Dichloro-{bis(Pyrazol-1-yl)}Palladium(II) Complexes: Structures of a DMSO Solvated Dichloro-{bis(3,5-Dimethylpyrazol-1-yl)Acetic Acid}Palladium(II) and Dichloro-{bis(3,5-Ditertbutylpyrazol-1-yl)Methane}Palladium(II)

Abstract  Two new palladium(II) complexes, dichloro-{bis(3,5-dimethylpyrazol-1-yl)acetic acid}palladium(II)PdCl₂(3,5-Me₂bpza)], (1) (3,5-Me₂bpza = 3,5-dimethylpyrazol-1-yl)acetic acid) and dichloro-{bis(3,5-ditertbutylpyrazol-1-yl)acetic acid}palladium(II), [PdCl₂(3,5-^tBu₂bpza)], (2a) [3,5- ^t Bu₂bpza = 3,5-ditertiarybutylpyrazol-1-yl)acetic acid] complexes, were synthesized from the reactions of pyrazol-1-yl ligands with palladium salts. Attempts to crystallize 2a led to a hydrolyzed product, dichloro-{3,5-ditertbutylpyrazol-1-yl}palladium(II) (2b), in which the acetic acid moiety in the ligand backbone of 1 is lost. Both complexes 1 and 2b have been characterized by single-crystal X-ray crystallography. Both complexes crystallized in triclinic system (P − 1 space group). The cell parameters are: complex 1 (a = 8.7960(14) Å, b = 16.238(2) Å, c = 16.430(2) Å, α = 78.038(10)°, β = 77.817(11)°, γ = 89.970(10)°) and complex 2b (a = 10.1492(2) Å, b = 12.4001(2) Å, c = 13.108(3) Å, α = 103.0690(10)°, β = 97.4120(10)°, γ = 107.2450(10)°). The asymmetric unit of 1 contains two crystallographic independent monomeric units of 1 and three molecules of DMSO solvent, whilst that of 2b has got one monomeric unit with one molecule of chloroform solvent. Index Abstract  Two palladium complexes, dichloro-{bis(3,5-dimethylpyrazol-1-yl)acetic acid}palladium(II), PdCl₂(3,5-Me₂bpza)], (1) (3,5-Me₂bpza = 3,5-dimethylpyrazol-1-yl)acetic acid) and dichloro-{bis(3,5-ditertbutylpyrazol-1-yl)acetic acid}palladium(II), [PdCl₂(3,5- ^t Bu₂bpza)], (3,5- ^t Bu₂bpza = 3,5-ditertiarybutylpyrazol-1-yl)acetic acid) complexes, were synthesized from the reactions of pyrazol-1-yl ligands with palladium salts. Attempt to obtain crystals of tertiarybutylpyrazolyl analogue led to hydrolysis, the crystal structure of the hydrolysis product was established by single crystal X-ray crystallography.      

Synthesis and Structural Characterization of Bis[(cyclohexylamino)pent-2-en-4-onato]-Chromium(II)

Abstract  Addition of one equivalent of CrI₂ to two equivalents of lithium cyclohexylamino-pent-2-en-4-onate results in bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II). Crystallization in diethylether reaction solvent forms the hemi-etherate A with the asymmetric unit showing two target compounds and one molecule of cocrystallized diethylether in the P-1 space group with crystal cell parameters a = 12.931(4) Å, b = 13.207(4) Å, c = 16.104(5) Å, α = 66.559(5)°, β = 77.670(5)°, γ = 81.562(5)°, V = 2,459.1(14) Å³ and Z = 4. Drying A in vacuo and recrystallization in pentane yields a nonsolvated crystalline phase B with an asymmetric unit displaying only one molecule of the target compound in the P2₁/c space group with crystal cell parameters a = 14.290(7) Å, b = 14.082(7) Å, c = 11.246(6) Å, β = 94.807(8)°, V = 2,255.1(19) Å³ and Z = 4. Graphical Abstract  A Cr(II) complex supported by two β-enaminoketiminato ligands, bis[(cyclohexylamino)pent-2-en-4-onato]-chromium(II), has been synthesized and has been structurally characterized in two different crystal phases.      

