Crystal structures of 4-amino-1,2,4-triazolidine-3,5-dione (urazine) (C2H4N4O2) and dichlorobis (4-amino-1,2,4-triazolidine-3,5-dione-N,O) copper (II) (C4H8Cl2CuN8O4)

Crystal structure analyses of urazine and of its adduct with CuCl₂ show that this ligand can exchange interactions of stacking that cannot be defined as simple - interactions. The copper atoms are octahedrally coordinated by two oxygen atoms and two aminic nitrogen from chelating uraxines and two chlorine atoms. The crystals of urazine are monoclinicP2₁ c:a=6.741(1),b=5.815(1),c=11.141(2) Å,/gb=92.13(1)°,V _c=436.4(1) ų,Z=4,R=0.0402 for 714 independent observed reflections; the crystals of [CuCl₂(urazine)₂] are triclinicP¯1:a=5.236(1),b=6.662(1),c=8.411(1) Å,=93.00(1),=104.87(1), =105.69(1)°,V _c=270.66(8) ų,Z=1,R=0.0380 for 875 independent observed reflections.     

Crystal structure oftrans-carbonylchlorobis-(tricyclohexylphosphine)iridium(I),trans-Ir(CO)Cl-[P(cyclo-C6H11)3]2, a disordered species

The title compound crystallizes in the centrosymmetric triclinic space group (C ₁ ^l ; No.2) witha=9.9143(10) Å,b=10.2616(11) Å,c=10.7715(10) Å, =113.887(8)°, =109.197(8)°, =90.699(9)°,V=932.78(17) ų andZ=1. A total of 4869 data were collected and merged to a set of 2450 independent reflections; the structure was solved and refined toR=1.42% andwR=1.94%. The molecule lies on a site of symmetry and is disordered, with obvious scrambling of carbonyl and chloride ligands. Resulting bond lengths include Ir–P=2.339(1) Å, Ir–Cl=2.398(4) Å and Ir–CO=1.808(15) Å.     

A reinvestigation of the crystal structure of (4-aminobenzophenone)dichlorocuprate(II) hemiethanolate

The crystal structure of CuCl₂L·1/2 C₂H₅OH has been redetermined, where L=4-aminobenzophenone. C₁₄H₁₄Cl₂CuNO_1.5,M _r=354.5, monoclinic, P2₁/c,a=8.206(1),b=6.196(2),c=29.917 (7) Å, =92.91°,V=1521.8(6) ų,Z=4,D _x=1.55 g cm^–3, (MoK)=0.71069Å, =17.9 cm^–1,F(000)=720,T=295K. The 1984 unique reflections (20<45°), of which 1635 had |F_o|3 (F_o), refined to a finalR of 0.042 andwR=0.049 for the 3 data set. The structure is disordered at room temperature with the ethanol molecules, present at half-occupancy, coordinating to only one half of the Cu(II) ions. The structure is comprised of two types of chains which run parallel tob. One type of chain consists of stacks of CuCl₂L(C₂H₅OH) monomer units, which yield a 4+2 coordination geometry for each Cu atom in the chains. The second type of chains has stacks of binuclear Cu₂Cl₄N₂ species with a 4+1 coordination exhibited by each Cu. The location and orientation of the L ligands appear to be identical in the two stacks. Intermolecular hydrogen bonding between L ligands in adjacent stacks leave space for only one ethanol molecule per two ligands.     

Crystal and molecular structure of chlorotris(triphenylarsine)Cu(1),C54H45As3CuCl

The title compound crystallizes in the monoclinic space groupP2₁/n, witha=28.494(2),b=10.148(5),c=32.172(2) Å,=94.57(1)°, andZ=8 (with two independent molecules in the asymmetric unit). The structure was solved by direct methods and refined by block-diagonal least-squares methods toR=0.057 for 12286 observed reflections. The dimensions and conformations of the two independent molecules are closely similar. The coordination around the copper and arsenic atoms is approximately tetrahedral, although distortion is considerable. Some important mean bond distances and angles with their rms standard deviations are: Cu-Cl=2.270(4), Cu-As=2.419(4), As-C=1.953(2) Å, Cl-Cu-As=105.4(1.2), and As-Cu-As=113.3(8)°.     

