The preparation, characterization, and X-ray structural analysis of dichlorobis[1-methyl-3-(2-propyl) -2(3H)-imidazolethione]mercury(II)

A new compound of mercury(II) chloride complexed to 1-methyl-3-(2-propyl) -2(3H)-imidazolethione (mipit) has been prepared and characterized via standard methods and X-ray crystallography. The structural significance of this study is that it shows one of the few monomeric examples of a mercury(II) chloride thione complex reported to date. The compound crystallizes in space group P2₁/c with a = 17.143(6) Å, b = 17.047(6) Å, c = 14.759(5) Å, = 105.899(5)°, V = 4148(2) ų, Z = 8. The coordination sphere is distorted tetrahedral with Hg–S bonds and Hg–Cl bond distances falling within the normally expected ranges. Bond angles ranged from 108.11(4)° to 115.51(4)° with the widest angle being observed for the S–Hg–S linkage. Ligand bond distances and angles including the C=S distance are within the normally expected values observed for this compound.     

Crystal structure of 2,3-bis(2-pyridyl)-5, 8-dimethoxyquinoxaline

Crystals of 2,3-bis(2-pyridyl)-5,8-dimethoxyquinoxaline (bpdmq) were examined using X-ray diffraction analysis: Monoclinic, space group P2 ₁/n with a = 6.9362(14) Å, b =17.285(4) Å, c =13.583(3) Å, =96.21(3)°, V =1619.0(6) ų, Z = 4. The crystal structure indicates that the title compound consists of quinoxaline ring system substituted with two pyridine rings and two methoxy groups. Two pyridine rings form dihedral angles of 39.8 and 44.1° with the mean planar quinoxaline ring, and a dihedral angle of 67.1° with each other. The orientation of the pyridine rings is such that their N atoms face each other. There exist significant – interactions responsible for the formation of the stacks along the a-axis of the crystal packing.     

The molecular structure of acetato[2-(pyridin-2′-yl)phenyl]mercury(II)

The crystal structure of the title compound was determined by X-ray crystallography. The compound crystallizes in the monoclinic crystal system witha=8.152(4),b=17.994(7),c=8.634(9) Å, =108.92(5)°, space group P2₁/c (N:14),V=1198.02 ų,Z=4. The mercuryl(II) atom forms two strong, almost colinear bonds (bond angle 176.1(4)°) with a carbon of the phenyl ring (Hg–C=1.99(1) Å) and one of the acetate oxygen atoms (Hg–O(1)=2.005(7) Å). These primary bonds are supplemented by secondary intramolecular interactions with the pyridine nitrogen (Hg...N=2.727(9) Å) and the other acetate oxygen (Hg...O(2)=2.925(8) Å), although the latter is very weak and the acetate anion therefore practically monodentate. Weak additional intermolecular Hg–C and Hg–O(1)interactions contribute to the lattice structure.     

Crystal structure of bis[dihydrobis(3,5-dimethy-1-pyrazolyl)borato]cadmium(II)

The structure of [H₂B(3,5-Me₂pz)₂]₂Cd shows the four nitrogen donor atoms form a pseudotetrahedral arrangement about the cadmium(II). The intraligand N—Cd—N angles are restricted to an average of 91.4° by the chelate rings forcing the interligand N—Cd—N bond angles to average 119.4°. The Cd—N bond distances average 2.21 Å with a range of 0.04 Å. The crystal is in the triclinic space group, P with a = 7.6793(2) Å, b = 8.5992(2) Å, c = 25.0874(4) Å, = 91.0791(2)°, = 97.9769(4)°, = 110.2344(6)°, and Z = 2.     

The crystal structures of (p-ClPh)3PO and (p-OMePh)3PO, including an analysis of the P-O bond in triarylphosphine oxides