Synthesis,Crystal Structures and Magnetic Properties of Two Three-Dimensional Cerium(III) and Erbium(III) Coordination Polymers

Abstract  

Two lanthanide(III) coordination polymers, namely [Ce(pzdc)_1.5(H₂O)] _n (1), [Er(pzdc)(μ₂-OH)(H₂O)] _n ·nH₂O (2) (H₂pzdc = pyrazine-2,5-dicarboxylic acid), have been hydrothermally synthesized and characterized by single crystal X-ray diffraction and magnetic measurements. Polymer 1 crystallizes in triclinic space group P-1, with a = 6.2875(6), b = 6.7396(6), c = 13.3858(14) Å, α = 82.858(4), β = 83.118(4), γ = 63.452(4)°, V = 502.16(8) Å³, and Z = 2. Polymer 2 crystallizes in monoclinic space group P2(1)/c, with a = 11.706(4), b = 6.151(2), c = 14.063(5) Å, β = 92.255(3), V = 502.16(8) Å³, and Z = 4. Single-crystal X-ray diffraction studies show that compound 1 possess a 3D framework structure consisted of double chains. Compound 2 features a 3D open framework structure with a dinuclear Er(III) secondary building unit. Magnetic studies for complex 1 show stronger antiferromagnetic coupling between the Ce(III) ions.     

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.     

Absolute Configuration of Two Eudesmane Derivatives from <Emphasis Type="Italic">Verbesina turbacensis</Emphasis> H.B.K.

Abstract  

Two compounds isolated from the aerial parts of Verbesina turbacensis H.B.K, are reported in this work. Both compounds crystallize in the orthorhombic system, space group P2₁2₁2₁. Compound (1), 6β-[cinnamoyloxy]-3β,4α-dihydroxyeudesmane, formula C₂₄H₃₄O_4, has unit cell parameters a = 9.6234(2), b = 12.3137(3) and c = 18.6277(5) Å, V = 2207.38(9) Å³, Z = 4. On the other hand, 6β-[cinnamoyloxy]-eudesman-15-oic acid (2), formula C₂₄H₃₂O_4, has cell parameters a = 8.7035(3), b = 14.2020(4), c = 17.1590(5) Å, V = 2120.97(11) Å³, Z = 4.     

Structures of Three New (Phenylsulfonyl)Indole Derivatives

Abstract  

Three new 1-(phenylsulfonyl)indole derivatives, 3-acetyl-2-ethyl-1-(phenylsulfonyl)indole, (I), 2-benzyl-1-(phenylsulfonyl)indole, (II), and 3-trimethylsilylethynyl-1-(phenylsulfonyl)indole, (III), have been synthesized and their crystal structures determined by single crystal X-ray crystallography. (I), C₁₈H₁₇NO₃S, is triclinic with space group P-1 and cell constants: a = 8.6129(2) Å, b = 8.8366(2) Å, c = 11.0108(2) Å, α = 72.7920(1)°, β = 75.0120(1)°, γ = 77.2550(1)°, V = 763.79(3) ų and Z = 2. (II), C₂₁H₁₇NO₂S, is monoclinic with space group P21/n and cell constants: a = 10.8355(18) Å, b = 10.6987(19) Å, c = 14.472(3) Å, β = 75.0120(1), V = 1675.2(5) ų and Z = 4. (III), C₁₉H₁₉NO₂SSi, is monoclinic with, space group P21/c and cell constants: a = 12.9596(1) Å, b = 10.543(3) Å, c = 13.543(2) Å, β = 93.58°, V = 1846.8(6)ų and Z = 4. All three have the same (phenylsulfonyl)indole skeleton with different ligands attached to the 2- and 3-sites of the indole ring. The angle between the mean planes of the indole and benzyl groups is 76.9(6)° (I), 82.9(3)° (II), 89.6(2)° (III) and between the sulfonyl group with the indole and benzyl rings is 61.2(9)° (I), 59.0((5)° (II), 51.5(6)°, 42.5(8)° (III) and 51.5(6)°(I), 44.3(8)° (II), 47.2(8)° (III), respectively. In addition to the ligand substitutions, weak intermolecular C–H···O hydrogen bond interactions and π stacking interactions between the π orbitals of nearby indole and phenyl rings influence these twist angles. Comparison to a MOPAC AM1 computational calculation supports these observations.     