X-ray crystal structure oftrans-dichlorobis(2,4,6-collidine)-copper(II)

The X-ray crystal structure oftrans-dichlorobis(2,4,6-collidine)copper(II) has been determined. Dark blue crystals of the complex crystallize in the monoclinic space group P2₁/c, with cell dimensionsa=7.527(3),b=14.732(4),c=7.951(4)Å and=92.79(9)°;V=880.6(6)ų andZ=2. 949 unique reflections withI _net>3(I) on refinement afforded values ofR=0.041 andR _w =0.048.     

X-ray crystal structure oftrans-dichlorobis(2,6-lutidine)palladium(II)

The X-ray structure oftrans-(2,6-lutidine)₂PdCl₂ has been determined. Golden orange crystals of the complex crystallize in the triclinic space group , with cell dimensionsa=7.6950(8),b=7.9705(10),c=8.0485(8)Å, =116.967(9), =113.343(8), and =93.836(9)°;V=385.18(7)ų andZ=2. 1336 unique reflections withI _net>3 (I) on refinement afforded values ofR=0.018 andR _w=0.023.     

Structural characterization of 2,6-bis(N-methylenepiperidino)-4-nitrophenol (MPN) and 2,6-bis-(N-methylenemorpholino)-4-nitrophenol (MMN)3

MPN: C₁₈H₂₇N₃O₃,M _r=333.43, monoclinic,P2₁/n. a=6.207(2),b=21.893(6),c=13.693(3) Å; =96.12(2)^o,V=1850.1(8) ų.,Z=4,D _cal=1.20 mg/m³,F(000)=720, (CuK)=1.5418 Å, andT=298K.R=0.042 andwR=0.049 for 1675 observed reflections. MMN: C₁₆H₂₃N₃O₅,M _r=337.38, triclinic,P,a=9.642(1) Å,b=10.123(5) Å,c=9.341(2) Å, =93.00(3)^o, =90.96(1)^o, =110.46(1)^o, V=852.5(5) ų,D _cal=1.31 mg m^–3.F(000)=360,Z=2, (CuK)=1.5418 Å,R=0.054 andwR=0.074 for 2804 observed reflections. The piperidine and morpholino rings assumechair conformation and orient each other at an angle of 44.8(1)^o (MPN) and 47.1(1)^o (MMN), respectively.Contribution No. 827 from DCB.     

Crystal structure and spectroscopic study oftrans-diaquabis(2-benzoylpyridine)copper(II) nitrate

trans-Diaquabis(2-benzoylpyridine)copper(II) nitrate has been prepared and characterized by spectroscopic methods and X-ray crystallography. The complex exhibits strong infrared carbonyl absorption at 1655 cm^–1 and a broad d-d band centered about 14,090 cm^–1. The crystals are monoclinic, space groupP2₁/c witha=7.872(1),b=14.573(3),c=11.132(1) Å,=102.79(1)°,Z=2, andR _F =0.049 for 2440 observedMo-K reflections. The crystal structure consists of a packing of centrosymmetric [Cu(2-benzoylpyridine)₂(H₂O)₂]²⁺ cations and nitrate ions, which are interlinked by hydrogen bonds to form thick layers corresponding to the (100) family of planes. The coordination geometry about the copper atom is an elongated octahedron with aqua ligands occupying the axial positions. The measured bond distances are: Cu-O(aqua)=2.256(3), Cu-O(L)=2.068(2), and Cu-N=1.965(2) Å.Mr. Wang is on leave from Central Laboratory, Nankai University, Tianjin, China.     

Crystal structure of 1,4,8,12-tetraazacyclopentadecane copper(II) tribromocuprate(I)

The title compound is a mixed valence compound obtained as one of the products of the reaction of Cu(15-ane N₄)Br₂ with CoBr₂·6H₂O in water/acetone solvent (15-ane N₄=1,4,8,12-tetraazacyclopentadecane). The compound is tetragonal, space group P4₂/mbc witha=16.675(2)Å,c=13.185(3)Å,V=3666(1)ų, withZ=8, for p_calc=2.106 g/cc. Refinement of 674 unique observed reflection yielded final values ofR=0.088 andR _w=0.083. The compound contains chains of alternating Cu(15-ane N₄)²⁺ cations and CuBr ₃ ^2– anions. The chains run perpendicular to thec axis, and are arranged in alternate layers running parallel toa andb. The chains lie athwart the mirror planes atz=0 andz=1/2, with disorder observed for both the (15-ane N₄) rings and the CuBr ₃ ^2– anions. The Cu(II) ion is coordinated by the tetradentate macrocycle to yield an approximate square planar coordination. The CuBr ₃ ^2– anions are nearly planar with Cu–Br(ave.)=2.37Å. Long semi-coordinate Cu(II)...Br bonds of 3.0Å link the cations and anions.     

