Kristall- und Molekülstruktur von 6-Ethoxy-12,12-dimethyldibenzo[d,g]-1,3,2,6-dioxaphosphasilocin-6-oxid

Synthesis and Crystal Structure of the Bis(amidinatochelate) Complex ClSb[Ph? C(NSiMe₃)₂]₂ The antimony(III) amidinato complex ClSb[Ph? C(NSiMe₃)₂]₂ was obtained by the reaction of antimony trichloride and N,N,N′-tris(trimethylsilyl)benzamidine in dichloromethane in form of pale-yellow, moisture sensitive crystals. X-ray crystal structure determinations were performed at 20°C and at ?93°C. Crystal data at 20°C: space group P1 , Z = 2, a = 1160.3(2), b = 1305.4(2), c = 1336.5(2) pm, α = 68.32(1), β = 79.79(1), γ = 71.47(1)°; at ?93°C the lattice vectors are 1.20 to 0.85% shorter. In the molecule two Ph? C(NSiMe₃)₂ groups are attached with their N atoms in a chelate manner to the Sb atom. Together with the Cl atom they form an irregular coordination polyhedron about the Sb atom with a stereochemically strongly effective lone electron pair. The SiMe₃ groups show considerable twisting vibrations about the N? Si axes even at ?93°C.     

Tetraphenylantimony <Emphasis Type="Italic">N</Emphasis>-benzoylglycinate: synthesis and structure

Tetraphenylantimony N-benzoylglycinate (I) has been synthesized by the reaction between pentaphenylantimony and N-benzoylglycine in toluene. According to X-ray diffraction data, the antimony atom in a molecule of complex I has a trigonal bipyramidal coordination to the oxygen atom in axial position. The Sb?C_eq, Sb?C_ax, and Sb?O bond lengths are 2.116(6)?2.138(6), 2.183(6), and 2.200(4) Å, respectively. The intramolecular Sb?O=C distance between the carbonyl oxygen atom and the central antimony atom is 3.35(2) Å.     

Element-Element-Bindungen. VI. Kristallines 2-Chlor-1,3,2-benzoxathiastibol – ein mehrfach verknüpftes Koordinationspolymeres

Element-Element-Bonds. VI. Crystalline 2-Chloro-1,3,2-benzoxathiastibole – a Multiply Linked Coordination Polymer Yellow 2-chloro-1,3,2-benzoxathiastibole 4a first prepared by Anchisi and coworkers [3] from o-hydroxythiophenol and antimony trichloride, crystallizes in the monoclinic space group P2₁/n {a = 1109.9(3); b = 610.5(2); c = 1201.5(2) pm; β = 100.35(2)° at ?120 ± 3°C; Z = 4}. An X-ray structure determination (R = 0.029) shows the molecules to form coordination polymeric layers via Sb…?Cl, Sb…?O and Sb…?η²-arene interactions in the solid. Characteristic structural features are Sb? Cl…?Sb? Cl helices (Sb? Cl…?Sb 119°; Cl? Sb…?Cl 95°) and centrosymmetric, four membered Sb₂O₂-rings (O? Sb…?O 64°; Sb? O…?Sb 116°). The ligands set up a strongly distorted octahedron around the antimony atom: Sb? S 242; Sb? Cl 243; Sb…?Cl 328; Sb? O 201; Sb…?O 287; Sb…?C 338 and 341 pm; S? Sb? O 85°; S? Sb? Cl 94°; O? Sb? Cl 92°.     

Synthesis and structure of triphenylantimony diphthalate

Triphenylantimony diphthalate hydrate (I) has been synthesized by the reaction between triphenylantimony and ortho-phthalic acid in the presence of hydrogen peroxide (molar ratio, 1: 2: 1). According to X-ray diffraction data, the antimony atom in a symmetric molecule of compound I (the SbC₃O₂ coordinating moiety has point group C _2v ) has a trigonal bipyramidal coordination. The OSbO axial angle and the CSbC angles in the equatorial plane are 179.83(12)° and 106.04(9)°, 147.93(18)°, respectively. The bond length are 2.153(2) (Sb-O), and 2.110(4), 2.120(3) Å (Sb-C). Intramolecular Sb…O=C contacts (2.802(3) Å) take place in compound I.     