The crystal structures of the compounds tris(para-chlorophenyl)phosphine oxide {(p-ClPh)₃PO} and tris(para-methoxyphenyl)phosphine oxide {(p-OMePh)₃PO} were determined by X-ray diffraction methods. (p-ClPh)₃PO crystallizes in the space group P-1 (no. 2) with a = 11.828(2), b = 12.645(2), c = 14.072(2) Å, = 97.90(1), = 109.45(1), = 115.43(1), V = 1692.3(2) ų and Z = 4. The mean O–P and C–P distances are 1.481(6) and 1.806(2) Å, respectively, and the mean C–P–C angle is 106.5(1.1). (p-OMePh)₃PO crystallizes in the space group P2₁/c (no. 14) with a = 18.8642 (10), b = 10.3999(5), c = 21.3462(16) Å, = 115.414(6)°, V= 3782.6(4) ų, and Z = 8. The mean O–P and C–P distances are 1.484(5) and 1.798(4) Å, respectively, and the mean C–P–C angle is 106.5(1.0). These two structures were analyzed along with the previously determined structures of triphenylphosphine oxide {Ph₃PO} and tri-p-tolylphosphine oxide {(p-MePh)₃PO}, and IR data were collected on all four compounds. Both the observed P–O distances and the IR stretching frequencies for these triarylphosphine oxides support the interpretation of the P–O bond as having substantial multiple-bond character, with a bond order between 1.7 and 1.8. The para-substituents on these triarylphosphines were shown to have a statistically insignificant effect on the P–O bond.     

The crystal and molecular structure of bis(melamine)silver(I) perchlorate, Ag(C3H6N6)2ClO4

The crystal structure of the title compound, Ag(mela)₂ClO₄ (mela = melamine), has been investigated by X-ray diffraction techniques, the crystals are triclinic, space group P1¯, with a = 5.236(2), b = 7.5385(9) c = 19.063(3) Å, = 99.91(1), = 90.53(2), = 108.32(2)° and Z = 2. The Ag atom has a coordination geometry with two strong bonds (2.162(2) and 2.179(4) Å) to the nitrogen of the melamines and two weak bonds (2.776(4) and 2.785(4) Å) to oxygen atoms of the ClO^– ₄anions. The N—Ag—N vector is markedly nonlinear (angle at Ag 167.7(2)°).     

Crystal structure of aquo (hydroxo) (ethylenediaminetetraacetato) sodium(I) tin(IV), NaSn(OH)(edta)(H2O)

NaSn(OH)(edta)(H₂O) is monoclinic, space groupP2₁/c, witha=9.747(3)Å,b=9.121(3)Å,c=16.430(6)Å, =98.69(4)°, ų, andZ=4. The coordination environment of Sn(IV) is a capped octahedron. Sn–O distances range from 1.990(6)Å to 2.351(7)Å. Na(I) is five coordinated to three different edta molecules. Na–O distances range from 2.283(9)Å to 2.414(7)Å. The edta ligand presents the E, G/R conformation. The crystal structure is composed of sheets parallel to (001): inside a sheet Sn(OH)(edta) molecules are connected to each other by the Na(I) interactions.     

Synthesis and crystal structure of bis(benzimidazolium) tetrahalocobaltate(II)

The crystal structures of benzimidazolium tetrahalocobaltates (HBz)₂[CoX₄] (X = Cl and Br) have been determined. The chloride salt is triclinic, P-1, with a = 7.670(3) Å, b = 8.307(3) Å, c = 15.730(2) Å, and = 87.37(3)°, = 84.99(3)°, = 67.72(2)°. The bromide salt is monoclinic, C2/c, with a = 15.568(2) Å, b = 8.063(3) Å, c = 5.762(2) Å and = 91.36(3)°. The structures of the two salts are closely related. Both the compounds contain isolated tetrahedral CoX₄ ^2– anions and benzimidazolium cations. In the chloride salt, three chloride ions are involved in strong hydrogen bonding while only two bromide ions participate in the bromide salt. The greater deviation from the ideal tetrahedral geometry in CoBr₄ ^2– can be related to the less extensive hydrogen-bonding network compared to the chloro complex.     

Synthesis and crystal structure of bis(2-methylbenzimidazolium) tetrahalocuprate(II)

The crystal structures of 2-methylbenzimidazolium tetrahalocuprates (H2-mebz)₂[CuX₄] (X = Cl and Br) have been detemined. The chloride salt is monoclinic, P2₁/c, with a = 8.540(2) Å, b = 16.591(2) Å, c = 14.303(3) Å, and = 98.69(2)°. The bromide salt is also monoclinic, P2₁/c, with a = 8.316(3) Å, b = 17.436(3) Å, c = 14.747(3) Å, and = 98.82(3)°. Both the compounds contain discrete distorted tetrahedral CuX₄ ^2– anions and almost planar 2-methylbenzimidazolium cations. In the chloride salt, three chloride ions are involved in hydrogen bonding instead of two bromide ions in the bromide salt.     

