Synthesis and crystal structure of 1-ethyl-3-(phenyl)-1,2,3-triazolium percholorate

The isolation of stable carbenes of the Arduengo (1a) and Wanzlick (2a) type has prompted us to look for stable nitrenium ions of the related structural type 1-ethyl-3-(phenyl)-1,2,3-triazolium perchlorate (6⁺). The title compound C₁₀H₁₄Cl N₃O₄ was isolated and structure was investigated by X-ray crystallography. It crystallizes in the monoclinic space group P2₁/c with cell parameters a=6.697(4) Å, b=9.724(9) Å, c=19.844(2) Å and Z=4. The final residual factor is R1=0.0471 for 1545 reflections with I>2σ(I). The structure exhibits intermolecular hydrogen bonds.     

Structure and spectra of 1,3-dioxanes. microwave spectrum,structural parameters and <Emphasis Type="Italic">ab initio</Emphasis> calculations of 1,3-dioxane

Microwave spectra of the 1,3-dioxane molecule (C₄H₈O₂) with the main isotopic composition and four its isotopomers (¹³C(2)¹²C₃H₈ ¹⁶O₂, ¹³C(4)¹²C₃H₈ ¹⁶O₂, ¹³C(5)¹²C₃H₈ ¹⁶O₂, ¹⁸O(1)¹²C₄H₈ ¹⁶O) are investigated in a frequency range of 28–44 GHz. Rotational transitions of b-and c-types with 2 ≤ J ≤ 5 are identified. Rotational constants, quartic constants of centrifugal distortion, isotope-substituted r _s-and effective r ₀-structures of the molecule ring are determined. Experimental data are compared to the results of quantum chemical calculations of different levels.     

Sc(III), Eu(III), and Gd(III) Complexes with Macrocyclic Cavitand Cucurbit[6]uril: Synthesis and Crystal Structures

Slow evaporation of solutions of Sc and Eu nitrates with macrocyclic cavitand cucurbit[6]uril gives crystals of isostructural complexes [Sc(NO₃)(H₂O)₄(C₃₆H₃₆N₂₄O₁₂)](NO₃)₂ ? 8.5H₂O (space group Pna2₁, a = 32.0065(18) Å, b = 14.7904(8) Å, c = 11.5774(6) Å, V = 5480.6(5) ų, Z = 4) and [Eu(NO₃)(H₂O)₄(C₃₆H₃₆N₂₄O₁₂)](NO₃)₂ ? 6.75H₂O (space group Pna2₁, a = 31.9525(17) Å, b = 14.7203(8) Å, c = 11.8592(6) Å, V = 5578.0(5) ų, Z = 4). The metal to ligand ratio in these complexes is 1 : 1; the complexes are obtained at 0.025–0.1 mol/l concentrations of the metals in solutions. With higher lanthanide concentrations (0.7–1 mol/l), the 2 : 1 complex with cucurbit[6]uril is formed of the composition [{ Gd(NO₃)(H₂O)₅}₂(C₃₆H₃₆N₂₄O₁₂)](NO₃)₄ ? 6.5H₂O (space group \(P\bar 1\), a = 13.3972(6) Å, b = 14.4994(5) Å, c = 18.3290(8) Å, α = 73.5610(10)°, β = 87.2590(10)°, γ = 87.5540(10)°, V = 3409.4(2) ų, Z = 2) and isotypical complex [{Gd(NO₃)(H₂O)₅}₂{(C₅H₅N) ? (C₃₆H₃₆N₂₄O₁₂)}](NO₃)₄ ? 8H₂O with a pyridine molecule inside the cucurbit[6]uril cavity (space group P2₁/n, a = 14.8263(6) Å, b = 13.3688(7) Å, c = 18.5970(9) Å, β = 107.5860(10)°, V = 3513.8(3) ų, Z = 2). According to X-ray diffraction data, the metal atoms of the title complexes coordinate the O atoms in portals of cucurbit[6]uril molecules.     

