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Voloshin, Ya. Z.; Varzatskii, Оleg А.; Vorontsov, Ivan I.; Antipin, M. Yu.; Lebedev, A. Yu.; Belov, Alexander S.; Palchik, A.V.

doi:10.1023/a:1025641025505

Cited by 15 publications

(6 citation statements)

References 15 publications

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“…The nucleophilic substitution of the hexachloroclathrochelate precursor Co(Cl 2 Gm) 3 (BC 6 F 5 ) 2 with a pentafluorophenylthiolate anion gave the target hexasulfide monomacrobicyclic complex Co((C 6 F 5 S) 2 Gm) 3 (BC 6 F 5 ) 2 and the mixed-valence Co III Co II Co III bis-clathrochelate [Co((C 6 F 5 2 Co (Scheme 2) as a side product. Two plausible pathways for the formation of this bis-cage complex (Scheme 3) may be suggested.…”

Section: Resultsmentioning

confidence: 99%

“…For the cobalt(II) clathrochelate with an electronic configuration d 7 , the Jahn-Teller structural effect is observed as an alternation of these Co-N distances: they vary within 0.23 Å in the Co II N 6 -polyhedron and within 0.06 Å in the Fe II N 6 -and Co III N 6 polyhedra. In the absence of steric hindrances, the TAP geometry is more preferable for both electronic configurations d 6 and d 7 ; so the capping cobalt(II) ion with a CoO 6 -coordination polyhedron in (Co((C 6 F 5 S) 2 -Gm) 3 (BC 6 F 5 )) 2 Co adopts such a geometry. 8-40.7°due to the rigidity of their chelate NvC-CvN ribbed fragments.…”

Section: X-ray Structuresmentioning

confidence: 99%

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Molecular design of cage iron(ii) and cobalt(ii,iii) complexes with a second fluorine-enriched superhydrophobic shell

et al. 2015

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Pentafluorophenylboron-capped iron and cobalt(II) hexachloroclathrochelate precursors were obtained by the one-pot template condensation of dichloroglyoxime with pentafluorophenylboronic acid on iron and cobalt(II) ions under vigorous reaction conditions in trifluoroacetic acid media. These reactive precursors easily undergo nucleophilic substitution with (per)fluoroarylthiolate anions, giving (per)fluoroarylsulfide macrobicyclic complexes with encapsulated iron and cobalt(II) ions; nucleophilic substitution of the cobalt(II) hexachloroclathrochelate precursor with a pentafluorophenylsulfide anion gave the target hexasulfide monoclathrochelate and the mixed-valence Co(III)Co(II)Co(III) bis-clathrochelate as a side product. The complexes obtained were characterized using elemental analysis, MALDI-TOF mass spectrometry, IR, UV-Vis, (57)Fe Mössbauer (for the X-rayed iron complexes), (1)H, (11)B, (13)C and (19)F NMR spectroscopies and by X-ray diffraction; their redox and electrocatalytic behaviors were studied using cyclic voltammetry and gas chromatography. As can be seen from the single-crystal X-ray diffraction data, the second superhydrophobic shell of such caged metal ions is formed by fluorine atoms of both the apical and ribbed (per)fluoroaryl peripheral groups. The main bond distances and chelate N=C-C=N angles in their molecules are similar, but rotational elongation (contraction) along the molecular C3-pseudoaxes, accompanied by changes in the geometry of the corresponding MN6-coordination polyhedra from a trigonal prism to a trigonal antiprism, allowed encapsulating Fe(2+), Co(2+) and Co(3+) ions. The nature of an encapsulated metal ion and its oxidation state affect the M-N bond lengths, and, for cobalt(ii) clathrochelate with an electronic configuration d(7) the Jahn-Teller structural effect is observed as an alternation of the Co-N distances. Pentafluorophenylboron-capped hexachloroclathrochelate precursors, giving stable catalytically active metal(I)-containing intermediates due to the electron-withdrawing effect of their six ribbed chlorine substituents, were found to show moderate electrocatalytic activity in a 2H(+)/H2 hydrogen-forming reaction. In the case of their ribbed-functionalized sulfide derivatives, the strong electron-withdrawing (per)fluoroaryl groups do not stabilize the reduced electrocatalytically active metal(i)-containing species as their mesomeric effect is absent or substantially decreased by steric hindrances between them.

