The New Complexes of Tris(2-Methoxy-5-Bromophenyl)Stibine with Silver Nitrate

By mixing solutions of tris(2-methoxy-5-bromophenyl)antimony and silver nitrate in a methanol : acetonitrile mixture (1:1 vol.), nitrato-O,O'-(acetonitrile)[tris(2-methoxy-5-bromophenyl)antimony]silver complex with the general formula [(C6H3ОMe-2-Br-5)3SbAg(μ2-NO3)(Ме3CN)]2•2[(C6H3ОMe-2-Br-5)3SbAgNO3(Ме3CN)] (1) has been obtained. An addition of silver nitrate solution in the methanol : acetonitrile mixture to the tris(2-methoxy-5-bromophenyl)antimony dioxane solution has led to the formation of a small amount of dark crystals of the ionic complex [(2-MeО-5-Br-C6H3)3SbAg(H2O)Sb(C6H3Br-5-OMe-2)3]+[(2-MeО-5-Br-C6H3)3SbAg(m-NO3)3 AgSb(C6H3Br-5-OMe-2)3]-×3C4H8O2 (2). Complexes 1 and 2 have been characterized by IR spectroscopy, and their structures have been determined by X-ray diffraction analysis. The IR spectra of complexes 1 and 2 contain the bands characterizing the Sb-O, Sb-C, С≡N-, and NO3-group band vibrations. X-ray diffraction analysis of the complexes has been carried out on an automatic four-circle D8 Quest Bruker diffractometer (МоКα radiation, λ = 0.71073 Å, graphite monochromator) at 293 K. Crystallographic characteristics of 1: triclinic, P-1 space group, a = 9.32(3), b = 17.50(7), c = 17.97(5) Å, a = 97.56(14), β = 92.90(19), g = 99.45(19) grad., V = 2859(16) Å3, Z = 2, rcalc = 2.069 g/cm3, 2: monoclinic, С2/с space group, a = 17.417(14), b = 21.041(15), c = 32.01(2) Å, a = 90, β = 97.79(3), g = 90 grad., V = 11624(15) Å3, Z = 4, rcalc = 2.006 g/cm3. In the monomeric and dimeric molecules of crystal 1, nitrate ligands are chelating and bridging, respectively. In the cation of complex 2, the silver atom is bonded to two antimony ligands, the third coordination site is occupied by a water molecule. In the dimeric anion there are one antimony ligand and three bridging nitrate groups surrounding each silver atom.

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

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).

Uranium Concentrations in Tissues and Other Clinical Samples of the Serbian Population

The prevalence of numerous malignant diseases is on the rise, while the mechanism of metal-induced oncogenesis has not been elucidated so far. The aim of this study was to determine the amount of uranium (U) in blood samples of the Serbian population (n = 305) and to perform a comparative analysis with the amounts of U in the blood of patients with thyroid carcinoma (TC, n = 103) and malignant brain tumors (MBTs, n = 157). This study also aimed to extend data on the tissue sample analysis. Uranium was quantified by inductively coupled quadrupole plasma mass spectrometry (ICP-Q-MS). The content of U was approximately 15 times higher in the Serbian population compared to other population groups worldwide that did not suffer from the war, while its amount showed similarities with the countries that directly suffered from the war. Furthermore, the U content was up to twice as high in the blood samples of TC patients compared to the control, while the U content in the TC tissue samples was approximately 10 times higher than in healthy thyroid tissues and showed a tendency to be higher in follicular variant of papillary thyroid carcinoma. However, the highest alterations in U content were obtained in samples of MBT patients, both in liquid clinical samples (serum, lysate, and cerebrospinal fluid) and in tissue samples. The results of this study could highlight the unresolved etiology of TC and MBT. Moreover, the reported results indicated the importance of regular monitoring of U in the blood of the Serbian population.

Synthesis, Sorption and Metallochromy Properties of Organosilicon Derivatives of 1-Acetylguanidine