Intramolecular Carbonyl–Carbonyl Interaction as the Directing Motif of the Opposed Conformational Preferences Among [4?+?2] Cycloadducts of 3-Ethoxycarbonyl- and 3-Acetyl-Coumarins with 2,3-Dimethyl-1,3-Butadiene

Abstract  

In this work, the molecular structures of the Diels–Alder adducts: ethyl (6aR/S,10aR/S)-6a,7,10,10a-tetrahydro-8,9-dimethyl-6-oxodibenzo[b,d]pyran-6a-carboxylate C₁₈H₂₀O₄ 1 and (6aR/S,10aR/S)-6a-acetyl-6a,7,10,10a-tetrahydro-8,9-dimethyl-6-oxodibenzo[b,d]pyran C₁₇H₁₈O₃ 2; and the epoxide of this last (6aR/S,7aR/S,8aS/R,9aR/S)-6a-acetyl-6a,7,7a,8a,9,9a-hexahydro-7a,8a-dimethyl-6-oxo-6H-5,8-dioxacyclopropa[b]phenanthrene C₁₇H₁₈O₄ 3, are comparatively analyzed. Compound 1 is triclinic, space group P-1 with a = 7.7529(6) ?, b = 9.8625(8) ?, c = 11.3103(9) ?, α = 109.387(9)°, β = 95.484(1)°, γ = 99.753(1)°, Z = 2. Compound 2 is monoclinic, space group Cc, a = 7.7285(7) ?, b = 16.6813(15) ?, c = 11.3213(10) ?, β = 92.470(2)°, Z = 4. Compound 3 is monoclinic, space group P2 ₁ /c a = 11.2036(10), b = 15.8326(14), c = 8.3182(7), β = 90.600(2)°, Z = 4. The molecular structures of compounds 1–3 show conformational differences between lactone and 6a-acyl carbonyls. CO···CO dipolar interactions stabilize the less favoured syn conformation in 2–3, conclusions are supported on theoretical calculations. The molecular structure of compound 3 demonstrates that epoxidation of 2 leads to the stereo-selective addition of the oxygen atom.     

The Structure of the Copper(II) Complex with 4,5-Dichlorophthalic Acid: The 1:1 Complex ‘Adduct’ Salt <Emphasis Type="Italic">trans</Emphasis>-Tetraaqua(2-carboxy-4,5-dichlorobenzoato)(4,5-dichlorobenzene-1,2-dicarboxylic acid)copper(II) 2-Carboxy-4,5-dichlorobenzoate

Abstract  

The unusual (1:1) complex ‘adduct’ salt of copper(II) with 4,5-dichlorophthalic acid (H₂DCPA), having formula [Cu(H₂O)₄(C₈H₃Cl₂O₄) (C₈H₄Cl₂O₄)]·(C₈H₃Cl₂O₄) has been synthesized and characterized using single-crystal X-ray diffraction. Crystals are monoclinic, space group P2₁/c, with Z = 4 in a cell with dimensions a = 20.1376(7), b = 12.8408(4) c = 12.1910(4) Å, β = 105.509(4)°. The complex is based on discrete tetragonally distorted octahedral [CuO₆] coordination centres with the four water ligands occupying the square planar sites [Cu–O, 1.962(4)–1.987(4) Å] and the monodentate carboxyl-O donors of two DCPA ligand species in the axial sites. The first of these bonds [Cu–O, 2.341(4) Å] is with an oxygen of a HDCPA monoanion, the second with an oxygen of a H₂DCPA acid species [Cu–O, 2.418(4) Å]. The un-coordinated ‘adduct’ molecule is a HDCPA counter anion which is strongly hydrogen-bonded to the coordinated H₂DCPA ligand [O···O, 2.503(6) Å] while a number of peripheral intra- and intermolecular hydrogen-bonding interactions give a two-dimensional network structure.     

Bis[(2,3,4-Trimethoxy-Benzylidenepropylideneamino)Phenyl]Ether: Synthesis,Characterization and Crystal Structure

Abstract  

New Schiff base compound bis[(2,3,4-trimethoxy-benzylidenepropylideneamino)phenyl]-ether (1) was synthesized and characterized by elemental analyses (CHN), FT-IR and ¹H-NMR spectroscopy and single-crystal X-ray diffraction. The title compound 1 crystallizes in triclinic system, space group P-1, with a = 6.8255(4) Å, b = 10.4346(4) Å, c = 19.4166(8) Å, α = 86.588(3)°, β = 85.019(4)°, γ = 89.042(4)°, V = 1375.12(11) Å³ and Z = 2. It displays a trans configuration about the C=N double bonds.     

