Synthesis of <Emphasis Type="Italic">E</Emphasis> Isomer and Crystal Structures of <Emphasis Type="Italic">E</Emphasis> and <Emphasis Type="Italic">Z</Emphasis> Isomers of 3-(2,5-Dimethoxyphenyl)-2-(4-methoxyphenyl)acrylonitrile

Abstract Details of the synthesis of the E isomer of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylonitrile, and the X-ray crystal structures of both the E and Z isomers of this compound are presented. The E isomer crystallizes in the P2₁/c space group with cell parameters, a = 8.5659(17) ?, b = 16.399(3) ?, c = 11.224(2) ?, α = 90°, β = 95.27(3)°, γ = 90°and Z = 4. The Z isomer crystallizes in the Pca2₁ space group with cell parameters, a = 4.1223(8) ?, b = 19.113(4) ?, c = 19.453(4) ?, α = 90°, β = 90°, γ = 90° and Z = 4. Index Abstract Synthesis of E isomer and X-ray crystal structure determination of both E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylonitrile are presented.      

Structural Studies of the 1:1 Complex of <Emphasis Type="Italic">o</Emphasis>-3,4-Dimethyltetrathiafulvalene (<Emphasis Type="Italic">o</Emphasis>-Me<Subscript>2</Subscript>TTF) and 1,2,4,5-Tetracyanobenzene (TCNB)

Abstract  

The synthesis and crystal structure of the 1:1 complex o-Me₂TTF-TCNB is reported. The complex crystallizes in the triclinic space group P-1 with a = 6.920(1) ?, b = 7.928(2) ?, c = 17.453(4) ?, α = 100.53(3)°, β = 99.66(3)°, and γ = 97.32(3)°. The bond length of the central C=C bond in o-Me₂TTF is 1.342(2) ?, indicating a neutral state for the o-Me₂TTF donor.     

Synthesis,Separation and Crystal Structures of <Emphasis Type="Italic">E</Emphasis> and <Emphasis Type="Italic">Z</Emphasis> Isomers of 3-(2,5-Dimethoxyphenyl)-2-(4-Methoxyphenyl)Acrylic Acid

Abstract Synthesis, separation and X-ray crystal structures of E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylic acid are reported. Separation of E and Z isomers from a 1:1 mixture has been carried out by selective acidification of their sodium salts carefully controlling the pH of the solution. The structures of E and Z isomers were confirmed by determining crystal structures of these isomers using single crystal X-ray diffraction. The E isomer crystallizes in the P2₁/c space group with a = 11.493(2) ?, b = 5.5456(11) ?, c = 24.900(5) ?, α = 90°, β = 92.36(3)°, γ = 90°, Z = 4. The Z isomer crystallizes in the P2₁/c space group with a = 10.192(2) ?, b = 12.893(3) ?, c = 13.948(3) ?, α = 90°, β = 92.18(3)°, γ = 90°, Z = 4. Details of the synthesis and structural characterization and X-ray crystal structure determination of the title compounds are presented. Index Abstract Synthesis, Separation and Crystal Structures of E and Z Isomers of 3-(2,5-Dimethoxyphenyl)-2-(4-Methoxyphenyl)Acrylic Acid Balachandra Chenna, Bidhan A. Shinkre, Shweta Patel, Samuel B. Owens Jr., Gary M. Gray, Sadanandan E. Velu* Separation of E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylic acid from a 1:1 mixture has been carried out by selective acidification of their sodium salts and the structures of the individual isomers have been determined by X-ray single crystal diffraction.      

Crystal structure of 1,7-dihydroxyxanthone from <Emphasis Type="Italic">Weddellina squamulosa</Emphasis> Tul

1,7-dihydroxyxanthone was isolated from Weddellina squamulosa Tul. (Podostemaceae) and the crystal structure has been determined (C₁₃H₈O₄), Mr = 228.19, a = 4.902(1), b = 13.593(4), c = 14.740(2) Å, space group P2₁2₁2₁, Z = 4, and V = 982.2(4) ų. The 1,7-dihydroxyxanthone molecule is planar with a strong intramolecular H-bond O–HsO [2.607(4) Å]. The molecular packing is done through hydrogen bonds O–HsO [2.786(4) Å], forming channels along the direction parallel to the a-axis.     