[N(2-ammoniumethyl)piperazinium]tetrachloromono-bromocuprate(II) monohydrate: A compound containing a discrete square-pyramidal unit

The crystal and molecular structure of the [N(2-ammoniumethyl)piperazinium]tetra-chloromonobromocuprate(II) monohydrate is reported. The crystals are monoclinic, space groupP2₁/c,Z=4, witha=9.560(2),b=9.240(3),c=18.270(7)Å,=99.20(2)°. The structure consists of discrete N(2-ammoniumethyl)piperazinium cations, uncoordinated water molecules and [CuCl₄Br]^3– anions, in which four coplanar chlorine atoms occupy the square-basal plane and one bromine atom the axial position, giving the copper(II) ion a moderately elongated square-pyramidal geometry. The structure was refined to a finalR index of 0.0765.     

Crystal and molecular structure of [(C6H5)3Sb]3CuCl·CHC13

The X-ray crystallographic structure determination of [(C₆H₅)₃Sb]₃ Cu(I)Cl·CHC1₃ reveals that the compound crystallizes in the triclinic space groupP¯1 witha=18.827(3),b=14.279(3),c=14.399(3) Å,=84.43,=87.39(2), and=75.18(1)°,V=2734.7(9) ų,Z=2. Least-squares refinement based on 4689 independent observed data [(F _obs)²3(F _obs)²], resulted in a finalR value of 0.064. The cocrystallized solvent molecules were highly disordered. The coordination about Cu(I) of three Sb(C₆H₅)₃ molecules and one Cl ligand is approximately tetrahedral. The Cu-Cl distance, 2.235(5) Å, is extremely short in comparison to previously reported Cu-Cl distances in four-coordinate Cu(I) complexes. In keeping with the short Cu-Cl distance are very long Cu-Sb distances, av. 2.554(5) Å.     

Crystal structure of bis(benzimidazolium) tetrabromocuprate(II)

Stable, dark-violet crystals of (C₇H₇N₂)₂CuBr₄ were obtained from an aqueous solution of CuBr₂, HBr, and benzimidazole. The crystal structure was determined by three-dimensional X-ray analysis. The crystals are monoclinic:C2/c, a=15.651(4),b=7.945(1),c=15.775(4) Å,=91.44(2)°,Z=4,V _c=1960.96 ų,D _x=2.105 g cm^–3. The structure was refined by full-matrix least squares to giveR=0.042 andR _w=0.048 for 1254 intensities above 3(I). The copper(II) ions are four-coordinated in the form of a distorted tetrahedron CuBr₄ ofC ₂ symmetry. Two different Cu-Br bond lengths are observed: Cu-Br(1)=2.426(2), Cu-Br(2)=2.330(2) Å. Only one flattened angle [Br(2)-Cu-Br(2)=132.71(9)°] in the CuBr₄ tetrahedron is noted. The angles Br(1)-Cu-Br(1)=108.83(7), Br(2)-Cu-Br(1)=99.92(5) and Br(2)-Cu-Br(1)=107.13(5)° have been found. Hydrogen bonds explain the deformation of the CuBr ₄ ^2– coordination polyhedron. The structure is compared with other CuX ₄ ^2– complexes.     

Crystal and molecular structure of benzophenone azine: evidence for an Fe(II) carbene intermediate

Benzophenone azine crystallizes in the monoclinic space groupA2/a (No. 15) witha=16.303(3) Å,b=5.4864(2) Å,c=21.973(5) Å, =85.52(2)°,V=1959.4(8) ų, andD _calc=1.22 g cm^–3 forZ=4. The structure was solved by direct methods and refined againstF to a finalR value of 0.047. The unit cell contains four molecules of the title compound; the asymmetric unit consists of half a molecule. Despite the high crystallographic symmetry, the two halves of the molecule arenot related by a center of symmetry; instead, the molecule adopts C₂ symmetry; the molecular C₂ axis is coincident with the crystallographic twofold axis. The formation of benzophenone azine from the reaction of the iron-containing Lewis acid complex [(⁵-C₅H₅)Fe(CO)₂(THF)]⁺ [BF₄]^– and diphenyldiazomethane provides strong evidence for an Fe(II) carbene intermediate.     