<Emphasis Type="Italic">cis</Emphasis>-Dioxomolybdenum(VI) complexes of sterically encumbered phenol-based tetradentate N<Subscript>2</Subscript>O<Subscript>2</Subscript> ligands: Structural,spectroscopic, and electrochemical studies

Two cis-dioxomolybdenum(VI) complexes [MoO₂L] (L: L ¹, 2 and L: L ², 3) in a phenol-based sterically encumbered N₂O₂ ligand environment have been synthesized, and their crystallographic characterizations are reported. The orange crystals of 2 are monoclinic, space group P2₁/a with unit cell dimensions as a=16.2407(17) Å, b=7.2857(8) Å, c=18.400(2) Å, β=98.002(9)°, Z=4, and d _cal=1.486 g cm^?3. The light orange crystals of 3, however, are orthorhombic, space group, Pbcn, with unit cell dimensions a=8.3110(12) Å, b=12.637(3) Å, c=34.673(5) Å, Z=4, and d _cal=1.187 g cm^?3. The structures were refined by a full-matrix least-squares procedure on F ² to a final R=0.046 (0.055 for 3) using 4944 (3677) all independent data. In both the cases, the Mo atom exists in a distorted octahedral geometry defined by a N₂O₄ donor set, which features a cis-Mo(–O)₂ and a trans-Mo(OPh)₂ arrangement. Compound 2 undergoes a quasireversible one-electron reduction at ?1.3 V vs Ag/AgCl reference due to Mo^VIO₂/Mo^VO₂ electron transfer and thus providing a rare example of steric solution to the comproportionation–dimerization problem encountered frequently in the development of valid biomimetic models for the active sites of oxomolybdenum enzymes.     

Crystal structure of oxonium <Emphasis Type="Italic">trans</Emphasis>(O)-<Emphasis Type="Italic">cis</Emphasis>-(C)-dicyanobis(2-picolinato)cobaltate(III) hydrate: Two types of proton site

The trans(O)-cis(C)-bis(pyridine-2-carboxylato)dicyanocobaltate(III) ions, [Co(Pic)₂(CN)₂]^?, crystallize from acid medium with three water molecules per two crystallographically nonequivalent complexes whose charge is compensated by protons. One of the water molecules forms an oxonium ion (H₃O⁺) with a proton. The other two water molecules bound to each other through a short hydrogen bond O-H…O (2.403(2) Å) and thus forming (H₅O₂)⁺ cations is another proton site. The (H₃O)(H₅O₂)[Co(Pic)₂(CN)₂]₂ crystals are monoclinic: a = 10.7027(7) Å, b = 25.786(1) Å, c = 11.4865(8) Å, β = 91.411(9)°, Z = 4, space group P2₁/n.     

Supramolecular architecture of catechol and its 2:1 complex with dimethylsulfoxide

The crystal structures of catechol (o-dihydroxybenzene) and its 2:1 complex with dimethylsulfoxide are determined at T = 150 K. Crystal data: C₁₄H₁₈O₅S, M = 298.37, triclinic, space group P \(\bar 1\), unit cell parameters: a = 7.7285(13) Å, b = 9.9924(17) Å, c = 10.3188(18) Å, α = 89.963(4)°, β = 89.968(4)°, γ = 69.076(5)°, V = 744.3(2)ų, Z = 2, D _x = 1.331 g/cm³, R1 = 0.048; C₆H₆O₂, M = 110.11, monoclinic, space group P2₁/n, a = 9.8206(6)Å, b = 5.5903(3)Å, c = 10.4439(6)Å, β = 114.952(2)°; V = 519.85(5) ų, Z = 4, D _x = 1.407 g/cm³, R1 = 0.0289. In the 2:1 complex the molecules are joined in a supramolecular ensemble by D-H...A hydrogen bonds (D = O, C; A = O, π); in catechol they are bonded only by O-H...O. The state diagram of the catechol-dimethylsulfoxide system is examined by DTA.     