Structure of Triammonium <Emphasis Type="Italic">fac</Emphasis>-Trichloridotrioxidorhenate(VII) Chloride with <Emphasis Type="Italic">C</Emphasis><Subscript>3<Emphasis Type="Italic">v</Emphasis></Subscript> Crystallographic Symmetry of the Complex Anion

Abstract  

The unstable crystals of triammonium fac-trichloridotrioxidorhenate(VII) chloride have been obtained from ammonium rhenate(VII) solution in concentrated hydrochloric acid. The crystal structure consists of fac-trichloridotrioxidorhenate(VII) anions, chloride anions and ammonium cations. Each fac-trichloridotrioxidorhenate(VII) anion and each chloride anion lies in special position of 3m site symmetry (cell parameters: a = 9.026(3) Å; c = 7.690(4) Å; space group: P6₃ mc). The ammonium cation lies in special position of m site symmetry. The following anion geometrical parameters of the fac-trichloridotrioxidorhenate(VII) anion have been obtained: Re–O bond length of 1.720(2) Å, Re–Cl bond length of 2.5428(9) Å, the bond angles: O–Re–O of 103.5(1)° and Cl–Re–Cl of 79.8(1)°.     

Solid-state structure of a 1:1 adduct of 2-<Emphasis Type="Italic">t</Emphasis>-butylphenol and 3-<Emphasis Type="Italic">t</Emphasis>-butylsalicylaldehyde

The co-crystal structure of 2-t-butylphenol with 3-t-butylsalicylaldehyde (1) was obtained by single-crystal X-ray diffraction. 2-t-Butylphenol was co-crystallized with 1 equivalent of 3-t-butylsalicylaldehyde. The phase crystallizes in the monoclinic system with P2₁/c space group. The unit cell dimensions are a = 12.351(3) Å, b = 15.253(3) Å, c = 10.377(2) Å, β = 97.58(3)^∘, V = 1937.8(7) ų and Z = 4. The structure of the crystal layered by nonpolar group includes strong intramolecular and weak intermolecular hydrogen bonds. The aldehyde oxygen O2 accepts a three-centered bond through intramolecular O1–H1A⋅sO2 and intermolecular O3–H3A⋅sO2 interactions. In addition, the crystal consists of right-handed helical (P) and left-handed helical (M) chains linked by hydrogen bonding.     

The Crystal Structure of <Emphasis Type="SmallCaps">dl</Emphasis>-Lomenfloxacin Hydrate

Abstract  The dl-lomenfloxacin hydrate is an innersalt, which crystallizes in space group C2/c with cell parameters a = 22.897(10), b = 8.682(1), c = 18.365(2) ?, β = 93.633(9)°, V = 3,705(3) ?³ and Z = 8. The piperazinyl ring adopts a chair conformation, and the quinolone ring is essentially planar. The plane defined by C atoms of the piperazinyl ring is not coplanar with the quinolone ring. The carboxylate group shows two disorder parts, and is not coplanar with the quinolone ring, the dihedral angle between them is 113.8°. The disorder carboxylate group is split into two parts, the planes of which are skewed at the dihedral angles of 24.5 and 21.6° with the plane of the quinolone ring, respectively. The IR of the title compound is measured and studied. Index abstract  The crystal structure of dl-lomenfloxacin hydrate is determined by X-ray diffraction. The IR is measured and shows great differences from previous studies.      

