Guilty on Two Counts: Stepwise Coordination of Two Fluoride Anions to the Antimony Atom of a Noninnocent Stibine Ligand

Abstract N,N,N'-Tris(trimethylsilyl)benzamidine, [C6H5-C(NSiMe3)N(SiMe3)2], reacts with antimony trichloride in CH2Cl2 solution to form monomeric dichloroantimony-N,N'-bis(trimethylsilyl)- benzamidine, [SbCl2(NSiMe3)2C-C6H5]. Both benzamidine derivatives have been characterized by crystal structure determinations. [C6H5-C(NSiMe3)N(SiMe3)2]: space group P21/c, Z = 4, 2278 observed independent reflexions, R = 0,038. Lattice dimensions (19 °C): a = 1521,0(1); b = 656.7(1); c = 2163,0(1) β = 94,21(1)°. The compound forms monomeric molecules with CN distances of 126,6 pm, and 141,0 pm, respectively, corresponding to C=N̄-SiMe3 and C-N(SiMe3)2 moieties. [SbCl2(NSiMe3)2C-C6H5]: space group P21/c, Z = 4, 2707 observed independent reflexions, R = 0,027. Lattice dimensions (19 °C): a = 1212,7(1); b = 962,1(1); c = 1728,9(1) pm; β = 98,02(1)°. The compound forms monomeric molecules in which the antimony atom is surrounded by two chlorine atoms, and by the N atoms of the benzamidine chelate, forming a distorted trigonal bipyramidal arrangement, which is a consequence of the steric effect of the lone pair on the Sb atom.

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Triphenylantimony(V) complexes with Schiff bases

Australian Journal of Chemistry ◽

10.1071/ch9802749 ◽

1980 ◽

Vol 33 (12) ◽

pp. 2749 ◽

Cited By ~ 14

Author(s):

VK Jain ◽

R Bohra ◽

RC Mehrotra

Keyword(s):

Schiff Bases ◽

Antimony Atom ◽

Azomethine Nitrogen

Twelve new octahedral complexes of the type Ph3Sb(Cl)(OC6H4CR=NR') (where R = H and R' = Me, Et, Pr, Bu, Ph and p-tolyl; R = Me and R' = Me, Bu and Bu') and Ph3Sb(OMe)-(OC6H4CR=NR')(R = H and R' = Me; R = R' = Me) have been synthesized and characterized after purification by recrystallization. The results of the i.r. and 1H n.m.r. spectra of these complexes suggest coordination of azomethine nitrogen to the antimony atom.

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DFT Analysis of the Indium-Antimony-Vacancy Cluster in Silicon

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.245-246.29 ◽

2005 ◽

Vol 245-246 ◽

pp. 29-38 ◽

Cited By ~ 1

Author(s):

M.M. De Souza ◽

Jonathan P. Goss

Keyword(s):

High Temperature ◽

Binding Energy ◽

Vacancy Cluster ◽

Antimony Atom ◽

Teller Effect ◽

High Temperature Anneal ◽

Jahn Teller ◽

Jahn Teller Effect ◽

Low Symmetry ◽

Strong Binding Energy

A cluster comprising of indium, antimony and a vacancy in silicon is analysed using the planewave pseudopotential technique. This cluster has a strong binding energy that inhibits indium diffusion after high temperature anneal cycles. Difficulties associated with the simulation of a vacancy using the supercell approach are initially highlighted. In comparison, the indium-antimony-vacancy cluster reveals stronger distortions and reduction in relaxation volume. The indium atom in the relaxed cluster shows nearly six-fold coordination whereas the antimony atom acquires four neighbours. Due to the low symmetry of the centre, in constrast to the isolated vacancy there is no propensity for a Jahn-Teller effect. It gives rise to two defect levels in the bandgap.

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Reactions of Pentaphenylantimony and Penta-Para-Tolylanimony with Calixarene [4-t-BuC6H2OH(S-2)]4

Bulletin of the South Ural State University series Chemistry ◽

10.14529/chem210105 ◽

2021 ◽

Vol 13 (1) ◽

pp. 47-57

Author(s):

A.N. Efremov ◽

◽

V.V. Sharutin

Keyword(s):

