scholarly journals A new compound in the BEDT-TTF family [BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene] with a tetrathiocyanatocuprate(II) anion, (BEDT-TTF)4[Cu(NCS)4]

2018 ◽  
Vol 74 (12) ◽  
pp. 1755-1758 ◽  
Author(s):  
Christophe Faulmann ◽  
Benoît Cormary ◽  
Lydie Valade ◽  
Kane Jacob ◽  
Dominique de Caro

A new phase combining BEDT-TTF and [Cu(NCS)4]2– as the counter-anion, namely bis[bis(ethylenedithio)tetrathiafulvalenium] tetrathiocyanatocuprate(II) bis[bis(ethylenedithio)tetrathiafulvalene], (C10H8S8)2[Cu(NCS)4]·2C10H8S8 or (BEDT-TTF)4[Cu(NCS)4] was obtained during a galvanostatic electrocrystallization process. As previously observed with BEDT-TTF-based compounds with oxalatometallate anions, the BEDT-TTF molecules in (BEDT-TTF)4[Cu(NCS)4] exhibit the so-called pseudo-κ arrangement, with two BEDT-TTF molecules being positively charged and two electronically neutral. The bond lengths and angles in the two unique BEDT-TTF molecules differ slightly. The crystal structure consists of layers of BEDT-TTF molecules extending parallel to (001). The width of this layer corresponds to the length of the a axis [16.9036 (17) Å]. The BEDT-TTF layers are separated by layers of centrosymmetric square-planar [Cu(NCS)4]2– dianions.

Author(s):  
Amalina Mohd Tajuddin ◽  
Hadariah Bahron ◽  
Hamizah Mohd Zaki ◽  
Karimah Kassim ◽  
Suchada Chantrapromma

The asymmetric unit of the title complex, [Pd(C15H13FNO)2], contains one half of the molecule with the PdIIcation lying on an inversion centre and is coordinated by the bidentate Schiff base anion. The geometry around the cationic PdIIcentre is distorted square planar, chelated by the imine N- and phenolate O-donor atoms of the two Schiff base ligands. The N- and O-donor atoms of the two ligands are mutuallytrans, with Pd—N and Pd—O bond lengths of 2.028 (2) and 1.9770 (18) Å, respectively. The fluorophenyl ring is tilted away from the coordination plane and makes a dihedral angle of 66.2 (2)° with the phenolate ring. In the crystal, molecules are linked into chains along the [101] direction by weak C—H...O hydrogen bonds. Weak π–π interactions with centroid–centroid distances of 4.079 (2) Å stack the molecules alongc.


2020 ◽  
Vol 76 (12) ◽  
pp. 1813-1817
Author(s):  
Masatoshi Mori ◽  
Takayoshi Suzuki

The crystal structures of the complexes (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]nickel(II) bis(perchlorate) nitromethane monosolvate, [Ni(C11H12NP)2](ClO4)2·CH3NO2 (1), and (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]platinum(II) bis(tetrafluoroborate) acetonitrile monosolvate, [Pt(C11H12NP)2](BF4)2·C2H3N (2), are reported. In both complex cations, two phosphanylquinolines act as bidentate P,N-donating chelate ligands and form the mutually cis configuration in the square-planar coordination geometry. The strong trans influence of the dimethylphosphanyl donor group is confirmed by the Ni—N bond lengths in 1, 1.970 (2) and 1.982 (2) Å and, the Pt—N bond lengths of 2, 2.123 (4) and 2.132 (4) Å, which are relatively long as compared to those in the analogous 8-(diphenylphosphanyl)quinoline complexes. Mutually cis-positioned quinoline donor groups would give a severe steric hindrance between their ortho-H atoms. In order to reduce such a steric congestion, the NiII complex in 1 shows a tetrahedral distortion of the coordination geometry, as parameterized by τ4 = 0.199 (1)°, while the PtII complex in 2 exhibits a typical square-planar coordination geometry [τ4 = 0.014 (1)°] with a large bending deformation of the ideally planar Me2Pqn chelate planes. In the crystal structure of 2, three F atoms of one of the BF4 − anions are disordered over two sets of positions with refined occupancies of 0.573 (10) and 0.427 (10).