Crystal Structure of Two <Emphasis Type="Italic">V</Emphasis>-shaped Ligands with <Emphasis Type="Italic">N</Emphasis>-Heterocycles

Two V-shaped ligands with N-heterocycles, bis(4-(1H-imidazol-1-yl) phenyl)methanone (1), and bis(4-(1H-benzo[d]imidazol-1-yl)phenyl)methanone (2) have been synthesized and characterized by elemental analyses, IR and 1H NMR spectroscopy. Crystal structures of 1 and 2 have been determined by X-ray diffraction. The crystal of 1 is monoclinic, sp. gr. P2₁/c, Z = 4. The crystal of 2 is orthorhombic, sp. gr. Fdd2, Z = 8. X-ray diffraction analyses show that the V-shaped angles of 1 and 2 are 122.72(15)° and 120.7(4)°, respectively. Intermolecular C–H···O, C–H···N, C–H···π, and π···π interactions link the components into three-dimensional networks in the crystal structures.     

The Synthesis and Structure of Two Novel <Emphasis Type="Italic">N</Emphasis>-(Benzothiazol-2-yl)benzamides

Abstract  Two novel benzothiazoles 2-chloro-N-(benzothiazol-2-yl)benzamide (1) and 2-chloro-N-(6-cyanobenzothiazol-2-yl)benzamide (2) were obtained in multistep synthesis. They were characterised by means of IR, ¹H- and ¹³C-NMR spectroscopy and also by single-crystal X-ray diffraction. The compound 1 crystallises with triclinic space group P , a = 9.5923(8) ?, b = 9.8583(8) ?, c = 13.8962(10) ?, α = 89.162(6)°, β = 77.741(7)°, γ = 80.064(7)°, V = 1264.5(2) ?³, Z = 4 and compound 2 crystallises as methanol solvate with monoclinic space group P 2₁/n, a = 7.5093(9) ?, b = 13.0211(14) ?, c = 16.032(2) ?, β = 92.717(10)°, V = 1565.9(3) ?³, Z = 4. Both crystal structures consist of discrete dimers connected into a three-dimensional network by intermolecular C–H···O and C–H···X (X = Cl or S) hydrogen bonds and by face-to-face π–π stacking interactions. Index Abstract  The synthesis and structure of two novel N-(benzothiazol-2-yl)benzamides. Irena Ćaleta, Dominik Cinčić, GraceKarminski-Zamola and Branko Kaitner. Hydrogen bonds and π–π interactions in N-(benzothiazol-2-yl)benzamides N-(benzothiazol-2-yl)benzamides.      

Synthesis,Crystal Structure and Spectroscopy of <Emphasis Type="Italic">catena-</Emphasis>poly-bis(azido-<Emphasis Type="Italic">N1,N1</Emphasis>)(2-Aminopyrimidine)Copper(II)

Abstract The compound [Cu(ampym)(μ_1,1-N₃)₂]_n (ampym = 2-aminopyrimidine) has been synthesized and characterized by X-ray crystallography and infrared spectroscopy. In addition, Ligand Field and powder EPR measurements have been performed. The structure is solved in space group P21/c with a = 7.303(2), b = 19.716(4), c = 5.949(1) ?, β = 98.17(3), V = 847.9(3) ?³, Z = 2 with final R = 0.0382. The coordination geometry around the Cu(II) ion is distorted square pyramidal, with four nitrogen atoms of four bridging azido anions in the basal plane with Cu–N distances that range from 1.998(3) to 2.069(3) ?. The apical position is occupied by a nitrogen atom of the ampym molecule at a Cu–N distance of 2.169(3) ?. The trans-basal angles are 165.7(1) and 143.9(1)°. Weak hydrogen bonding is observed between the two amine hydrogen atoms and nitrogen of an azide anion and the pyrimidine-ring nitrogen atom of a neighbouring molecule (N···N distances 3.174(5), 3.106(4) ?). These last hydrogen bonds (N7···N3) are forming so-called “Watson-Crick type” hydrogen bonds. In the infrared the vibrations of the coordinated azide anion are observed at 2,062, 1,273 and 655 cm⁻¹, while the Cu–N vibrations are observed at 370 and 224 cm⁻¹. Ligand-field and EPR spectra are uneventful and give spectral parameters expected in the range for such Cu(II) compounds. Magnetic susceptibility measurements reveal a weak antiferromagnetic interaction between the Cu(II) ions. Index Abstract A new Cu(II) compound, [Cu(2-aminopyrimidine)(μ_1,1-N₃)₂]_n has been synthesized and characterized by X-ray crystallography and by IR, Ligand Field, EPR spectroscopy and magnetic susceptibility. The coordination geometry around the Cu(II) ion is distorted square pyramidal, with four nitrogen atoms of four bridging azido ligands in the basal plane with Cu–N distances that range from 1.998(3) to 2.069(3) ?. The apical position is occupied by a nitrogen atom of the ampym molecule at a Cu–N distance of 2.169(3) ?. Also a very interesting hydrogen bond system occurs between pairs of ligands in the lattice. .     

