Å shorter than that in 5, which can be consid ered as evidence for stronger binding of the dicarbollide dianion compared to anion 1. The distance between the metal atom and the C 2 B 3 plane in the rhodium com plex [Cp*Rh(η 9 SMe 2 7,8 C 2 B 9 H 10 )] + (1.625 Å) 10 is also longer than that in Cp*Rh(7,8 C 2 B 9 H 11 ) (1.596 Å). 12 The distance between the iridium atom and the plane of the Cp* ligand (∆ 2 ) in cation 5 (1.833(3) Å) is some what longer than that in [Cp*IrCp] + (1.80 Å), 14 which can be attributed to a weaker back donation due to the stronger accepting character of ligand 1 compared to Cp -.…”

Section: Resultsmentioning

confidence: 99%

“…These rhodium complexes were used for the synthesis of other derivatives containing the (η 9 SMe 2 7,8 C 2 B 9 H 10 )Rh fragment. 10 In the present study, we synthesized sandwich iridium complexes with ligand 1 and established the structures of (η 9 SMe 2 7,8 C 2 B 9 H 10 )Ir(η cod) (2) and [Cp*Ir(η 9 SMe 2 7,8 C 2 B 9 H 10 )]PF 6 by X ray diffraction.…”

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Sandwich iridium complexes with the monoanionic carborane ligand [9-SMe2-7,8-C2B9H10]−

et al. 2006

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The reaction of the [(η 9 SMe 2 7,8 C 2 B 9 H 10 )IrBr 2 ] 2 complex with Tl[Tl(η 7,8 C 2 B 9 H 11 )] afforded the iridacarborane compound (η 9 SMe 2 7,8 C 2 B 9 H 10 )Ir(η 7,8 C 2 B 9 H 11 ). The cat ionic complex [Cp*Ir(η 9 SMe 2 7,8 C 2 B 9 H 10 )] + PF 6 -(5•PF 6 , Cp* is pentamethylcyclo pentadienyl) was synthesized by the reaction of [Cp*IrCl 2 ] 2 with Na[9 SMe 2 7,8 C 2 B 9 H 10 ]. The structures of (η 9 SMe 2 7,8 C 2 B 9 H 10 )Ir(η cod) (cod is 1,5 cyclooctadiene) and 5•PF 6 were established by X ray diffraction.

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A 15‐Vertex Heteroborane

et al. 2006

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Following the synthesis [1] and characterization [1,2] of the first supraicosahedral heteroborane, 4-(h-C 5 H 5 )-4,1,6-closoCoC 2 B 10 H 12 , 35 years ago, experimental work in the area has advanced relatively slowly, with only sporadic reports of new species. Presently, the number of reported 13-vertex compounds, mainly MC 2 B 10[3] (where M is a metal center) but occasionally M 2 C 2 B 9 , [4] is only of the order of 150. Moreover, a mere handful of closed 14-vertex compounds have been reported, all except one being M 2 C 2 B 10 , [5] and no examples of species with 15 or more vertices in the polyhedron.The prevalence of metallacarboranes amongst the supraicosahedral heteroboranes reflects that such polyhedra generally contain an increasing number of degree-six vertices. Thus, for example, Brown and Lipscomb, [6] in considering hypothetical triangulated (deltahedral) structures for [B n H n ] 2À for n = 13-24, find that the number of degree-six vertices generally increases with increasing n, and the largest single-cage deltahedron currently known, Ge 18 4À (in [Pd 2 @ Ge 18 ] 4À ), has recently been shown to contain six degree-six vertices.[7] Metal atoms or fragments, having relatively diffuse frontier orbital compared to {BH} fragments, are able to stabilize such structures, and thus in supraicosahedral metallacarboranes it is the metal atom(s) which tend to occupy the degree-six site(s). [3][4][5] However, fuelled by the results of later theoretical calculations [8] suggesting that [B n H n ] 2À ions with n ! 16 might adopt alternative structures which need not be fully triangulated and which are computed [9] to be progressively more favorable than the ubiquitous [B 12 H 12 ] 2À ion, we and others have renewed experimental efforts towards preparing progressively larger supraicosahedral heteroboranes with limited numbers of, or no, metal heteroatoms. As a result, the field of supraicosahedral heteroborane chemistry is currently undergoing an impressive renaissance. In 2003 we reported the first supraicosahedral carborane, [10] having 13 vertices and, interestingly in view of the predictions of

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Cited by 19 publications

References 6 publications

Nature of weak inter- and intramolecular interactions in crystals. 5. Interactions Na...H—B in a crystal of sodium salt of charge-compensated nido-carborane [9-SMe2-7,8-C2B9H10]−

Nature of weak inter- and intramolecular interactions in crystals. 5. Interactions Na...H—B in a crystal of sodium salt of charge-compensated nido-carborane [9-SMe2-7,8-C2B9H10]−

Sandwich iridium complexes with the monoanionic carborane ligand [9-SMe2-7,8-C2B9H10]−

A 15‐Vertex Heteroborane

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