Synthesis,Crystal Structures and Fluorescence Properties of Ni (II) and Cu (II) Complexes with 1-(Furan-2-ylmethylene)-4-phenylthiosemicarbazone

Abstract  

Two coordination complexes, NiL ₂ and CuL ₂ {L = bis[1-(furan-2-ylmethylene)-4-phenylthiosemicarbazone]}, were synthesized and determined by X-ray crystallography. Both crystallize in the Orthorhombic system, space group Pbcn, with lattice parameters: a = 11.935 (2) Å, b = 15.314(3) Å, c = 12.952(3) Å and Z = 4 for Ni (II); a = 20.850(4) Å, b = 15.049(3) Å, c = 7.5633(5) Å and Z = 4 for Cu (II). In both complexes, the central metal atom is coordinated in a distorted square-planar with two ligands through two S and N atoms, respectively. The EA, UV, IR and TG-DTG were studied and the possible structures of the complexes were speculated. Moreover, the fluorescence of the complexes were studied. The results reveal that copper complex can emit purple fluorescence in solvents.     

Synthesis,Crystal Structure and Optical Properties of a Three-Dimensional Supramolecule Assembled by a Dinuclear Neodymium Cluster

Abstract  

The reaction of isonicotinic acid (IN), sodium hydroxide, 1,10-phenanthroline (phen) and neodymium nitrate leads to the formation of a novel complex [Nd(phen)(IN)₂(NO₃)(H₂O)₂]₂ 1, which has been characterized by single crystal X-ray diffraction analysis: monoclinic, space group C2/c, with a = 24.93(2) Å, b = 9.452(3) Å, c = 21.406(5) Å, β = 97.87(2)°, and Z = 4. Complex 1 consists of a centrosymmetric dinclear molecule, and neodymium atoms are bridged by two carboxyl groups of two IN ligands. The dinuclear clusters of 1 are connected each other into a three-dimensional (3D) supramolecular framework, which is stabilized by O–H···O, O–H···N hydrogen bonds as well as π–π stacking interactions. Its electronic absorption and luminescence properties have also been investigated.     

Hydrogen Bonding in Proton-Transfer Compounds of 5-Sulfosalicylic Acid with a Series of Aliphatic Nitrogen Lewis Bases

Abstract  

The crystal structures of the proton-transfer compounds of 5-sulfosalicylic acid (3-carboxy-4-hydroxybenzenesulfonic acid) with the aliphatic nitrogen Lewis bases, hydroxylamine, triethylamine, pyrrolidine, morpholine, N-methylmorpholine and piperazine, viz. hydroxyammonium 3-carboxy-4-hydroxybenzenesulfonate (1), triethylaminium 3-carboxy-4-hydroxybenzenesulfonate (2), pyrrolidinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate (3), morpholinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate (4), N-methylmorpholinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate (5) and piperazine-1,4-diium bis(3-carboxy-4-hydroxybenzenesulfonate) hexahydrate (6) have been determined and their comparative structural features and hydrogen-bonding patterns described. Crystals of 4 are triclinic, space group P-1 while the remainder are monoclinic with space group either P2₁/c (1–3) or P2₁/n (5, 6). Unit cell dimensions and contents are: for 1, a = 5.0156(3), b = 10.5738(6), c = 18.4785(9) ?, β = 96.412(5)^o, Z = 4; for 2, a = 8.4998(4), b = 12.3832(6), c = 15.4875(9) ?, β = 102.411(5)^o, Z = 4; for 3, a = 6.8755(2), b = 15.5217(4), c = 12.8335(3) ?, β = 92.074(2)^o, Z = 4; for 4, a = 6.8397(2), b = 12.9756(5), c = 15.8216(6) ?, α = 90.833(3), β = 95.949(3), γ = 92.505(3)^o, Z = 4; for 5, a = 7.0529(3), b = 13.8487(7), c = 15.6448(6) ?, β = 90.190(6)^o, Z = 4; for 6, a = 7.0561(2), b = 15.9311(4), c = 12.2102(3) ?, β = 100.858(3)^o, Z = 2. The hydrogen bonding generates structures which are either two-dimensional (2 and 5) or three-dimensional (1, 3 , 4 and 6). Compound 6 represents the third reported structure of a salt of 5-sulfosalicylic acid having a dicationic piperazine species.     