Crystal Structure of [Zn(2-Bromobenzoato)<Subscript>2</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> and [Zn(2-Bromobenzoato)<Subscript>2</Subscript>(<Emphasis Type="Italic">N</Emphasis>-Methylnicotinamide)]<Subscript>2</Subscript>

Abstract  

The syntheses and structural characterizations of two novel 2-bromobenzoatozinc(II) complexes—[Zn(2-BrC₆H₄COO)₂] _n (I) and [Zn(2-BrC₆H₄COO)₂(mnad)]₂ (II), where mnad is N-methylnicotinamide are reported. Compound (I) crystallized with a monoclinic lattice (space group P2₁/c) and is polymeric in solid state. Its cell parameters are: a = 7.37220(10) Å, b = 19.9639(3) Å, c = 30.2756(5) Å, β = 94.7510(7)°, V = 4440.59(12) ų, Z = 4. The coordination environments of all zinc atoms are distorted tetrahedra built from four carboxylate oxygen atoms coming from four 2-bromobenzoato ligands. Compound (II) crystallized with a monoclinic lattice (space group P2₁/c) with a = 11.7488(2) Å, b = 20.3683(3) Å, c = 9.30130(10) Å, β = 100.3941(11)°, V = 2189.30(5) ų, Z = 2. This dimeric molecule features a paddle-wheel [Zn₂O₈] cage in solid state; the coordination environment of the central atom is square pyramidal consisting of four carboxylate oxygen atoms and the pyridine N atom of the mnad ligand.     

X-ray analysis of sideroxol from <Emphasis Type="Italic">Sideritis leptoclada</Emphasis>

Sideroxol (1), a kaurane diterpene which has the ent-7α,18-dihydroxy-15β,16β-epoxykaurane structure (MW = 320.47, C₂₀H₃₂O₃) was obtained from the acetone extract of Sideritis leptoclada plant as well as from some other Sideritis species. It crystallizes in the orthorhombic space group P2₁, 2₁, 2₁ with a = 10.967(3), b = 24.555(5), c = 6.372(4) Å, Dc = 1.240 g cm⁻³, Z = 4, and refines to R = 0.065 for 721 independent reflections. The skeleton consists of three fused six-membered rings and a five-membered ring with fused epoxide. The six membered rings exhibited slightly distorted chair conformation. In addition to sideroxol, two kaurane and five kaurene diterpenes were isolated from the hexane and acetone extracts of the studied plant.     