Synthesis and X-ray diffraction study of Li(H<Subscript>3</Subscript>O)[UO<Subscript>2</Subscript>(C<Subscript>2</Subscript>O<Subscript>4</Subscript>)<Subscript>2</Subscript>(H<Subscript>2</Subscript>O)] · H<Subscript>2</Subscript>O

Single crystals of Li(H₃O)[UO₂(C₂O₄)₂(H₂O)] · H₂O (I) have been synthesized and studied by X-ray diffraction. Compound I crystallizes in the monoclinic crystal system with the unit cell parameters: a = 7.1682(10) Å, b = 29.639(6) Å, c = 6.6770(12) Å, β= 112.3(7)°, space group P 2₁/c, Z = 4, R = 4.36%. Structure I contains discrete mononuclear groups [UO₂(C₂O₄)₂(H₂O)]^2? ascribed to the crystal-chemical group AB ₂ ⁰¹ M¹ (A = UO₂ ²⁺, B⁰¹ =C₂O ₄ ^2? , M¹ = H₂O), which are “cross-linked” by the lithium ions into infinite layers {Li(UO₂)(C₂O₄)₂(H₂O)₂}^? perpendicular to [010]. The hydroxonium ions are located between adjacent uranium-containing layers. A hydrogen bond system involving water molecules, oxalate ions, and hydroxonium combines the anionic layers into a three-dimensional framework.     

Thermal Rearrangements of 3<Emphasis Type="Italic">H</Emphasis>- and 4<Emphasis Type="Italic">H</Emphasis>-Pyrazoles Prepared by Reactions of 9-Diazofluoren with Methyl Tetrolate and Methyl 3-Phenylpropiolate

9-Diazofluoren adds in Et₂O at 20°C to methyltetrolate in keeping with Auwers rule and nonregioselectively adds to methyl-3-phenylpropiolate with the formation of spirocyclic 3H-pyrazoles. The methyltetrolate adduct at boiling in toluene converts into methyl 3a-methyl-3aH-dibenzo[e,g]indazole-3-carboxylate, at 190°C in benzene, into methyl 3-methyl-2H-dibenzo[e,g]indazole-2-carboxylate, and at 160°C in methanol, into 3-methyl-2H-dibenzo[e,g]indazole. Auwers adduct of methyl 3-phenylpropiolate at boiling in benzene gives cyclopropene derivative and at boiling in methanol isomerizes into methyl 3a-phenyl-3aHdibenzo[e,g]indazole-3-carboxylate. Anti-Auwers adduct at boiling in benzene isomerizes into methyl 2-phenylpyrazolo[1,5-f]phenanthridine-3-carboxylate.     

Crystal structures of a family of layered coordination polymers containing divalent metal ions (Mn<Superscript>2+</Superscript>, Co<Superscript>2+</Superscript>, Ni<Superscript>2+</Superscript> and Zn<Superscript>2+</Superscript>) and the 3-amino 4-methyl benzoate ion

The syntheses and crystal structures of the layered coordination polymers M(C₈H₈NO₂)₂ [M = Mn (1), Co (2), Ni (3) and Zn (4)] are described. These isostructural compounds contain centrosymmetric trans-MN₂O₄ octahedra as parts of infinite sheets; the ligand bonds to three adjacent metal ions in μ³-N,O,O′ mode from both its carboxylate O atoms and its amine N atom. In each case, weak intra-sheet N–H?O and C–H?O hydrogen bonds may help to consolidate the structure. Crystal data: 1, C₁₆H₁₆MnN₂O₄, M _r = 355.25, monoclinic, P2₁/c (No. 14), a = 10.6534(2) Å, b = 4.3990(1) Å, c = 15.5733(5) Å, β = 95.1827(10)°, V = 726.85(3) ų, Z = 2, R(F) = 0.026, wR(F ²) = 0.067. 2, C₁₆H₁₆CoN₂O₄, M _r = 359.24, monoclinic, P2₁/c (No. 14), a = 10.6131(10) Å, b = 4.3374(4) Å, c = 15.3556(17) Å, β = 95.473(4)°, V = 703.65(12) ų, Z = 2, R(F) = 0.041, wR(F ²) = 0.091. 3, C₁₆H₁₆N₂NiO₄, M _r = 359.02, monoclinic, P2₁/c (No. 14), a = 10.6374(4) Å, b = 4.2964(2) Å, c = 15.2827(8) Å, β = 95.9744(14)°, V = 694.66(6) ų, Z = 2, R(F) = 0.028, wR(F ²) = 0.070. 4, C₁₆H₁₆N₂O₄Zn, M _r = 365.68, monoclinic, P2₁/c (No. 14), a = 10.6385(5) Å, b = 4.2967(3) Å, c = 15.2844(8) Å, β = 95.941(3)°, V = 694.89(7) ų, Z = 2, R(F) = 0.038, wR(F ²) = 0.107.     