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Section: Resultsmentioning

confidence: 99%

Section: X-ray Structuresmentioning

confidence: 99%

Molecular design of cage iron(ii) and cobalt(ii,iii) complexes with a second fluorine-enriched superhydrophobic shell

et al. 2015

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“…An analogous method was executed for the synthesis of 2,2-dimethylhydrazinomethylsilatrane (39) by using sodium methoxide as catalyst 34 and 1-(3-mercaptopropyl)silatrane (40) by simply heating the reactants. 35 Sometimes, two reaction pathways can be employed for the synthesis of new silatranes; either by the transesterification of the corresponding silanes with amine or by modification of the precursor silatrane by using suitable reagents. The two pathways have been used in order to develop 1-(trialkylstannylthioalkyl)silatranes, which consists of transesterification as well as treatment of sulfur containing 1-organosilatranes with trialkylalkoxystannanes or hexaethyldistannoxane.…”

Section: Varinder Kaur Chahalmentioning

confidence: 99%

Silatranes: a review on their synthesis, structure, reactivity and applications

2011

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This critical review summarizes progress of the rapidly developing and very active field of silatrane chemistry. The first part of the review deals with general synthetic approaches used to synthesize different silatranes. The most interesting feature of silatranes, i.e., variation of Si-N bond length on the basis of the axial substituent of Si, and other structural features, are described in the second part with special emphasis on crystallographic and theoretical studies. It is followed by a discussion on the reactivity of various silatranes. Silatranes have now gained acceptance for a wide variety of applications which are summarized in the last section of review. Some of them have extensive interest due to their medical use to heal wounds or stimulate hair-growth (pilotropic activity), biological properties, pharmacological properties e.g. antitumor, anticancer, antibacterial, anti-inflammatory, fungicidal activity, stimulating effect in animal production and seed germination effects. The review focuses on the extended potential of silatranes in sol-gel processes, mesoporous zeotypes, atomic force microscopy, commercial products such as adhesion promoters, polymer formation and rubber compositions. This critical review will be helpful for general researchers, experts, advanced undergraduates and newcomers working on silatrane chemistry as this review presents greater emphasis on synthesis and characterization, structural properties, reactivity and applications of silatranes in the field of biology, material science, sol-gel chemistry, pharmaceutics, agriculture and medicine (311 references).

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“…These compounds have been used widely as a ''molecular scaffold" for the design of polytopic, polyfunctional and polynuclear systems [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. In particular, the ribbed-functionalized clatrochelates both with the inherent and with the terminal closo-borate substituents synthesized recently have been proposed as new radiopharmaceuticals for boron neutron capture therapy of cancer [12,17].…”

Section: Introductionmentioning

confidence: 99%

“…TP-TAP distortion u angle of the coordination polyhedron of the encapsulated iron(II) ion is equal to 20.4°. This value is also characteristic of the boroncapped tris-nioximate iron(II) complexes [20]: several structures of these complexes were obtained by X-ray crystallography (FeNx 3 (BFc) 2 Á 2CCl 4 [30], FeNx 3 (Bn-C 4 H 9 ) 2 [31], FeNx 3 (BCH 2 -CH@CH 2 ) 2 [32], FeNx 3 (Bn-C 16 H 33 ) 2 [32], FeNx 3 (BC 6 H 3 (OCH 3 ) 2 ) 2 Á CHCl 3 [33], FeNx 3 (BC"C-C 6 H 5 ) 2 Á C 6 H 5 CH 3 [33] and FeNx 3 (BAd) 2 Á C 6 H 12 [16]). TP-TAP distortion u angles for these compounds vary in a wide range from 9.5°to 22.9°and the u angle value for 5b is inside of this range.…”

Section: Introductionmentioning

confidence: 99%