1983 ◽  
Vol 61 (6) ◽  
pp. 1132-1141 ◽  
Author(s):  
Gordon William Bushnell ◽  
Roderick James Densmore ◽  
Keith Roger Dixon ◽  
Arthur Charles Ralfs

Synthesis and 31P nmr spectra of the complex cations, cis-[PtCl(L)(PEt3)2]+, L= theophylline, caffeine, or isocaffeine, and cis[Pt(isocaff)2(PEt3)2]2+ are reported. The crystal structure of cis-[PtCl(caffeine)(PEt3)2][BF4] is determined, space group [Formula: see text], a = 1.1766(6), b = 1.4428(5), c = 0.9002(4) nm, α = 97.28(4)°, β = 97.69(4)°, γ = 100.96(5)°, Dm = 1.649 g cm−1, the bond lengths are Pt—Cl= 233.4(4) pm, Pt—N = 215(1) pm, Pt—P = 225.4(5) pm (mean), and the residual R = 0.071. The crystal structure of cis-[Pt(isocaffeine)2(PEt3)2][BF4]2 is orthorhombic, space group Pbca, a = 2.317(3), b = 1.717(3), c = 2.130(3) nm, Dm = 1.574 g cm−3, with an opposing isocaffeine conformation, bond lengths Pt—N = 211(2) pm, Pt—P = 227.6(9) pm (mean), and R = 0.073. Both crystal structures contain approximately square planar Pt(II) coordination with the purine coordinated via an imidazole nitrogen. The structures are discussed as models for the possible involvement of [Formula: see text] chelation of guanine to platinum when platinum drugs act as antitumour agents, but there is no evidence that isocaffeine acts as an [Formula: see text] chelate.


2017 ◽  
Vol 232 (5) ◽  
pp. 339-347 ◽  
Author(s):  
Zoran Mazej ◽  
Evgeny Goreshnik

AbstractThe [Ag(H2O)2]SbF6, is triclinic, P1̅ (No. 2), with a=6.6419(3) Å, b=7.6327(3) Å, c=11.1338(3) Å, α=95.492(3)°, β=96.994(3)°, γ=113.535(4)°, V=507.13(4) Å3 at 150 K, and Z=3. There are two crystallographically non-equivalent Ag+ cations. The Ag1 is coordinated by two water molecules with Ag–OH2 distances equal to 2.271(2) Å forming in that way a discrete linear [Ag(H2O)2]+ cation. Additionaly, it forms two short Ag···F contacts (2.630(2) Å), resulting in AgO2F2 plaquette, and four long ones (2×3.001(2) Å and 2×3.095(2) Å) with fluorine atoms located below and above the AgO2F2 plaquette. The H2O molecules bridge Ag2 atoms into {–[Ag(μ-OH2)2]–}n infinite chains, with Ag–O distances of 2.367(2)–2.466(2) Å. The [Pd(H2O)4](SbF6)2·4H2O is monoclinic, P21/a (No.14), with a=8.172(2) Å, b=13.202(3) Å, c=8.188(3) Å, β=115.10(1)o, V=799.9(4) Å3 at 200 K, and Z=2. Its crystal structure can be described as an alternation of layers of [Pd(H2O)4]2+ cations (interconnected by H2O molecules) and [SbF6]− anions. It represents the first example where [Pd(H2O)4]2+ has been structurally determined in the solid state. Four oxygen atoms provided by H2O molecules are in almost ideal square-planar arrangement with Pd–O bond lengths 2×2.004(5) Å and 2×2.022(6) Å. The [Cd(H2O)6](SbF6)2, is orthorhombic, Pnnm (No.58), with a=5.5331(2) Å, b=14.5206(4) Å, c=8.9051(3) Å, V=715.47(4) Å3 at 200 K, and Z=2. It consists of [Cd(H2O)6]2+ cations and [SbF6]− anions.


2020 ◽  
Vol 76 (11) ◽  
pp. 1725-1727
Author(s):  
Volodymyr Levchenko ◽  
Sigurd Øien-Ødegaard ◽  
David Wragg ◽  
Mats Tilset

The title compound, an (N^C)-cyclometalated gold(III) diazide, namely, diazido[5-ethoxycarbonyl-2-(5-ethoxycarbonylpyridin-2-yl)phenyl-κ2 C 1,N]gold(III), [Au(C17H16NO4)(N3)2] or Au(ppyEt)(N3)2, was synthesized by reacting Au(ppyEt)Cl2 with NaN3 in water for 24 h. The complex has been structurally characterized and features a gold center with a square-planar environment. The Au—N(azide) bond lengths are significantly different depending on the influence of the atom trans to the azide group [Au—N(trans to C) of 2.067 (2) Å versus Au—N(trans to N) of 2.042 (2) Å]. The azide groups are twisted in-and-out of plane by 56.2 (2)°.