Crystal structure of 1-cyclohexylpiperazine-1,4-diium dichromate(VI)

Single crystals of 1-cyclohexylpiperazine-1,4-diium dichromate(VI), (C₁₀H₂₂N₂)[Cr₂O₇], were obtained by slow evaporation at room temperature from an aqueous solution of potassium dichromate, hydrochloric acid and 1-cyclohexylpiperazine. (C₁₀H₂₂N₂)[Cr₂O₇] is triclinic (P\(\bar 1\)) with a = 10.351(2) Å, b = 12.766(3) Å, c = 6.111(1) Å, α = 91.50(2)°, β = 104.26(3)°, γ = 94.91(2)°, V = 778.8(3) ų, and Z = 2. The structure determination performed from single crystal X-ray diffraction data leads to R₁/wR₂ reliability factors of 0.032/0.078. The asymmetric unit of the title salt C₁₀H₂₂N₂²⁺·Cr₂O₇^2?, consists of one 1-cyclohexylpiperazine-1,4-diium dication and one dichromate dianion. These entities are linked together by N–H···O hydrogen bonds to form {(C₁₀H₂₂N₂)[Cr₂O₇]}_n infinite chains lying parallel to the (100) plane and running along the c axis. The intermolecular N–H···O hydrogen bonds link these chains into a two-dimensional network structure consolidated through C–H···O weak interactions.     

Ruthenium(II,III,III) μ<Subscript>3</Subscript>-oxotrifluoroacetate with dimethyl sulfoxide: Synthesis,structure, and DTF quantum-chemical calculations

The reaction of [Ru ₃ ^III (μ₃-O)(μ-O₂CCF₃)₆(H₂O)₃](O₂CCF₃) in methanol gives two solvates, [Ru₃O(O₂CCF₃)₆(DMSO)₃] · 1/2H₂O (I) and [Ru₃O(O₂CCF₃)₆(DMSO)₃] · H₂O (II), of a novel trinuclear mixedvalence Ru(II,III,III) trifluoroacetate complex, where two DMSO molecules are coordinated to the Ru atoms through the O atom, while the third DMSO molecule is coordinated through the S atom. According to the X-ray diffraction data, the complex can crystallize in two crystal systems: triclinic (I) (space group P \(\overline 1 \)) and monoclinic (II) (space group P2₁/m). The unit cell parameters for I are: a = 9.354, b = 11.005, c = 20.846 Å, α = 99.10, β = 96.38, γ = 92.17, Z = 2; R = 7.27%; for I are: a = 9.186, b = 17.044, c = 13.091 Å, β = 101.10, Z = 2; R = 14.18%.     

Structure of Potassium and Cesium Barbiturates

The structures of catena-[K(μ₆-Hba?O,O,O,O′,O′,O″)] (I) and catena-[Cs(μ₆-Hba–O,O,O′,O′,O″,O″)] (II), where Н₂ba is barbituric acid C₄H₄N₂O₃, were characterized by powder X-ray diffraction. Crystallographic data: a = 14.1603 (4) Å, b = 3.68977 (9) Å, c = 10.9508 (3) Å, β = 82.226 (1)°, V = 566.90 (3) ų, space group P2₁/n, Z = 4 for I; a = 14.652 (1) Å, b = 11.7275 (7) Å, c = 3.8098 (3) Å, β = 79.140 (6)°, V = 642.90 (8) ų, space group C2/m, Z = 4 for II. The structural topologies of alkali metal complexes with barbituric acid and some its derivatives were compared. The thermal stability of complexes I and II in an air atmosphere was studied.     