Molecular structure and spectroscopic properties of N-methylmorpholine betaine complex with 4-hydroxybenzoic acid

Crystal structure of the 1:1 complex of N-methylmorpholine betaine (MMB) with 4-hydroxybenzoic acid (4-HBA) has been determined by X-ray diffraction. Crystals are orthorhombic, space group Pna2₁ with a=7.933(2), b=15.336(3), and Z=4, R=0.033. The acid molecule forms two O-H?O hydrogen bonds with two betaine molecules. The COOH group of the acid forms shorter hydrogen bond with betaine (2.587(2) Å), than the hydroxyl group (2.677(2) Å). The carbonyl oxygen atom of the acid also interacts with the methylene hydrogen atom of the betaine through C-H?O hydrogen bond (3.256(2) Å). Thus formed infinite chains parallel to the z axis are connected by other C-H?O hydrogen bonds into layers perpendicular to the x axis. The morpholine ring has a chair conformation with the methyl group in the equatorial position and CH₂COO⁻ group in the axial one. The powder FTIR and Raman spectra and semiempirical calculations of the isolated molecule confirm the structure of the complex investigated. The ¹H and ¹³C spectra indicate that in DMSO-d₆ solution, protons are not transferred from the acid to the betaine molecules.     

[Li(12-Krone-4){(Me3Si)2N}2TiCH2SiMe2NSiMe3] – ein Ionenpaar mit gestreckter Li–C–Ti-Achse

[Li(12-Crown-4){(Me₃Si)₂N}₂TiCH₂SiMe₂NSiMe₃] – an Ion-Pair with a Linear Li–C–Ti-Axis The title compound ( 1 ) has been prepared from Ti[N(SiMe₃)₂]₃ and n-butyllithium in OEt₂/n-hexane in the presence of 12-crown-4. Smaragd-green single crystals of 1 · C₇H₈ which were suitable for X-ray crystallography were formed from toluene solutions at –18 °C. According to the crystal structure determination 1 forms ion pairs between the lithium atom and the CH₂-carbon atom which is member of a planar Ti–C–Si–N heterocycle. The coordination geometry of the Li–C–Ti axis is linear (bond angle 172.8° in average of the two symmetry independent species) with coordination number five at the CH₂-carbon atom.     

Asymmetric nitrogen

Reactions of the Tröger base (1) with HgBr₂ and Mel proceed with the participation of only one N atom. According to the data of X-ray diffraction analysis, the complex [(±)-1]₂·HgBr₂ crystallizes in the achiral space groupP _n . Unlike the complex [(+)-1]₂·HgBr₂, methiodide of (+)-1 in MeOH undergoes racemization at 20°C. The virtual spin-spin coupling constants⁴ J _HH observed for the base (C ₂ symmetry) are transformed into the “usual” constants in the case of the desymmetrized methiodide system.     

Synthesis and structures of organoantimony and organobismuth derivatives of 4-sulfophenol and 2,4-disulfophenol

Tetraphenylbismuth 4-hydroxybenzenesulfonate (I) and tetraphenylantimony 4-hydroxybenzenesulfonate (II) are synthesized in yields up to 80% by the reaction of pentaphenylbismuth and pentaphenylantimony, respectively, with 4-sulfophenol. Compounds I and II are also prepared by the ligand redistribution reaction from pentaphenyl compounds of bismuth and antimony and triphenylbismuth bis(4-hydroxybenzenesulfonate) and triphenylantimony bis(4-hydroxybenzenesulfonate), respectively, in yields up to 87%. The recrystallization of compounds I and II from water gives crystalline hydrates Ph₄BiOSO₂C₆H₄(OH-4) · H₂O (III) and Ph₄SbOSO₂C₆H₄(OH-4) · H₂O (IV). Pentaphenylbismuth and pentaphenylantimony react with 2,4-disulfophenol in acetone, regardless of the ratio of the starting reactants, to form bis(tetraphenylbismuth) 4-hydroxybenzene-1,3-disulfonate (V) and bis(tetraphenylantimony) 4-hydroxybenzene-1,3-disulfonate (VI) in yields up to 74%. According to X-ray diffraction data, coordination of the bismuth atoms in compound I is trigonal-bipyramidal with the axial oxygen atom of the 4-hydroxybenzenesulfonate group (Bi···O 2.764 Å). In compound II, coordination of the Sb atom is tetrahedral (CSbC angles 106.2°–112.3°). In crystal III, the distances between the central atom and the nearest oxygen atoms of the arenesulfonate group and the hydrate water molecule are 3.094 and 3.125 Å, respectively. Crystals V and VI consist of doubly charged anions of 2,4-disulfophenol and several distorted tetrahedral cations of tetraphenylbismuthonium (CBi(1)C, CBi(2)C angles and Bi(1)-C, Bi(2)-C bond lengths vary in the intervals 102.1°–122.7°, 105.4°–114.0° and 2.103–2.230, 2.187–2.209 Å, respectively) and tetraphenylantimonium (CSb(1)C, CSb(2)C angles and Sb(1)-C, Sb(2)-C bond lengths 106.3°–112.2°, 101.3°–122.4° and 2.095–2.110, 2.092–2.123 Å, respectively). The Bi(1) and Sb(2) atoms are coordinated by one of the oxygen atoms of the 2,4-disulfophenol anions (distances Bi(1)···O(3) 2.803, Sb(2)···O(1), 2.704 Å).     