Synthesis and Crystal Structures of <Emphasis Type="Italic">o</Emphasis>-[(Phenyl/<Emphasis Type="Italic">p</Emphasis>-methoxyphenyl)carbamoyl]benzene Sulfonamides

Abstract  

o-[(Phenyl/p-methoxyphenyl)carbamoyl]benzene sulfonamides were synthesized in a straightforward manner utilizing directly saccharin and aniline/p-anisidine as starting material and their crystal structures have been determined. (C₁₃H₁₂N₂O₃S): Mr = 276.31, monoclinic, P2₁/c, a = 10.277(6), b = 7.501(2), c = 16.261(10) ?, β = 96.37(2)°, V = 1,245.8(11) ?³, Z = 4. (C₁₄ H₁₄ N₂ O₄ S): Mr = 306.33, monoclinic, P2₁/c, a = 10.381(5), b = 7.861(2), c = 16.837(9) ?, β = 93.43(2)°, V = 1,371.5(10) ?³, Z = 4. In both structures the phenyl rings are inclined at 47.09(7) and 39.88(5)° with respect to each other and the structures are characterized by extensive inter and intramolecular hydrogen bonds.     

The Synthesis and Crystal Structure of 5-(4-Bromophenylamino)-2-methylsulfanylmethyl-2<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazol-4-carboxylic Acid Ethyl Ester

Abstract  The 5-(4-bromophenylamino)-2-methylsulfanylmethyl-2H-1,2,3-triazol-4-carboxylic acid ethyl ester 6 was synthesized from p-bromoaniline. The yielded product 6 was investigated with X-ray crystallographic, NMR, MS, and IR techniques. Compound 6, C₁₃H₁₅BrN₄O₂S, Mr = 371.26, crystallizes in the monoclinic space group P2₁/n with unit cell parameters a = 5.5220(1), b = 26.996(5), c = 10.596(2) ?, β = 103.83(3). V = 1533.8(5) ?³, Z = 4, Dx = 1.608 mg m⁻³. The final R ₁ was 0.0844; wR ₂ was 0.1560. H-bond is discussed. Index Abstract  The structure of 5-(4-bromophenylamino)-2-methylsulfanylmethyl-2H-1,2,3-triazol-4-carboxylic acid ethyl ester from 5-amino-1-(4-bromophenyl)-1,2,3-triazol-4-carboxylic acid ethyl ester is studied. H-bond is discussed.      

Synthesis and structural studies of <Emphasis Type="Italic">tris</Emphasis>-2-chlorobenzylamine and <Emphasis Type="Italic">tris</Emphasis>-2-bromobenzylamine

The tris-2-chloro and 2-bromotribenzylamines are prepared from aqueous ammonia and 2-chlorobenzyl chloride and 2-bromobenzyl bromide, respectively, in ethanol. Recrystallization yielded colorless cubes of each product. The crystal structures are each solved in space group P , and are isostructural. The tris-2-chloro compound, 1, has a = 7.4226(5) Å, b = 9.0825(7) Å, c = 14.529(1) Å, = 78.279(1), = 82.389(1), = 84.661(1), and V = 948.41(12) ų with Z = 2, and d_calc = 1.368 Mg/m³. The tris-2-bromo analog, 2, has a = 7.6569(11) Å, b = 9.0922(13) Å, c = 14.614(2) Å, = 79.286(2), = 81.777(2), = 85.401(2), and V = 987.9(2) ų with Z = 2, and d_calc = 1.762 Mg/m³. Lithium–halogen exchange experiments conducted in tetrahydrofuran at –78C using n-butyl lithium revealed that no exchange occurred for the tris-2-chloro compound, but did occur for the tris-2-bromo analog to yield tribenzylamine upon quench and work-up.     

Synthesis and structure of 7-methyl-5-phenyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazolo[4,3-<Emphasis Type="Italic">e</Emphasis>]tetrazolo[4,5-<Emphasis Type="Italic">b</Emphasis>][1,2,4]triazine<Superscript>(1)</Superscript>