Increased interest in carbofunctional organosilicon monomers (silanes) and polymers (silsesquioxanes) is associated with the fact that these compounds are promising reagents and building blocks, materials for micro-electronics, agriculture and medicine, complexones, catalysts, and efficient sorbents. Thus, functional polysilsesquioxanes surpass mineral and organic sorbents in sorption properties. Moreover, they have the highest chemical and thermal stability. Along with sorption activity carbofunctional organosilicon compounds of both monomeric and polymeric structures can possess metallochromic properties. All this paves the way for the large-scale development of analytical systems for the creation of new complex test methods for the determination, concentration and separation of metals from solutions. In the present study the functional monomer N-[3-(triethoxysilyl)propyl]acetylguanidine 1 was synthesized by the condensation reaction of 1-acetylguanidine and 3-triethoxysilyl-propylamine. Poly-N-[3-silsesquioxanyl) propyl]acetylguanidine 2 was obtained by hydrolytic polycondensation of compound 1. The composition and structure of compounds 1 and 2 were confirmed by IR and 1H NMR spectroscopy, as well as by elemental analysis. Polymer 2 was studied as a sorbent for ions of heavy metals, such as Hg (II), and noble metals Ag (I), Au (III), Rh (II), Pd (II), Pt (IV) from solutions of their salts in hydrochloric or nitric acid. For polymer 2, the values of static sorption capacities have been calculated. The latter depend on the nature of the metal and have values from 78 mg/g (for platinum) to 366 mg/g for rhodium. The graphs of the degree of metal extraction depending on the sorption time and acid concentration have been plotted. A sorption mechanism is proposed, which is realized due to the chelate interaction of the metal cation (M+) with the amide groups of compounds 1 and 2. The interaction of monomer 1, in the form of indicator paper, and polymer 2, in the powder form, with salts of the studied metals is accompanied by intense specific coloration (metallochromy). Color tables of the samples after their contact with the Ag (I), Au (III), Pd (II), Pt (IV), Rh (III), Hg (II) salts are given.

The Structure Study of Triphenylantimony(V) and Triphenylbismuth(V) Derivatives with Some Unsaturated Carboxylic Acids by IR Spectroscopy

The interaction of triphenylantimony (or triphenylbismuth) with carboxylic acids in the presence of peroxides in ether or THF gave 14 triphenylantimony and triphenylbismuth dicarboxylates Ph3M(O2CR)2 with crotonic, cinnamic, m-nitrocinnamic, p-methoxycinnamic, furylacrylic, vinylacetic and sorbic acids. An aqueous solution of hydrogen peroxide (perhydrol with the peroxide concentration up to 45%) or an 0.8 M ether solution, as well as tert-butyl hydro¬peroxide (98%) were used as initial peroxides. Liquid vinylacetic acid was taken in the amount three times as much as peroxide instead of the required double excess. Solid carboxylic acids had solubility similar to the reaction products, and their separation was more difficult, so they were taken in stoichiometric quantities. Product yields were proved to be 40–90%. The composition of the products was confirmed by the elemental analysis data, 1H and 13C NMR spectroscopy. The position of characteristic signals of symmetric and asymmetric valence vibrations of the main functional groups in the IR spectra has been analyzed, and conclusions about monodentate and bidentate binding of me¬tals to carboxylate ligands are drawn from the difference in their values. Monodentate binding has been recorded in most antimony complexes (crotonate, m-nitrocinnamate, p-methoxycinnamate, furlacrylate, sorbate, vinylacetate), as well as in a number of triphenylbismuth complexes (m-nitrocinnamate, p-methoxycinnamate, furlacrylate, vinylacetate). Bidentate or bordering with monodentate binding has been recorded in the case of antimony only in cinnamate, and in the case of bismuth in crotonate, cinnamate, furylacrylate, and sorbate. The position of the peaks of the valence vibrations of C-H, Sb-C, and Bi-C bonds in the studied carboxylate derivatives, as well as in triphenylantimony and triphenylbismuth molecules, has been compared.

Synthesis of 5-Phenyl-(5,6-Diphenyl-)-2,3-Dihydro-1,2,4-Triazine-3-Thions and Investigation of Their Reactions with 1,2-Dibromoethane

5-Phenyl-(5,6-diphenyl-)-1,2,4-triazine-3(2H)-thions (1,2) were synthesized by condensation of phenylglyoxal monohydrate with thiosemicarbazide and benzyl with thiosemicarbazide hydrochloride, respectively. Phenylglyoxal monohydrate was obtained by oxidation of acetophenone with selenous acid by the Riley reaction, while benzyl (1,2-diphenylethane-1,2-dione) waw obtained by oxidation of (2-hydroxy-1,2-diphenylethanone) benzoin with nitric acid by the known procedure. The compounds 1 and 2 were studied in reactions with 1,2-dibromoethane in various ratios. The interaction of triazinethione 1 with 1,2-dibromoethane in molar ratios of 1:1 and 1:2 led to the formation of a previously unknown 3-[(2-bromoethyl)sulfanyl]-5-phenyl-1,2,4-triazine (3а). Using a double excess of 1,2-dibromoethane increased the yield of compound 3а by 11 %. The interaction of triazinethione 2 with 1,2-dibromoethane in molar ratios 1:1 and 2:1 led to the formation of 3-[(2-bromoethyl)sulfanyl]-5,6-diphenyl-1,2,4-triazine (3b). In the 1H NMR spectra of compounds 3a,b there are signals of aromatic ring protons in the region of 7.23-8.81 ppm, a triplet of protons of the SCH2 group at 3.22 and 4.06 ppm, and a triplet of protons of the CH2Br group at 4.39 and 5.28 ppm. It is of interest that1,2-bis-(5-phenyl-[1,2,4]triazinyl-3-sulfanyl)-ethane is formed in the case of the reaction of compound 1 with 1,2-dibromoethane in the 2:1 ratio of reagents. In the 1H NMR spectra of the latter, in contrast to the spectrum of compound 3a, there is a signal of the S-CH2 group protons, which are equivalent in this structure and form a singlet at 3.79 ppm. Compound 3a was also studied by chromatography-mass spectrometry (direct sample insertion). It should be noted that under the conditions of mass spectrum imaging, the bromine atom is split off and the mass spectrum shows a peak with m/z 216 with an intensity of 38% and no peak of the molecular ion. The peak with the maximum intensity (m/z 116, 100 %) seems to correspond to 4-thia-6,7-diaza-1-azoniumbicyclo[3.2.0]hept-1(5)-ene. Its high intensity is due to the fact that the structure of the 1,2-dihydrotriazetium cation is aromatic.