Structure and magnetism of an exchange coupled system: An NMR approach

A binuclear copper(II) complex [Cu₂L(OH)](C1O₄)₂·2H₂O has been synthesized and characterized by X-ray crystallography and¹H-NMR studies. The crystal structure shows that the bridging angles between Cu(l)-O(l)-Cu(2) and Cu(l)-O(2)-Cu(2) are 98.9(2)° and 102.2(2)° respectively. The Cu(l)-Cu(2) distance is 3.0097(12)?. This indicates that the interaction between the two copper atoms is antiferromagnetic in nature. The geometry around Cu(l) is distorted square-pyramid with one water molecule occupying the axial fifth position, whereas, the geometry around Cu(2) is distorted square-planar with weak interactions of one of the perchlorate anion. There are eight molecules present in the unit cell. There is an interdimer interaction between the dimers. The temperature-dependent¹H-NMR chemical shift studies have been performed on six different protons of this complex which reveals that the exchange coupling constant (− 2J) is same for all protons (208 ± 1 cm⁻¹). However, the hyperfine coupling constant (A′) was found to be different in magnitude as well as in sign. We also report solvent dependent NMR properties.     

Specific features of the reaction between tris(5-bromo-2-methoxyphenyl)antimony and 2-oxybenzaldoxime: Structure of bis(μ3-2-oxybenzaldoximato-O,O′,N)-(μ2-oxo)-bis(5-bromo-2-methoxyphenyl)antimony

Bis(μ₃-2-oxybenzaldoximato-O,O′,N)-(μ₂-oxo)-bis(5-bromo-2-methoxyphenyl)antimony, which crystallizes from toluene in the form of a solvate, has been synthesized by the reaction between tris(5-bromo-2-methoxyphenyl)antimony and 2-oxybenzaldoxime in the presence of hydrogen peroxide. According to X-ray diffraction data, the structurally equivalent antimony atoms in a binuclear complex molecule are linked via two tridentate bridging ligands and an oxygen atom and have a distorted octahedral coordination to the C₂O₃N surrounding The trans-angles of the octahedron are CSbO (168.7(1)°), CSbN (164.1(1)°), and OSbO (159.3(1)°), and the bond lengths are Sb-C (2.127(4), 2.159(3) Å) and Sb-N (2.238(3) Å). A molecule contains the three types of Sb-O distances with a bridging oxygen atom (1.950(1) Å), the oxygen atoms of oxy groups (2.002(2) Å), and the oxygen atoms of oxime groups (2.091(2) Å). Sb?OCH₃ intramolecular contacts (3.097, 3.290 Å) also exist.     

Synthesis,Spectral Studies and C-S,C-N Bond Fissions of Some Novel N-[Alkyl (4′- Substituted Phenylthio)] Phthalimides

N-[(4'-Substituted phenylthio)ethyl] phthalimide la-g and their corresponding n-propyl 2a-g, n-butyl 3a-g derivatives have been synthesised. The structure of these compounds were proved by UV,IR, ¹H NMR, ¹³CMR and mass spectra. The ¹H and ¹³C chemical shifts of the adjacent methylene protons and carbons of both the sulfur atom and phthalimido nitrogen group were reasonably correlated using σ° values. The carbon-nitrogen and the carbon-sulfur bond fissions in alkaline and acidic media were discussed.     