A Sodium Supported Borate Ester: Synthesis,Spectral Characterization and Crystal Structure of dimeric Sodium Organoborate Complex [Na(py)][B(hyncaH<Subscript>−2</Subscript>)<Subscript>2</Subscript>]<Subscript>2</Subscript>

Abstract  A dimeric sodium supported borate complex, [Na(py)][B(hyncaH₋₂)₂]₂ (1) (py = pyridine, hynca = 1-hydroxynaphthalene-2-carboxylic acid), has been synthesised by the reaction of NaBH₄ with two equivalents of hynca in anhydrous THF and following crystallization from py/H₂O solution afforded borate ester derivative. The complex has been fully characterized by FT-IR in the solid state and by NMR (¹H and ¹³C) spectroscopy and electrospray ionization mass spectrometry in solution. The molecular structure of the title compound was determined by single crystal X-ray diffraction. Structure analysis of complex 1 confirmed the presence of an anionic complex [B(hyncaH₋₂)₂]⁻ in which boron atom is coordinated simultaneously by two hynca ligands utilising both alkoxide and carboxylate groups for bonding. The Na atom is six- coordinate to five O atoms of hydroxy carboxylic acid and one pyridine N atom. Crystal data: crystal system, monoclinic, a = 10.971(3) Å, b = 6.839(3) Å, c = 30.545(5) Å, β = 92.20(2)°, space group P2₁/c (#14), V = 2,290(1) Å³, Z = 4. Index Abstract  There are limited examples of alkali metal supported borate ester complexes.      

Synthesis and Crystal Structure of a Depside Derivative 2-(2-Methoxy-2-oxoethyl)phenyl 2-(3,4-Dimethoxyphenyl)acetate

Abstract  

A depside derivative, 2-(2-methoxy-2-oxoethyl)phenyl 2-(3,4-dimethoxyphenyl)acetate (3), was synthesized through a facile approach in high yields. Its structure was confirmed by ¹H NMR, ¹³C NMR, ESI mass spectra, elemental analyses and X-ray single crystal diffraction study. Crystal structure analysis revealed that compound 3 crystallized in the monoclinic, space group P2₁/c with the following unit cell parameters: a = 10.173(2) Å, b = 10.459(2) Å, c = 16.516(3) Å, α = 90°, β = 102.30(3)°, γ = 90°, V = 1717.0(6) Å³, Z = 4.     

Piperazinium Chlorocuprates(I)

Abstract  The formation from aqueous solution of networks containing piperazinium hydrochlorides with copper(I) chloride is described. Four new X-ray crystal structures are reported: (H₂Pip)[Cu₂Cl₄] (two isomeric phases: 1A and 1B), (H₂MePip)[Cu₃Cl₅] (2), and (H₂Me₂Pip)[Cu₄Cl₆] (3) (Pip = piperazine, MePip = N-methylpiperazine, Me₂Pip = N,N′-dimethylpiperazine. In 1A (P-1, a = 6.3141(2), b = 6.8248(2), c = 6.9067(2), α = 90.707(2), β = 110.748(2), γ = 110.799(2), V = 256.918(13), Z = 2) corner-sharing Cu₂Cl₂ rhomboid dimers form infinite chains running parallel to the a-axis. In 1B (Pbcn, a = 9.9442(6), b = 8.0622(5), c = 13.1301(7), V = 1052.67(11), Z = 8) the Cu₂Cl₂ dimers are linked by μ-Cl into Cu₆Cl₈ rings which form hexagonally tiled sheets running parallel to the a,b-plane. In 2 (P-1, a = 8.0815(7), b = 9.6584(9), c = 9.7900(8), α = 70.231(4), β = 77.180(4), γ = 70.587(4), V = 673.05(10), Z = 2) alternating Cu₃Cl₃ and Cu₄Cl₄ rings are fused to form ribbons that run parallel to the a-axis. Copper-copper interactions are present. In 3 (C2/c, a = 17.4026(6), b = 10.5295(4), c = 11.7501(8), β = 131.5490(10), V = 1611.35(14), Z = 8) relatively long Cu···Cl interactions connect Cu₄Cl₆ “adamantane” units into chains running parallel to the c-axis. In all cases the piperazinium ions are independent from the chlorocuprate structures, but they do show N–H···Cl interactions. Index Abstract  The synthesis and network structures of four piperazinium hydrochlorides with copper(I) chloride are presented.      