Author(s):  
Patrick O'Brien ◽  
Matthias Zeller ◽  
Wei-Tsung Lee

The title compound, [NiBr(C25H29N2O)], contains an NiII atom with a slightly distorted square-planar coordination environment defined by one O and two N atoms from the 2-{[(8-aminonaphthalen-1-yl)imino]methyl}-4,6-di-tert-butylphenolate ligand and a bromide anion. The Ni—O and Ni—N bond lengths are slightly longer than those observed in the phenyl backbone counterpart, which can be attributed to the larger steric hindrance of the naphthyl group in the structure of the title compound. The molecule as a whole is substantially distorted, with both the planar naphthalene-1,8-diamine and imino–methyl–phenolate substitutents rotated against the NiN2OBr plane by 38.92 (7) and 37.22 (8)°, respectively, giving the molecule a twisted appearance. N—H...Br hydrogen bonds and N—H...C(π) contacts connect the molecules into dimers, and additional C—H...Br contacts, C—H...π interactions, and an offset stacking interaction between naphthyl units interconnect these dimers into a three-dimensional network.


2019 ◽  
Vol 74 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Ralf Albrecht ◽  
Phil Liebing ◽  
Uwe Morgenstern ◽  
Christoph Wagner ◽  
Kurt Merzweiler

AbstractThioether-functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with R=Me, Ph and R′=t-Bu, Me, Ph were synthesized from the corresponding dichlorosilanes R2SiCl2 and lithiated aniline derivatives LiNH-C6H4-2-SR′. Treatment of the functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with two eq. of n-BuLi and subsequent reaction with nickel(II) halides NiX2 (X=Cl, Br) or [Ni(acac)2(TMEDA)] led to the formation of the Ni(II) complexes [Ni{R2Si(N-C6H4-2-SR′)2}]. The X-ray single-crystal structure determinations of the nickel complexes revealed that the thioether-functionalized silylamides R2Si(NC6H4-2-SR′)22− act as tetradentate ligands. The nickel atoms exhibit a distorted square-planar coordination with Ni–N and Ni–S bond lengths in the range of 186.4(3)–186.9(2) pm and 217.5(1)–221.5(1) pm, respectively.


2018 ◽  
Vol 74 (9) ◽  
pp. 1369-1372 ◽  
Author(s):  
Christopher A. Dodds ◽  
Alan R. Kennedy

The crystal structure of bis[μ-(1,3-dimesityl-1H-imidazol-3-ium-2-yl)methanolato-κ2 O:O]bis[dichloridocopper(II)], [Cu2Cl4(C22H26N2O)2], is reported. The complex is assumed to have formed via the insertion of formaldehyde into the copper–carbon bond in an N-heterocyclic carbene complex of copper(I) chloride. The structure of the binuclear molecule possesses a crystallographically centrosymmetric Cu2O2 central core with the O atoms bridging between the CuII atoms and thus Z′ = 0.5. The copper centres are further ligated by two chloride ligands, resulting in the CuII atoms residing in a distorted square-planar environment. The Cu—O bond lengths are shorter than those previously reported in structures with the same central Cu2O2 motif. The complex displays C—H...Cl interactions involving the H atoms of the heterocycle backbone and the chloride ligands of a neighbouring molecule.


1976 ◽  
Vol 31 (5) ◽  
pp. 554-557 ◽  
Author(s):  
Martin Weishaupt ◽  
Joachim Strähle

[Au(NH3)4](NO3)3 crystallizes in the orthorhombic space group Cmmm, α = 7.243, b = 13:805, c = 5.302 Å, Z = 2. The crystal structure is built up by NO3- anions and square planar [Au(NH3)4]3+ cations with Au-N bond lengths of 2.02 A. The vibrational spectra of the compound are discussed.


Author(s):  
Ali Ourari ◽  
Chahinaz Zoubeidi ◽  
Sofiane Bouacida ◽  
Wassila Derafa ◽  
Hocine Merazig

In the title compound, [Cu(C10H11BrNO)2], the asymmetric unit consists of one-half of the molecule, the other half being generated by an inversion centre. Hence the CuIIcation is symmetrically coordinated by two bidentate Schiff base anions in a slightly distorted square-planar environment with Cu—O and Cu—N bond lengths of 1.8786 (19) and 2.009 (2) Å, respectively. In the crystal, individual molecules are packed in alternating zigzag layers parallel to (001). Weak C—H...π interactions exist between the molecules.


Sign in / Sign up

Export Citation Format

Share Document