Common Features in the Crystal Structures of the Compounds Bis(dimethylstibanyl)oxane and ‐sulfane,and the Minerals Valentinite and Stibnite (Grauspießglanz)

Bis(dimethylstibanyl)oxane ( 1 ) and ‐sulfane ( 2 ), the two simplest organoelement species with an Sb–E–Sb fragment (E = O, S), were prepared by alkaline hydrolysis of bromodimethylstibane and by oxidation of tetramethyldistibane with sulfur [18], respectively. As shown by an x‐ray structure analysis of compound 1 (m. p. < –20 °C; P2₁2₁2₁, a = 675.9(2), b = 803.1(2), c = 1666.8(4) pm at –70 ± 2 °C; Z = 4; R1 = 0.042), the molecules (O–Sb 198.8 and 209.9 pm, Sb–O–Sb 123.0°) adopt a syn‐anti conformation in the solid state and are arranged in zigzag chains along [010] via weak intermolecular O‥Sb interactions (258.5 pm, Sb–O‥Sb 117.8°, O‥Sb–O 173.5°) making use, however, of only one Me₂Sb moiety. Primary and secondary bond lengths and angles agree very well with corresponding values published for valentinite, the orthorhombic modification of antimony(III) oxide [3]. Bis(dimethylstibanyl)sulfane ( 2 ) (m. p. 29 to 31 °C) crystallizes in the uncommon space group P6₅22 (a = 927.8(3), c = 1940.9(7) pm at –100 ± 2 °C; Z = 6; R1 = 0.021). Owing to coordination numbers of (1 + 1) and (2 + 2) for both Me₂Sb groups and the sulfur atom, respectively, molecules with an approximate syn‐syn conformation (S–Sb 249.8 pm, Sb–S–Sb 92.35°) build up a three‐dimensional net of double helices which are linked together by Sb‥S contacts (316.4 pm). These parameters shed more light onto the rather complicated structure and bonding situation in stibnite (antimony(III) sulfide [4]). The molecular packing of compound 2 is compared with the structures of relevant inorganic solids, especially with that of β‐quartz [37].     

Synthesis and structure of tri-<Emphasis Type="Italic">m</Emphasis>-tolylantimony bis(1-adamantanecarboxylate)

Tri(m-tolyl)antimony bis(1-adamantanecarboxylate) (3-MeC₆H₄)₃Sb[OC(O)C₁₀H₁₅]₂ has been synthesized with a yield of 90.0% by the reaction of tri(m-tolyl)antimony with 1-adamantanecarboxylic acid in the presence of hydrogen peroxide in ether. According to X-ray diffraction analysis data, the antimony atom has a distorted trigonal-bipyramidal coordination with the axially positioned oxygen atoms of carboxyl groups. The axial OSbO angle is 173.1(2)°; the equatorial CSbC angles are 112.0(1)°, 112.0(1)°, and 136.0(3)°; the Sb-O distance is 2.109(3)Å; the Sb-C distances are 2.103(5), 2.103(5), and 2.121(7) Å; intramolecular Sb…O(=C) contacts are 3.069(5) Å.     

1H-NMR Study on Inclusion Modes of 2-Chloronaphthalene and α-Cyclodextrin in D2

Abstract

With a 1:1 and a 2:1 host-guest stoichiometry, α-cyclodextrin (α-CD) forms inclusion complexes with 2-chloronaphthalene. From simulations concerning observed chemical-shift differences (Δδ_obs) of proton signals of 2-chloronaphthalene, intrinsic Δδ values are estimated for all the guest protons in the 1:1 and 2:1 inclusion complexes. The intrinsic Δδ values indicate that α-CD first binds to a part of a naphthalene ring bearing a C1 atom to form the 1:1 inclusion complex. In the 1:1 and 2:1 inclusion complexes, the symmetry axes of α-CD are tilted approximately 30° relative to a naphthalene longitudinal axis. In the 2:1 inclusion complex, the association through hydrogen bonding most likely occurs between two α-CD molecules whose symmetry axes are laterally shifted.     