Hydrogen Bonded 3D Supramolecular Architectures of Two Organic Salts Assembled from 2-Aminoheterocyclic Compounds and Phosphoric Acid

Abstract  

Two phosphate salts (2-aminopyrimidine): (phosphoric acid): H₂O [HL1⁺ (H₂PO₄) ⁻ ]·H₂O (1), and (4-phenylthiazol-2-amine): (phosphoric acid) [HL2⁺·(H₂PO₄)⁻] (2) based on 2-aminoheterocyclic compounds, 2-aminopyrimidine (L1), and 4-phenylthiazol-2-amine (L2) were prepared and structurally characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic, space group P-1, with a = 6.2201(7) Å, b = 8.6139(9) Å, c = 9.4800(10) Å, α = 109.685(2)°, β = 106.3340(10)°, γ = 95.4450(10)°, V = 448.72(8) Å³, Z = 2. For 1, the cations were linked to each other via intermolecular C–H···N hydrogen bonds to form a 1-D chain structure running along the a-axis direction. The anions and the water molecules were connected alternatively along the a-axis direction through O–H···O hydrogen bonds to form a 1-D chain also. The cationic chains and the anionic chains were alternatively connected along the c-axis direction through N–H···O and C–H···O hydrogen bonds to form a 2D corrugated sheet. Adjacent sheets were combined together through π–π interaction to form double sheet. These double sheets were further joined together by O–H···O and N–H···O hydrogen bonds to produce a 3D network structure. Compound 2 crystallizes in the Orthorhombic, space group Pbca, with a = 10.1929(10) Å, b = 8.4406(9) Å, c = 27.589(2) Å, α = 90°, β = 90°, γ = 90°, V = 2373.6(4) Å³, Z = 8. In 2, the phosphates formed 1D chain along the b-axis through two P–O–H···O = P hydrogen bonds. The cations formed 1D zigzag chain along the b-axis direction under the CH–π interaction. The anionic chains were intercalated between two adjacent cationic chains through N–H···O, O–H···O, C–H···O, and O–S contacts. Such stacking repeated along the c-axis direction to form a 3D network structure.     

Synthesis and Crystal Structure of 3-Methyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole

Abstract  

The title compound, 3-methyl-4-phenyl-5-(2-pyridyl)-1,2,4-triazole was synthesized by reaction of diphenylphosphazoanilide with N-acetyl-N′-(2-pyridoyl)hydrazine. Crystals suitable for X-ray analysis were obtained from a mixed solution of water and ethanol in a one-to-one volume ratio. The crystal is orthorhombic, space group P2₁2₁2₁ with crystallographic parameters: a = 19.414(4) Å, b = 17.172(3) Å, c = 7.4850(15) Å, β = 90.00°, μ = 0.079 mm⁻¹, V = 2495.3(8) Å³, Z = 8, Dc = 1.258 g/cm³, F(000) = 992, T = 295(2) K. The X-ray results showed that in the crystal structure of the title compound, the 1,2,4-triazole, pyridine and benzene rings are not coplanar.     

Crystal Structures of a Series of 1,1-Spiro-bis(1,2,3,4-tetrahydronaphthalene)-Based Derivatives