Crystal structure of triethylammonium dicitratoborate monohydrate

Triethylammonium dicitratoborate monohydrate (C₂H₅)₃NH[(C₆H₆O₇)₂B]·H₂O (I) was synthesized for the first time. Its crystal structure was solved from single crystal X-ray diffraction data (a = 9.7821(2) Å, b = 23.2196(4) Å, c = 10.0705(2) Å; β = 90.97(1)°; Z = 4, space group P2₁/n, 5091 reflections with R _int = 0.0219; R1 = 0.0733). The structural units of crystal I (the large dicitrato borate anion with a spirane structure, the triethylammonium cation, and the crystal water molecule) form a layered packing with a system of seven O-H...O and N-H...O hydrogen bonds.     

Synthesis,crystal structure,and kinetics of thermal decomposition of the Zn(II) complex with vanillin

A complex [Zn(C₈H₇O₃)₂(H₂O)₂] (C₈H₈O₃ is vanillin) has been synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. The crystals are monoclinic, space group C2/c, a = 22.236(8) Å, b = 10.594(2) Å, c = 7.8190(16) Å, α = 89.90(3)°, β = 106.87(4)°, γ = 89.99(3)°, V = 1762.6(8) ų, Z = 4, F(000) = 832, S = 1.079, ρ _c = 1.521g cm^?3, R = 0.0221, R _w = 0.0604, μ = 1.433 mm^?1. The Zn²⁺ ion is six-coordinated with a distorted octahedron geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds. The thermal decomposition kinetics of the complex for the second stage was studied under non-isothermal conditions by the TG and DTG methods. The kinetic equation can be expressed as dα/dt = Ae^?E/RT 2(1 ? α)[1 ? ln(1 ? α)]^1/2. The kinetic parameters (E, A), activation entropy ΔS ^≠, and activation free-energy ΔG ^≠ were also gained.     

Two New One-Dimensional Chain-Like Compounds Constructed from the Sandwich-Type Polyoxotungstate Clusters

Two new one-dimensional chain-like compounds, K₄Na₄[Mn₂(H₂O)₈Mn₄(H₂O)₂(GeW₉O₃₄)₂] · 20.5H₂O (1) and K₂Na₄Cu₂(H₂O)₁₂[Cu(H₂O)₂Cu₄(H₂O)₂(SiW₉O₃₄)₂] · 15H₂O (2), constructed from the sandwich-type clusters, have been obtained by the routine synthetic reactions in aqueous solutions, and their structures were determined by X-ray single crystal diffraction analysis. The crystal data is following: for 1, space group, monoclinic, P _21/n, a = 16.693(3) Å, b = 14.935(3) Å, c = 20.090(4) Å, β = 92.23(3)°, V = 5004.7(17) ų, Z = 2; For 2, space group, triclinic, P _?1, a = 11.744(2) Å, b = 13.415(3) Å, c = 17.609(4) Å, α = 73.08(3)°, β = 82.68(3)°, γ = 65.18(3)°, V = 2409.1(8) ų, Z = 1. The crystal structure of 1 shows a 1D ladder-like chain, built up of the sandwich anions [Mn₄(H₂O)₂(GeW₉O₃₄)₂]^12? and the Mn²⁺ ions. Compound 2 is a polymeric chain, composed of the Cu-substituted sandwich-type anions [Cu₄(H₂O)₂(SiW₉O₃₄)₂]^12? linked by the Cu(H₂O)₄ clusters. These extended materials based on the sandwich-type polyoxoanions are rarely reported in the POM chemistry.     

Crystal and molecular structure of <Emphasis Type="Italic">tris</Emphasis>(<Emphasis Type="Italic">m</Emphasis>-chlorophenyl)phosphine selenide

The crystal and molecular structure of tris(m-chlorophenyl)phosphine selenide, C₁₈H₁₂Cl₃PSe (I), was investigated by X-ray diffraction (XRD) analysis. The trigonal rhombohedral structure of I (space group \(R\overline 3 c\), a = 14.110(2) Å, c = 32.360(4) Å, Z = 12) was solved by direct methods and refined by least squares in an anisotropic approximation (R = 0.029) for 1319 averaged measured reflections (CAD-4 automatic diffractometer, λCuK_α).     