Hydrogen Bonds ◽

Antimony Atom ◽

Tetrahedral Coordination ◽

X Ray Diffraction ◽

Deprotonated Form ◽

X Ray ◽

Bond Lengths ◽

Tert Butyl ◽

Average Value ◽

Intramolecular Hydrogen

Pentaphenylantimony and penta-para-tolylantimony react with calixarene [4-t-BuC6H2OH(S-2)]4 (СArH) by way of arene elimination and formation of the [Ph4Sb]+[СAr]- × TolH (1), [p-Tol4Sb]+[CAr]- × H2O (2) ionic products with a yield up to 96%. The compound has been identified by IR spectroscopy and X-ray diffraction analysis. According to the X-ray diffraction data, compounds 1 and 2 are ionic complexes with solvate molecules of toluene (1) and water (2). The cation has a tetrahedral coordination of the antimony atom with aryl ligands at the polyhedron vertices; the anion is represented by the deprotonated form of p-tert-butylthiacalix[4]arene. The three tert-butyl groups, the phenyl ring and solvated toluene in the structure of compound 1, and two tert-butyl fragments in the structure of compound 2 are disordered over two positions. The tetrahedral coordination of antimony atoms in the cations of compounds 1 and 2 is slightly distorted. The CSbC angles deviate from the theoretical value and vary within 106.0(4)−117.7(4)° (1), 105.75(15)−112.84(15)° (2). The average Sb–C bond lengths are 2.101(3) and 2.106(4) Å in structures 1 and 2, respectively. The [СAr]- anion is in the cone conformation, the upper rim of which is represented by the tert-butyl groups in the para-position, while the lower one is represented by hydroxy groups, one of which is deprotonated. The СAr–O– bond length (1.318(4) (1) and 1.326(4) (2) Å) is less than the average value of the СAr–OH bond lengths (1.338(4) (1) and 1.343(4) (2) Å), which indicates increasing multiplicity of the bond and localization of a negative charge on the oxygen atom. Intramolecular hydrogen bonds with the neiboring O atom are observed. The H∙∙∙O distances are 2.16, 1.69, 1.77 Å in 1 and 1.92, 1.79, 1.76 Å in 2. Dihedral angles between opposite phenoxide rings are 60.64° and 87.07° (1) and 83.85° and 80.42° (2), which indicates somewhat less symmetric anion in structure 1 than in structure 2. The formation of the crystal spatial structure is due to the formation of hydrogen bonds between ions with participation of oxygen and sulfur atoms, as well as СН∙∙∙π–interactions, while the ions form chains in the crystal of compound 1, and layers in the crystal of compound 2. Complete tables of atom coordinates, bond lengths and valence angles are deposited at the Cambridge Crystallographic Data Center (No. 1850118 (1); No. 2013220 (2); [email protected] or http://www.ccdc.cam.ac.uk/data_request/cif).

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The cytotoxicity of organobismuth compounds with certain molecular structures can be diminished by replacing the bismuth atom with an antimony atom in the molecules

The Journal of Toxicological Sciences ◽

10.2131/jts.40.321 ◽

2015 ◽

Vol 40 (3) ◽

pp. 321-327 ◽

Cited By ~ 26

Author(s):

Kumiko Kohri ◽

Eiko Yoshida ◽

Shuji Yasuike ◽

Tomoya Fujie ◽

Chika Yamamoto ◽

...

Keyword(s):

Antimony Atom ◽

Molecular Structures ◽

Bismuth Atom

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Crystal structure and stereoisomerism of Tris(O-ethylxanthato)antimony(III) in its lattice hemiadduct with 4,4'-bipyridyl

Australian Journal of Chemistry ◽

10.1071/ch9780757 ◽

1978 ◽

Vol 31 (4) ◽

pp. 757 ◽

Cited By ~ 9

Author(s):

DL Kepert ◽

CL Raston ◽

AH White ◽

G Winter

Keyword(s):

Crystal Structure ◽

Structure Determination ◽

Electron Pair ◽

Complex Molecule ◽

Lone Pair ◽

Antimony Atom ◽

The Other ◽

Mirror Plane ◽

Crystallographic Symmetry

The preparation and crystal structure determination of the adduct [Sb(S2COEt)3],0.5C10H8N2 is reported. Crystals are triclinic, Pī, a 6.064(3), b 10.825(6), c 17.723(7) Ǻ, α 104.77(4), β 96.78(3), γ 97.14(4)°, Z 2. The compound is a lattice adduct, the bipyridyl molecule being located about a crystallographic centre of symmetry. The complex molecule geometry is unlike that of the compound [Sb(S2COEt)3]; in the latter the molecule has crystallographic symmetry 3, the three equivalent ligands being unsymmetrically coordinated, while in the present molecule the chirality is lost, the molecule conforming to approximate pseudo-m symmetry: two ligands are similar [Sb-S, 2.615(2), 2.892(2); 2.612(2), 2.878(2) Ǻ] and the other, located in the pseudo-mirror plane, is different [Sb-S, 2.477(2), 3.091(2) Ǻ]. Electron-pair repulsion theory shows that the bond angles, the relative bond lengths, and the coexistence of different stereoisomers of this molecule, can be ascribed to the stereochemically active lone pair of electrons being close to the antimony atom.

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