One-step synthesis of pentavalent triphenylantimony derivatives Ph3Sb(OSiR3)2, Ph3Sb(OCH2CH2)2NH and Ph3Sb(OCH2CH2NMe2)2: X-ray molecular structure of Ph3Sb(OSiMe3)2

Pentavalent bis(triorganosiloxy)triphenylantimony derivatives, Ph₃Sb(OSiR₃)₂ (R = Me, Ph), were synthesized by reaction of triphenylantimony with trimethyl- or triphenylsilanol in the presence of tert-butylhydroperoxide by the mild reaction conditions (0-5 °C, 2 h). The reaction of triphenylantimony with diethanolamine in the presence of tert-butylhydroperoxide gave the cyclic compound Ph₃Sb(OCH₂CH₂)₂NH. The mixture of Ph₃SbO and Ph₃Sb(OCH₂CH₂NMe₂)₂ was obtained by the reaction of triphenylantimony with 2-(N,N-dimethylamino)ethanol in the presence of tert-butylhydroperoxide.     

Copper(II) complex with 3-(2-hydroxy-3-sulfo-5-nitrophenylhydrazo)pentane-2,4-dione: Synthesis and structure

The copper(II) complex with 3-(2-hydroxy-3-sulfo-5-nitrophenylhydrazo)pentane-2,4-dione (H₃L) is studied, and its crystal structure is studied by X-ray diffraction analysis. The crystals of [Cu(H₂O)₂]₂(μ-L)₂[Cu(H₂O)₄] (I) are triclinic (space group P \(\bar 1\)) at 100 K, a = 7.085(3), b = 10.373(5), c = 12.265(6) Å, α = 0.842(5)°, β = 104.996(6)°, γ = 99.156(6)°, Z = 1). The C=O and NH groups of hydrazone and the OH and SO₃H groups from the aromatic moiety of the molecule are involved in coordination with the copper(II) atom. In the centrosymmetric trinuclear molecule the central Cu(2) atom has the coordination number six, and the terminal Cu(1) atoms have the coordination number five. The thermal properties of complex I are studied. The complex formation of copper(II) with the H₃L ligand in an aqueous solution at temperatures 298 ± 0.5, 308 ± 0.5, and 318 ± 0.5 K is studied by potentiometric titration. The standard thermodynamic functions of the complex formation are determined.     

Synthesis and crystal structure of the copper(II) valerate complex with nicotinamide

A coordination compound of copper(II) valerate with nicotinamide, [CuL(C₄H₉COO)₂]₂ (I), has been synthesized, and its crystal structure has been determined by X-ray crystallography. The crystals of I are triclinic: a = 9.1245(9) Å, b = 9.8572(6) Å, c = 11.0944(9) Å, α = 73.51(1)°, β = 79.917(6)°, γ = 72.161(7)°, Z = 2, space group $P\bar 1$ . In the centrosymmetric binuclear molecule of I, the copper atoms (Cu...Cu′, 2.621 Å) are linked through four bidentate chelating valerate ligands (av., Cu-O 1.969 Å). The coordination polyhedron of the Cu atom is a tetragonal pyramid with the nitrogen atom of the pyridine ring in the apical position at a longer distance (Cu-N, 2.190 Å).     

Synthesis, characterization and crystal structures of the tetrachlorocuprate and tetrabromocadmate salts of the antimalarial mefloquine

Two new compounds, bis (DL-erythro-α-2-piperydylium-2,8-bis(trifluoromethyl)-4-quinolinemethanol) tetrachlorocuprate(II) tetrahydrate [LH⁺]₂[CuCl₄]^2??4H₂O 1 [L = mefloquine] and bis(DL-erythro-α-2-piperydylium-2,8-bis(trifluoromethyl)-4-quinolinemethanol) tetrabromocadmate (II) bis(methanol) [LH⁺]₂[CdBr₄]^2?·2CH₃OH 2, have been synthesized and characterized by elemental analysis, ¹H-NMR and IR spectroscopy. Single-crystal X-ray diffraction analysis of 1 showed the structure to be ionic with formula unit comprising two protonated monocationic mefloquine molecules of opposite chirality, a tetrachlorocuprate (II) anion and a complement of four water molecules, disordered over several sites. The crystals are orthorhombic, space group Pnma, a = 9.6975(1) Å, b = 29.5385(3) Å, c = 15.9423(1) Å, V = 4566.67(7) ų, Z = 4. The formula unit of compound 2 comprises two protonated monocationic mefloquine molecules, a tetrabromocadmate(II) anion and two molecules of methanol. The crystals are orthorhombic, space group Fdd2, a = 17.2185(5) Å, b = 55.456(2) Å, c = 9.5140(3) Å, V = 9084.6(5) ų, Z = 8. The mefloquine molecule is protonated at the piperidinyl N atom and extensive hydrogen bonding occurs in both crystal structures. The conformation of the mefloquine cation in 1 and 2 is very similar to that recently observed in other salts of the drug, confirming its relevance in the context of antimalarial action.     