Structure and Synthesis of Dihalogenodicyanoaurate Complexes [Ph3PR][Au(CN)2Hal2], Hal = Cl, R = Me, СH2Ph; Hal = Br, R = cyclo-C6H11; Hal = I, R = Ph

Interaction of organyltriphenylphosphonium halides with potassium dihalogenodicyanoaurates in water followed by recrystallization of reaction products from acetonitrile or DMSO has been used to synthesize gold(III) ionic complexes [Ph3PMe][Au(CN)2Cl2] (1), [Ph3PCH2Ph][Au(CN)2Cl2] (2), [Ph3PC6H11-cyclo][Au(CN)2Br2] (3), and [Ph4P][Au(CN)2I2] (4), which have been structurally characterized by the X-ray analysis method (CIF files CCDC No. 1901681 (1), 1912903 (2), 1912919 (3), 2048146 (4)). According to the X-ray data crystals 1–4 consist of centrosymmetric square-planar [Au(CN)2Hal2]– anions (the Au–Hal average bond lengths are 2.417(3) Å (1), 2.280(2) Å (2), 2.4203(13) Å (3), and 2.6035(10) Å (4); the Au–C average bond lengths are 2.06(2) Å (1), 2.010(7) Å (2), 2.009(7) Å (3,) and 1.998(6) Å (4)); the phosphorus atoms in organyltriphenylphosphonium cations have a slightly distorted tetrahedral coordination (the P–C bond lengths are 1.782(9)-1.806(8) Å (1), 1.788(4)-1.813(5) Å (2), 1.790(5)-1.813(5) Å (3) and 1.793(6)-1.799(5) Å (4)). The structural organization in crystals 2–4 is caused by the interionic С–H∙∙∙N≡C hydrogen bonds (C–HPh∙∙∙N≡C 2.56 Å (2); C–HPh∙∙∙N≡C 2.43–2.59 Å, C–Hcyclohexyl∙∙∙N≡C 2.47 Å (3), C–HPh∙∙∙N≡C 2.63 Å (4)), while in crystals 1 no significant interionic contacts are observed.

Preparation and Properties of (1-Hydroxyethylidene) Diphosphonic Acid Aminium Salts

An overview of the preparation methods and properties of (1-hydroxyethylidene) diphosphonic acid aminium salts is presented. (1-Hydroxyethylidene) diphosphonic acid with monoethanolamine forms a crystalline compound, which, according to the elemental analysis and XRD data, is ternary C(CH3)(OH)[P(O)O-NH3+CH2CH2OH]3[P(O)(OH)] amine salt. A characteristic feature of the derivatives of (1-hydroxyethylidene) diphosphonic acid and tris (hydroxymethyl)aminomethane is the formation of glassy and resinous products. Their composition Н4L∙4NH2C(CH2OH)3 corresponds to 4 base molecules per 1 tetrabasic acid molecule. The addition of 4 molecules of the primary amine occurs both when the ratio of the initial reagents is 1: 4 and 1: 3. The polymer structure and the presence of strong hydrogen bonds in the Н4L∙4NH2C(CH2OH)3 compound lead to its very low solubility in organic media and good solubility in water. The solubility of Н4L∙4NH2C(CH2OH)3 in methanol is 1.8 g per 100 mL. The reaction of (1-hydroxyethylidene)diphosphonic acid with para-aminobenzoic acid leads to the formation of bis(4-carboxyphenylamine)(1-hydroxyethylidene)diphosphonate C(CH3)(OH)[P(O)(OH)O-NH3+C6H4С(О)ОН]2. In a crystal, this compound consists of the anion of the double-deprotonated (1-hydroxyethylidene)diphosphonic acid C(CH3)(OH)[P(OH)(O)O-]2 and two amine cations NH3+C6H4С(О)ОН. The tetrabasic acid binds 3 molecules of morpholine, giving tris(morpholinium)(1-hydroxyethylidene)diphosphonate H4L•3HN(CH2CH2)2O in the form of a white powder that dissolves well in water, methyl and ethyl alcohols. The solid complex of morpholine with (1-hydroxyethylidene)diphosphonic acid does not crystallize from various solvents, which may be caused by the oligomeric form of morpholine included in the molecule of the complex with H4L.