Formation of the high-pressure modification of hydrated talc at 450°C and 4 GPa: <Emphasis Type="Italic">In situ</Emphasis> diffraction study

The formation of the high-pressure hydrous phase Mg₃Si₄O₁₀(OH)₂?xH₂O (10 Å phase) through the reaction “talc + water” at 450°C and 4 GPa was studied using diamond anvil cell. The powder diffraction measurements in situ, performed at the Siberian Center of Synchrotron and Terahertz Radiation (SSTRC), were applied to refine the lattice parameters, atomic coordinates and the occupancy of interlayer H₂O site in the structure of 10 Å phase at 450°C and 4 GPa. The lattice parameters are a = 5.234(1) Å, b = 9.053(2) Å, c = 10.87(1) Å, β = 99.2(1)°, and V = 508.5(6) ų (space group C2/m). The results of Rietveld refinement show the best fit for the trioctahedral mica structure with split position Ow of the interlayer H₂O molecule. The half occupancy of the Ow site corresponds to one H₂O molecule per formula unit.     

Crystal structure of Mg pivalate hydrate Mg(H<Subscript>2</Subscript>O)<Subscript>6</Subscript>(Piv)<Subscript>2</Subscript> · 3H<Subscript>2</Subscript>O

Single crystals of Mg pivalate hydrate, Mg(H₂O)₆(Piv)₂ · 3H₂O (HPiv = (CH₃)₃CCOOH) are synthesized and their structure is determined by X-ray diffraction method. The crystals are rhombic: a = 10.917(2) Å, b = 12.625(2) Å, c = 31.394(8) Å, Z = 8, space group Pbca, R ₁ = 0.0525. The Mg atom has octahedral surrounding of the O atoms of water molecules (Mg-O 2.044–2.137 Å). The cationic chains of [Mg(H₂O)₆] _∞ ²⁺ lie in the voids of doubled network anionic layers of [(H₂O)₃(Piv)₂] _∞∞ ^2? . Inside the layer, the pivalate anions alternate with water molecules in the xy plane, being bonded to them by hydrogen bonds. The cationic chains and the anionic layers are united into layered packs by hydrogen bonds between coordinated water molecules and pivalate anions and between coordinated and crystal hydrate water molecules.     

Syntheses and characterization of two 1D Cu(II) coordination polymers with 2,2′:6′,2″-terpyridine ligand

The solution reactions of CuCl₂ with 2,2′:6′,2″-terpyridine (Terpy) and dicarboxylic acid (glutaric acid or suberic acid) afforded two 1D coordination polymers [Cu(Terpy)(C₅H₆O₄)] _n (I) and [Cu(Terpy)(C₈H₁₂O₄)] · 3H₂O (II) and their structures were characterized by IR, TG-DTA, and single-crystal X-ray diffraction. Crystallographic data for I: C₂₀H₁₆CuN₃O₄, M _r = 425.90, monoclinic, space group C2/c, a = 10.335(2), b = 21.193(4), c = 8.580(2) Å, β = 111.99(3)°, V = 1742.5(6) ų, Z = 4, ρ _c = 1.623 g/cm³, F(000) = 872, R = 0.0304 and wR = 0.0915; and those for II: C₂₃H₂₉CuN₃O₇, M _r = 523.03, triclinic, space group P \(\bar 1\), a = 8.362(2), b = 10.605(2), c = 14.617(3) Å, α = 73.26(3)°, β = 86.23(3)°, γ = 69.45(3)°, V = 1161.3(4) ų, Z = 2, ρ _c = 1.496 g/cm³, F(000) = 546, R = 0.0636 and wR = 0.1106. X-ray diffracion studies reveal that both complexes I and II feature 1D chain. The 1D polymer chains are connected by π-π-stacking interactions to generate 2D supramolecular layers.