Methyl­tri­phenyl­stibonium tetra­fluoro­borate

In the title compound, [Sb(CH₃)(C₆H₅)₃]BF₄, there are four independent cations and anions in the asymmetric unit. The geometry around the Sb atom is distorted tetrahedral, with Sb—C distances in the range 2.077 (4)–2.099 (10) Å and angles at the Sb atom in the range 103.3 (3)–119.0 (4)°.     

Crystal structure of [Cu2(Edta)(Py)2(H2O)2] · 2H2O and [Cu(Im)6]{;Cu(Im)4[Cu(Edta)(Im)]2} · 6H2O, Products of the interaction of (Ethylenediaminetetraacetato)diaquadicopper(II) with pyridine and imidazole

The crystals of [Cu₂(Edta)(Py)₂(H₂O)₂] · 2H₂O (I) and [Cu(Im)₆]{;Cu(Im)₄[Cu(Edta)(Im)]₂} · 6H₂O (II) were isolated as a result of the reaction of an aqueous solutions of Cu₂(Edta) · 4H₂O with pyridine or imidazole, respectively. The crystals were studied by X-ray diffraction. The crystals of I are monoclinic, a = 12.682 Å, b = 6.788 Å, c = 14.834 Å, β = 91.44°, Z = 2, space group P2₁/n. The crystals of II are triclinic, a = 9.118 Å, b = 14.889 Å, c = 15.130 Å, α = 72.59°, β = 72.94°, γ = 82.54°, Z = 1, space group P{ie241-1}. In the centrosymmetric binuclear complex molecule of I, an N atom and two O atoms of the Edta ligand are coordinated to each Cu atom (Cu-N, 2.046 Å; Cu-O, 1.941 and 1.954 Å). The N atom of the pyridine molecule (Cu-N, 1.993 Å) completes the base of an elongated tetragonal pyramid (4 + 1) with the O atom of the H₂O molecule in the apex (Cu-O(w), 2.244 Å). The crystals of II are built of centrosymmetric complex cations [Cu(Im)₆]²⁺ (Cu(1)-N, 2.469, 2.021, and 2.056 Å), centrosymmetric trinuclear complex anions {;Cu(Im)₄[Cu(Edta)(Im)]₂}^2?, and crystal water molecules. In the anion, the central fragment [Cu(Im)₄]²⁺ (Cu(2)-N, 1.985 and 2.023 Å) is bonded to two peripheral complexes [Cu(Edta)(Im)]^2? through atoms O of the Edta ligand (Cu(2)-O, 2.615 Å). In the [Cu(Edta)(Im)]^2? fragment of the complex anion, the Cu(3) atom is bonded to the Edta ligand through the two N atoms and three O atoms (Cu(3)-N, 1.970 and 2.071 Å; Cu(3)-O, 1.966, 1.969, and 2.238 Å) and with the imidazole molecule, through an N atom (Cu(3)-N, 2.397 Å). The coordination polyhedra of the three copper atoms (Cu(1)-Cu(3)) in the structure of II are elongated tetragonal bipyramids (4 + 2). In the structures studied, Edta^4? is a hexadentate chelating/bridging ligand. However, the coordination mode of the ligand in these structures is different: in the binuclear complex I, the Edta ligand is coordinated to each Cu atom through an N atom and two O atoms with the formation of two chelate rings (symmetric (trans) coordination mode), whereas, in the trinuclear complex II, the Edta ligand is coordinated to the Cu(2) atom through an O atom and to the Cu(3) atom through the two N atoms and three O atoms with the formation of three chelate rings (asymmetric (cis) coordination mode).