The Oxidative Addition Reaction of Tris(2-Methoxy-5-Chlorinephenyl)Antimony With Trifluoropropionic Acid

The interaction of tris(2-methoxy-5-chlorophenyl)antimony with 3,3,3–trifluoropropionic acid in the presence of hydrogen peroxide (1:2:1 mol) in ether proceeds according to the oxidative addition reaction scheme with the formation of bis(3,3,3-trifluoropropionyl)tris(2-methoxy-5-chlorophenyl)antimony [(MeO-2)(Cl-5)C6H3]Sb[OC(O)CH2F3]2. The IR spectra of compound 2, recorded on a Shimadzu IRAffinity-1S Fourier transform IR spectrometer in a KBr pellet in the region of 4000–400 cm–1, contain absorption bands of carbonyl groups, which are shifted to the low-frequency vibration region in comparison with the IR spectra of the initial acids. According to the X-ray diffraction data obtained on a Bruker D8 QUEST diffractometer, compound 1 has the following crystallographic parameters of the unit cell: crystal size 0.23×0.21×0.08 mm3, space group P21/n, а = 8.883(7), b = 21.184(15), c = 13.642(15) Å, α = 90.00°, β = 107.34(3)°, γ = 90.00°, V = 2451(4) Å3, ρcalc = 1.587 g/cm3, Z = 4; crystal 2 has the following crystallographic parameters of the unit cell: 0.3×0.25×0.08 mm3, P21/c, а = 12.00(5), b =16.81(7), c =16.30(9) Å, α =90.00°, β =108.3(3)°, γ =90.00°, V =3121(25) Å3, ρcalc = 1.704 g/cm3, Z = 4. The antimony atom in 2 has a distorted trigonal-bipyramidal coordination with carboxylate ligands in axial positions. The OSbО angles are 174.2(5)°, the sums of the СSbC angles in the equatorial plane are 360°, the axial Sb–O bonds equal 2.073(15), 2.092(15) Å, and the equatorial Sb–С bonds equal 2.05–2.13 Å, which is close to the sum of the covalent radii of the atoms. The intramolecular Sb∙∙∙OМе distances (3.035(3), 3.037(3), 2.992(4) Å (1), 3.03(2), 3.119(17), 3.147(19) Å (2)), as well as Sb∙∙∙OMe for compound 2 (3.232(19), 2.99(2) Å), are much smaller than the sum of the van der Waals radii of atoms.

Reaction of Pentaphenylphosphorus with Hexachloroplatinic Acid

Tetraphenylphosphonium hexachloroplatinate (1) was synthesized by the interaction of pentaphenylphosphorus with hexachloroplatinic acid in acetone. The recrystallization of complex 1 from dimethylsulfoxide gave tetraphenylphosphonium dimethylsulfoxidopentachloroplatinate (2). The compounds have been characterized by IR-spectroscopy and X-ray analysis. The absorption bands characterizing stretching vibrations of the phenyl groups are present in the IR spectra, recorded on a Shimadzu IRAffinity-1S Fourier spectrometer in the 4000–400 cm–1 area in KBr pellets. According to the X-ray analysis, the compound unit cell parameters are: triclinic syngony, space group (1, 2), а = 10.205(10), b = 10.970(15), c = 12.160(11) Å (1), а = 7.7667(4), b = 13.3069(7), c = 14.2562(7) Å (2), a = 73,65(4)°, β = 80.64(3)°, g = 77.48° (1), a = 80.972(4)°, β = 88.205(4)°, g = 89.199(4)° (2), V = 1272(2) Å3 (1), 1454.38(13) Å3 (2). The crystals of complexes 1 and 2 consist of the tetrahedral tetraphenylphosphonium cations and octahedral anions. In cations the phosphorus atoms have a slightly distorted tetrahedral environment (the CPC angles are 107.8(3)-113.2(3)° (1), 105.9(3)–112.9(3)° (2), the P-C distance is 1.785(6)-1.805(6) Å (1), 1.783(7)–1.791(6) Å (2). Platinum atoms in the anions of complexes 1 and 2 are hexacoordinated. In complex 2 the dimethyl sulfoxide ligand is coordinated with the Pt atom via the sulfur atom 2.290(2) Å. Complete tables of coordinates of atoms, bond lengths and valence angles are deposited at the Cambridge Structural Data (CCDC 1865783, 829586 http://www.ccdc.cam.ac.uk).