Mercury complexes with thiacrowns: the crystal structure of bis(1,4,7-trithiacyclodecane) mercury(II) hexafluorophosphate

We report the synthesis, crystal structure, and NMR spectroscopy for the mercury(II) complex with the crown thioether 1,4,7-trithiacyclodecane (10S3) , bis(1,4,7-trithiacyclodecane) mercury(II) hexafluorophosphate (1). The 10S3 ligand coordinates in tridentate fashion and readily forms a distorted bis octahedral complex, an unusual coordination geometry for Hg(II). The crystal structure shows the two 10S3 ligands arranged in a trans or anti fashion around the mercury center, yielding the meso stereoisomer. Bond distances and angles are very comparable to those found in the structure of the perchlorate salt of the complex cation although the hexafluorophosphate salt shows slightly longer and more varied Hg–S distances (2.623(2) , 2.708(2), 2.784(2) Å) with a tetragonal elongation. The ¹⁹⁹Hg¹H NMR spectrum exhibits a single resonance with a chemical shift at –596 ppm consistent with a hexakis(thioether) coordination environment around the mercury center. Crystal data for 1: C2/c, a = 19.184(3) Å, b = 15.235(2) Å, c = 11.3791(15) Å, = 123.358(2)°, V = 2777.9(6) ų, Z = 4.     

Crystal structure and EPR spectra of glycilglycilglycinocopper(II)bromide sesquihydrate

The title compound, Cu(glyglygly)Br·1·5H₂O, crystallizes in the space group C2/c, with a = 21.468(7), b = 6.716(5), c = 16.166(6) Å, = 98.39°, and Z = 8. The tripeptide is bonded to one Cu(II) ion through the nitrogen [Cu–N=1.97(1)Å] and oxygen [Cu–O=2.019(8)Å] atoms of the amino end glycine residue and to another Cu(II) through one oxygen atom [Cu–O=1.931(9)Å] of the terminal carboxyl group. This give rise to covalently bonded and infinite ···–Cu–tripeptide–Cu–··· chains. These chains are linked to one another by a network of H-bonds involving the water molecules and bromide ions. The Cu(II) ion is in a distorted tetragonal pyramidal coordination polyhedron. At the corner of the base of the pyramid are the terminal glycine nitrogen and oxygen atoms of one tripeptide, a carboxylic oxygen of another tripeptide and a bromide ion. The fivefold coordination is completed with a water molecule at the top of the pyramid [Cu–Ow=2.286(9)Å]. For all orientations of the applied magnetic field the single crystal EPR spectra display a single anisotropic exchange collapsed resonance without hyperfine structure. Its position was measured in three perpendicular planes and the crystal g-tensor evaluated from the data. This tensor is interpreted in terms of the contributing Cu(II) complexes in the unit cell to deduce the principal values g₁ = 2.273, g₂ = 2.050 and g₃ = 2.131 for the molecular gyromagnetic tensor. We also discuss the magnitude of the exchange interaction between neighboring copper ions in the lattice on the basis of the features in the EPR spectra and the structural information.     

Crystal and molecular structure of dibenzoyl disulfide

Crystals of dibenzoyl disulfide, C₁₄H₁₀O₂S₂, are monoclinic, space group P2₁/c, with the cell dimensions (294 K), a = 12.356 (1), b = 12.071 (1), c = 9.071 (2) Å, = 107.15(1)°, V =1292 (3) ų with D _m = 1.42, D _x = 1.411 g cm^–3, and Z = 4. Complete three-dimensional data was collected on a CAD-4 diffractometer using the /2 method, the crystal structure was solved using MULTAN and refined by full-matrix least-squares methods to a final R value of 0.036 for 2738 observed reflections. The S–S bond distance is 2.021(1) Å and has a partial double-bond character. The dihedral angle around the disulfide bond is 80.8°. The two S–C distances are 1.805(2) and 1.823(2) Å. The central part of the molecule (C–S–S–C) adopts a skewed nonplanar configuration and the planes of the two benzene rings are inclined at an angle of 93.7°. The S–S bond direction from the X-ray could be compared with the directions of g _min for (S–S) anion and g _max for (S–S) cation deduced from electron spin resonance spectroscopy. The former makes an angle of 4.6° and the latter makes an angle of 18.1° with the S–S bond direction.     