Crystal structure of bis-(rhodanine)copper(I) iodide,C6H6CuIN2O2S4

The structure of the polymeric rhodanine compound, C₆H₆CuIN₂O₂S₄, was determined by X-rays.M _r =456.8, monoclinic, space groupP2₁/c,a=4.1947(7),b=17.6999(12),c=17.1048(8) Å,=96.15(1)°,V _c =1262.6 ų,Z=4,D _c =2.40Mg m^–3, CuK radiation (graphite crystal monochromator, =1.54056 Å),(CuK)=278.9 cm^s-1,F(000)=872,T=290 K. Final conventionalR-factor=0.029, andR _w =0.044 for 2384 unique reflections and 153 variables. The structure was solved using Patterson methods andDirdif, and refined by full-matrix least-squares methods. The compound forms zigzag chains alonga. The copper atom is in trigonal pyramidal coordination, with two sulfur atoms of the thiocarbonyl group and two bridging iodine atoms. The copper-sulfur distances are 2.278(1) and 2.299(1) Å, and the copper-iodine distances are 2.657(1) and 2.814(1) Å.     

Crystallographic and IR spectral study ofcis-bis(creatinine-N)dinitro platinum(II)

Acis-Pt(creat)₂(NO₂)₂ complex was synthesized stereoselectively in a high yield (65%) and characterized by IR spectral and X-ray diffraction analysis. Crystal data: Pt(C₄H₇N₃O)₂(NO₂)₂,M _r=767.55, monoclinic, space groupP2₁/n,a=9.736(1),b=13.433(1),c=12.098(1) Å,=110.55(1)°,V _c=1482(1) ų,Z=2,D _x=3.441 g cm^–3,(MoK)=0.71073 Å,=97.0 cm^–1,F(000)=1504,T=292 K,R=0.026 andR _w=0.028 for 2061 observed reflections with I>2(I). The structure consists of Pt(creat)₂(NO₂)₂ molecules disposed in general positions and joined by N-HO and N-HN hydrogen bonds. The platinum atom has square-planar PtN₄ coordination of twocis disposed pairs of nitro [Pt-N_av 2.023(7) Å] and creatinine [Pt-N(endo)_av 1.991(8) Å] ligands. The creatinine moieties are planar and tilted to the equatorial plane by ~80°.     

N,N′-(1,2-phenylene)bis(pyridoxal-hydrochlorideiminato)copper(II): crystallographic and spectroscopic studies

(C₂₂H₂₂CuN₄O₄Cl_{2 2}·7H₂O is triclinic,C _i– ¹ t-P1. Unit cell dimensions at 293 K area=12.028(3),b=20.378(6),c=11.387(3) Å, =113.10(2),=84.13(2), =95.99(2)°,V=2547.5 0A³,D _c =1.573 Mg. m^–3, andZ=2. The structure has been determined from single-crystal data collected with a four-circle diffractometer and refined from 3904 reflections down toR=0.054 andR _w =0.058. The asymmetric unit is built from two independent A and B molecules in which the copper atom has a square pyramidal environment in A and an octahedral one inB. Intermolecular Cu-O (hydroxymethyl groups) contacts observed in the solid state are partially present in aqueous solutions.     

Synthesis,spectroscopic characterization of thiosemicarbazone complexes of nickel(II) and X-ray structures of anisaldehyde thiosemicarbazone (ATSZH) and bis(tolualdehyde thiosemicarbazonato)nickel(II)