The synthesis of 5-azido-3-methyl-1-phenyl-1H-pyrazolo[4,3-e][1,2,4]triazine 2 and 7-methyl-5-phenyl-1H-pyrazolo[4,3-e]tetrazolo[4,5-b][1,2,4]triazine 3 is described and the crystal and molecular structure of the latter is reported. This compound crystallizes in the monoclinic system, space group P2₁/n, with cell constants a = 11.607(2) Å, b = 7.982(1) Å, c = 13.147(2) Å, = 110.60(1), Z = 4, T = 293 K and D_cal = 1.470 g cm^–3. The structure was solved by direct methods and refined to R value of 0.0368 for 1906 reflections. The X-ray analysis revealed that the linear form of the tetrazolo-fused ring system of 3 exists in the crystal. The molecule as a whole has an almost planar conformation stabilized by the short intramolecular NsH interaction. The molecular packing in the crystal is determined by the van der Waals forces only.Part 26 in 1,2,4-triazines in organic synthesis. For part 25 see Mojzych et al.¹     

Crystal Structure and Conformational Analysis of 4-[(<Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethylamino)Benzylidene]-2-Phenyloxazole-5-One

Abstract  

Molecular and crystal structure of 4-[(p-N,N-dimethylamino)benzylidene]-2-phenyloxazol-5-one, C₁₈H₁₆N₂O₂, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 12.1704(23) ?, b = 3.9810(5) ?, c = 30.9603(56) ?, β = 101.176(15)°, Z = 4, D _x = 1.32 g/cm³, μ(Mo Kα) = 0.087 mm⁻¹, and space group is P12₁/c1. The structure was solved by direct methods and refined to a final R = 0.047 for 3166 reflections with I > 2σ(I). The crystal structure is stabilized by C–H⋯O and C–H⋯N type intra-molecular, C–H⋯O type inter-molecular interactions. To enlighten the flexibility and the geometric isomerism (E or Z) of the title compound, the selected torsion angle is varied from −180 to 180° in every 10° separately and molecular energy profile is calculated and analyzed.     

Synthesis and structure of oxovanadium(IV) complexes [VO(<Emphasis Type="Italic">Acac</Emphasis>)<Subscript>2</Subscript>] and [VO(<Emphasis Type="Italic">Sal</Emphasis>: <Emphasis Type="Italic">L</Emphasis>-alanine)(H<Subscript>2</Subscript>O)]

Bis(acetylacetonato)oxovanadium C₁₀H₁₄O₅V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C₁₀H₉NO₅V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P2₁. The structures of compounds I and II are solved by direct methods and refined to R₁ = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.     

Synthesis,Characterization and Crystal Structure of Iridium(III)bis(2-<Emphasis Type="Italic">p</Emphasis>-tolyl-benzothiazolato-N,C<Superscript>2</Superscript>)(acetylacetonate)

Abstract  A novel thiazole-based iridium (III) complex (iridium(III)bis(2-p-tolyl-benzothiazolato-N,C²)(acetylacetonate)) has been prepared and fully characterized by EA, IR, ¹H-NMR and MS. The molecular structure of the complex has been determined by single crystal X-ray diffraction analysis. The iridium (III) center adopts a distorted octahedral geometry with cis-O–O, cis-C–C, and trans-N–N chelate disposition. The complex crystallizes in the orthorhombic Pbca space group with cell parameters a = 10.1388(7) ?, b = 18.3565(12) ?, c = 31.021(2) ?, α = β = γ = 90 ° and Z = 8. The electronic absorption and emission spectra of this complex have been investigated. Index Abstract  A novel thiazole-based phosphorescent iridium (III) complex (iridium(III) bis (2-p-tolyl-benzothiazolato-N,C²)(acetylacetonate)) has been prepared and fully characterized by EA, IR, ¹H-NMR, MS and X-ray diffraction analysis.     

A New <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethyl Purine from an Australian <Emphasis Type="Italic">Dictyoceratid Sponge</Emphasis>

Abstract  

N6-methyl mucronatine (C₈H₁₂N₅O) has been isolated from a dictyoceratid sponge collected in South East Queensland. The solid state structure of the new metabolite (I) was confirmed by X-ray crystallography, while an NMR study in d ₄-MeOH reveals the presence of a minor tautomer identified as (II).