Crystal structure and conformation of the antimalarial drug 5,7-methoxy-8-(3-methyl-1-buten-3-ol)-coumarin

The crystal and molecular structure of the antimalarial compound 5,7-methoxy-8-(3-methyl-1-buten-3-ol)-coumarin, C₁₆H₁₈O₅, M _r = 290.3 Da, has been determined from X-ray diffraction data. The material crystallizes in the monoclinic space group P2₁/c with 4 molecules per unit cell of dimensions a = 8.9044(9), b = 17.623(1), c = 10.175(1) Å, = 113.97(1)°, crystal density D _c = 1.322 g/cm³. The structure was determined using direct methods and refined by full-matrix least squares to a conventional R index of 0.066 for 2416 measured reflections and 206 parameters.The coumarin ring system is almost planar with the methoxy C atoms rotated slightly out of the coumarin mean plane. Apart from the terminal CH₃ groups C(12) and C(13), which are 1.184(3) Å above and –1.315(3) Å below the plane, the 3-methyl-1-buten-3-ol substituent is planar (rms deviation 0.009 Å) making an angle of 6.31(7)° with the phenyl ring. One intermolecular hydrogen bond is present in the crystal structure between O(5)–HO(5) and the symmetry related O(2) oxygen, generated by the symmetry operation (x, 1/2 – y, –1/2 + z).     

Synthesis, spectroscopy, magnetism, and X-ray structures of hexakis(1-(2-chloroethyl)-tetrazole-N4)copper(II) salts

The compounds hexakis(1-(2-chloroethyl)-tetrazole-N4)copper(II) tetrafluoroborate mono(1-(2-chloroethyl)-tetrazole) (1) and hexakis(1-(2-chloroethyl)-tetrazole-N4) copper(II) perchlorate mono(1-(2-chloroethyl)-tetrazole) (2) were obtained from the crystallization of 1-(2-chloroethyl)-tetrazole (teec) with the respective copper salt. The X-ray structures are reported. Both compounds crystallize in the monoclinic space group C2/c for 1: a = 25.754(3) Å, b = 18.162(3) Å, c = 10.298(2) Å = 104.294(7)° and Z = 4 and for 2: a = 25.745(3) Å, b = 18.197(3) Å, c = 10.29355(3) Å = 104.512(10)° and Z = 4. The Cu^II ions are octahedrally surrounded by six teec ligands. One free teec ligand is present in the structures. The Cu–N distances in the centrosymmetrical units are 2.01, 2.04, and 2.39 Å in both compounds, consistent with a Jahn–Teller elongated octahedron. The ligand field spectra of both compounds show a signal in the visible range at about 15.200 cm^–1 and by an EPR spectrum the following values are found: g _| = 2.29 and g = 2.03. The compounds are both paramagnetic and the T value of 0.37 cm^–1 K mol^–1, which is associated with S = 1/2, is what would be expected for a mononuclear Cu^II complex.     

Crystal structure of bis(2,4-pentanedionato)copper(II)

The structure of bis(acetylacetonato)copper(II) has been redetermined from single crystal X-ray diffraction data. The unit cell parameters area=11.331(9),b=4.697(3),c=10.290(9) Å, and=91.84(7)dg. A finalR=0.056 for 727 observed reflections was obtained. The O-Cu-O chelate (bite) angle is 93.2(2)°. The two Cu-O bond lengths are 1.914(4) and 1.912(4) Å. The complex has a slight chair structure and a step angle of 7.05°.     

Crystal structures of a series of 3,7-bis-(arylazo)-1,3,5,7-tetraazabicyclo[3.3.1]nonanes

The crystal and molecular structure of a series of 3,7-bis(arylazo)-1,3,5,7-tetraazabicyclo[3.3.1] nonanes (1a–d) have been determined by single crystal X-ray diffraction analysis. All four compounds have the same feature, that the tetraazabicyclononane unit assumes a cage-like structure with the aryltriazene moieties lying parallel to one another so that the aryl rings are held together by – stacking. Crystal data: 1a C₁₇H₁₈N₁₀O₄, triclinic, space group P – 1, a = 9.8899(10), b = 13.0845(13), c = 16.458(2) Å, = 94.095(2)°, = 107.004(2)°, = 111.027(2)°, V = 1863.5(3) ų and Z = 4; 1b, C₁₉H₁₈F₆N₈, orthorhombic, space group Pbca, a = 15.3210(8), b = 10.9512(6), c = 24.5698(13) Å, V = 4122.4(4) ų and Z = 8; 1c C₁₉H₁₈N₁₀, monoclinic, space group P2₁/n a = 6.3742(6), b = 13.7343(13), c = 21.542(2)Å, = 97.738(2)°, V = 1868.8(3) ų, and Z = 4; 1d, C₁₉H₁₈N₁₀, monoclinic, space group P2₁/c, a = 18.205(2), b = 17.398(2), c = 12.784(12) Å, = 109.480(2)°, V = 3818.0(6) ų, and Z = 8.     