Complexes of nickel(II) with anisaldehyde (ATSZH), tolualdehyde (TTSZH), and vanillin (VTSZH) thiosemicarbazones have been synthesized and characterized by means of UV-Visible, I.R., Raman,¹H and¹³C NMR spectroscopy. The thiosemicarbazones have been found to exist in the thione form.¹H and¹³C NMR as well as electronic spectral data support a square planar structure for Ni(ATSZ)₂ and Ni(TTSZ)₂ complexes.¹H and¹³C NMR spectra indicate that the structure of Ni(VTSZ)₂ complex differs from the other two nickel(II) complexes and it may possibly consist of mixtures of isomers. The X-ray structures of Ni(TTSZ)₂ and ATSZH were determined: the nickel complex is monoclinic witha=26.412(6),b=12.135(3),c=6.888(1)Å,=95.41(5)°,Z=4,R=0.0647, space groupC2/c. The structure consists of discrete Ni(TTSZ)₂ molecules in which the metal, located on a symmetry centre, is N,S-chelated by two ligands forming two five-term chelate rings. The structure of ATSZH is also monoclinic:a=7.859(1),b=13.481(3),c=10.028(3) Å,=106.32(4)°,Z=4,R=0.0412, space groupP2₁/c. The molecules, connected by NO hydrogen bonds, reveal a considerable tilting of the aromatic ring in respect to the thiourea moiety if compared with the nickel structure.     

A palladium(II) complex of a tetradentate amine-phenol ligand

A palladium(II) complex of an amine-phenol ligand N,N-bis(2-hydroxybenzyl)1,4-diaminobutane has been synthesized and characterized by NMR, IR, and X-ray diffraction studies. Diffraction data were collected with a Nonius CAD-4 diffractometer with -2 scan and MoK radiation. The structure was solved by conventional methods resulting in anR factor of 0.022 for 1058 independent reflections. The X-ray structure shows a discrete mononuclear square planar complex in which the Pd is coordinated to the two nitrogens and two oxygens of the ligand. The complex is neutral with the Pd(II) charge balanced by deprotonation of both phenolic oxygens. Crystal data: Space group Pna2₁,a+8.223 Å,b+22.477 Å,c+9.190 Å;V+1698.8 ų;Z+4.     

Crystal and molecular structures of trans-bis(acetonitrile)bis(bipyridine)ruthenium(II) perchlorate and trans-diamminebis(bipyridine)ruthenium(II) perchlorate

The structures of trans-[(MeCN)₂(bpy)₂Ru](ClO₄)₂(I) andtrans-[(NH₃)₂(bpy)₂Ru](ClO₄)₂(II) have been determined by single crystal X-ray diffraction methods. (I) forms monoclinic crystals in the space groupP2₁/c witha=8.399(2),b=10.406(2),c=15.590(3) Å,=93.78(2)° andZ=2 atT=293 K. The final refinement gaveR=0.040 for 2448 reflections withF _o ² >3(F _o ² ). (II) crystallizes in the triclinic space groupP¯1 witha=1.702(1),b=8.439(2),c=10.525(2) Å,=107.56(2),=104.63(1), =100.89(2)° andZ=1 atT=293 K. Refinement using 1878 reflections withF _o ² >3(F _o ² ) produced a finalR value of 0.036. Both of these structures have the ruthenium atom located on a crystallographic inversion center. The bipyridine ligands in both structures are in the bowed conformation as a means of circumventing the steric problems associated with the trans arrangement of the bipyridine ligands. The Ru-N(monodentate) distance is longer for the ammonia complex (2.106(3) Å) than for the acetonitrile complex (2.008(4) Å); there are no significant differences in the distances and angles of the two Ru(bpy)₂ frameworks.     

Synthesis and characterization of taurine Schiff base derivatives and their Cu(II) complexes: Crystal and molecular structure of 5-NO2 salicylaldimine ethylene sulfonic acid complex of Cu(II)

Spectroscopic analysis of eight copper(II) complexes of Schiff bases derived from taurine and eight different salicylaldehydes and naphthaldehydes are reported. X-ray structural analysis of the copper(II) complex of the 5-NO₂-sali-cylaldehyde imine of taurine (5-NO₂-salicylaldimine ethylene sulfonic acid) as the tetran-butylammonium salt [Cu(C₉H₈N₂O₆S)₂]^2–2[(C₄H₉)₄N]⁺ (CUTAU-TBA) has been carried out. The space group isP¯1, witha=8.761(4),b=10.410(3),c=16.528(4) Å,=77.85(3),=86.53(4), =79.15(3)°, andZ=1. The structure was solved by the heavy-atom method and refined by least-squares techniques to anR factor of 0.068 for 2807 observed reflections. The CUTAU cation is centrosymmetric, with the Cu atom sitting on a crystal-lographic centre of symmetry. The copper atom has a square-planar environment, coordinated by the potentially tridentate Schiff base only through the imino nitrogen and the phenolate oxygen with the deprotonated sulfonic group directed away from the coordination sphere of the Cu(II).