Abstract  

The structures of four spirobisnaphthalenes based monomers 1, 2, 3a and 3b are reported. Each compound represents a methoxylated precursor which after deprotection led to the formation of a monomer successfully used for the synthesis of Polymers of intrinsic microporosity. The spiro-centre represents the site of contortion that, since its rigidity, leads to inefficient packing in the solid state inducing microporosity in the final polymer. Compound 1 crystallized in the monoclinic P2/c space group with unit cell parameters a = 8.1659(19) ?, b = 7.5298(18) ?, c = 19.130(5) ?, β = 97.935(4)°, V = 1165.0(5) ?³, Z = 2, D = 1.210 Mg m⁻³. Compound 2 crystallized in the monoclinic P2₁/n space group with unit cell parameters a = 12.6940(9) ?, b = 7.7267(6) ?, c = 19.9754(15) ?, β = 97.220(1)°, V = 1943.7(3) ?³, Z = 4, D = 1.355 Mg m⁻³. Compound 3a crystallized in the monoclinic P2₁/c space group with unit cell parameters a = 16.8137(14) ?, b = 10.5577(9) ?, c = 31.344(3) ?, β = 103.618(1)°, V = 5407.5(8) ?³, Z = 8, D = 1.308 Mg m⁻³. Compound 3b crystallized in the monoclinic Pc space group with unit cell parameters a = 15.594 ?, b = 12.564 ?, c = 18.339 ?, β = 90.224(1)°, V = 3593.0 ?³, Z = 4, D = 1.236 Mg m⁻³.     

Synthesis,Crystal Structures and Physicochemical Properties of Poly[bis(<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-Dimethylformamide)tetra(thiocyanato)metal(II) Mercury(II)] (Metal = Cadmium and Manganese)

Abstract  

Two novel single crystals, poly[bis(N,N-dimethylformamide)tetra(thiocyanato)metal(II)mercury(II)] (metal = cadmium and manganese, abbreviated as DTCM and DTMM, respectively) were prepared. The characterizations of DTCM and DTMM were performed by elemental analyses, infrared, X-ray single crystal diffraction. The two title complexes crystallized in the same monoclinic crystallographic system and P2₁/n space group with unit cell parameters: a = 9.2515(2) Å, b = 14.1670(3) Å, c = 16.5898(3) Å, β = 93.0320(10)°, z = 4, D _x  = 2.115 g/cm³ for DTCM, and a = 9.24580(10) Å, b = 14.1110(2) Å, c = 16.4937(2) Å, β = 92.9120(10)°, z = 4, D _x  = 1.960 g/cm³ for DTMM, respectively. The two structures are isostructural. The thermal decomposition processes of the two crystals were investigated by means of thermogravimetric analysis and differential thermal analysis measurements in air.     

Ethynyl and Propynylpyrene Inhibitors of Cytochrome P450

Abstract  

The single-crystal X-ray structures and in vivo activities of three aryl acetylenic inhibitors of cytochromes P450 1A1, 1A2, 2A6, and 2B1 have been determined and are reported herein. These are 1-ethynylpyrene, 1-propynylpyrene, and 4-propynylpyrene. To investigate electronic influences on the mechanism of enzyme inhibition, the experimental electron density distribution of 1-ethynylpyrene has been determined using low-temperature X-ray diffraction measurements, and the resulting net atomic charges compared with various theoretical calculations. A total of 82,390 reflections were measured with Mo Kα radiation to a (sinθ/λ)_max = 0.985 Å⁻¹. Averaging symmetry equivalent reflections yielded 8,889 unique reflections. A least squares refinement procedure was used in which multipole parameters were added to describe the distortions of the atomic electron distributions from spherical symmetry. A map of the model electron density distribution of 1-ethynylpyrene was obtained. Net atomic charges calculated from refined monopole population parameters yielded charges that showed that the terminal acetylenic carbon atom (C18) is more negative than the internal carbon (C17). Net atomic charges calculated by ab initio, density functional theory, and semi-empirical methods are consistent with this trend suggesting that the terminal acetylenic carbon atom is more likely to be the site of oxidation. This is consistent with the inhibition mechanism pathway that results in the formation of a reactive ketene intermediate. This is also consistent with assay results that determined that 1-ethynylpyrene acts as a mechanism-based inhibitor of P450s 1A1 and 1A2 and as a reversible inhibitor of P450 2B1. Crystallographic data: 1-ethynylpyrene, C₁₈H₁₀, P2₁/c, a = 14.571(2) Å, b = 3.9094(5) Å, c = 20.242(3) Å, β = 105.042(2)°, V = 1,113.5(2) Å³; 1-propynylpyrene, C₁₉H₁₂, P2₁/n, a = 8.970(2) Å, b = 10.136(1) Å, c = 14.080(3) Å, β = 99.77(2)°, V = 1,261.5(4) Å³; 4-propynylpyrene, C₁₉H₁₂, Pbca, a = 9.904(1) Å, b = 13.174(2) Å, c = 19.401(1) Å, V = 2,531.4(5) Å³.