Structure of a platinum(II) complex containing a benzothiazole derivative: [NEt4][Pt(3,4-dsb)Br3]

Tetraethylammoniumtribromo[2-(3.4-dimethoxy)styrylbenzothiazole]platinate(II), [(C₂H₅)₄N]-[PtBr₃(C₁₇H₁₅NO₂S)], monoclinic,P2₁/c,a=13.454(7),b=11.991(3),c=19.004(5) Å, = 108.92(3)°,V=2900(4) ų,Z=4,D _r=1.975 g cm^–3, (MoK)=0.71073 Å, =95.59 cm^–1,F(000)=1656,T=303 K, finalR=0.051 for 2262 unique observed reflections. The structure was solved by heavy atom and Fourier methods. The molecule is nearly planar, with a dihedral angle of only 3.57(7)° between the benzothiazole and phenyl rings. The C–S–C angle in the thiazole ring is 91(1)°.     

X-ray crystal structures of twocis-Mo(CO)4{(Ph2PO)2P(O)R} (R=Me,MeO-p-C6H4) complexes with unusual Mo-PPh2-O-P(O)R-O-PPh2 chelate rings

The X-ray crystal structures of twocis-Mo(CO)₄{(Ph₂PO)₂P(O)R} (I:R=Me; II: R=C₆H₄-p-OMe) complexes are presented. Complex I crystallizes in the monoclinic space groupP2₁/n (a=11.566(1),b=10.045(2),c=25.959(4)Å;=97.64(1)°;V=2989.0 ų;Z=4). Complex II crystallizes in the triclinic space group P¯1 (a=8.868(2),b=11.552(2),c=16.818(3)Å,=78.32(1)°,=93.70(2)°, =86.59(2)°,V=1679.0 ų,Z=2). The coordination geometry of the molybdenum in each of these complexes is a slightly distorted octahedron. The six-membered chelate rings in these complexes have twist boat configurations with both ends flattened. The two rings differ in the degree of twisting in the boat and in the degree to which both ends of the boat are distorted from the ideal configurations. The twisting is greater in II, but the distortion is greater in I. Both appear to be due to the differing sizes of the substituent on the phosphonate phosphorus with larger substituents giving less twisting and flattening.     

Crystal structure of trismorpholino phosphiniminocyclotrithiazene

The title compound (OC₄H₈N)₃P=N–S₃N₃ crystallizes in a monoclinic crystal system with unit cell parameters a = 8.9996(3), b = 17.2895(7), and c = 12.3648(9) Å, = 90.63(5)°, Z = 4, and space group P2₁/n. Strikingly the exocylic S1–N4 bond length is 1.545(3) ÅR and is accompanied by the largest angle at P–N4–S1 as 131.2(2)°. The tricoordinated sulfur atom of the cyclotrithiazene ring deviates from the mean plane of other five atoms by 0.654(1) Å.     

Crystal structure of 2,2,4,7,7-pentamethyl-3,6-dithiaoctane tetracarbonyl tungsten(0)

The x-ray crystal structure of the complex ²-PDOW(CO)₄ (five-membered ring, PDO = 2, 2, 4, 7, 7-pentamethyl-3,6-dithiaoctane) is reported. The complex crystallizes in the monoclinic crystal system, space group P2₁/c, [#14] with unit cell parameters a = 14.002(14) Å, b = 9.340(10) Å, c = 15.094(12) Å, = 92.67(4)°, V = 1972(3) ų; Z = 4. The arrangement of the ligands around the metal atom is distorted from octahedral geometry. Large C–O bond distances and short W–C bond distances of the carbonyl groups located at a trans position with respect to PDO is indicative of a trans influence. The W–S(1) and W–S(2) bond distances of 2.545(3) and 2.545(2) Å, respectively, are shorter than observed for closely related complexes.