Komplexe zweier vierzehngliedriger Tetraazadibenzo-Makrocyclen. Strukturen eines freien Liganden und von Nickel(II)-, Kupfer(II)- und Zink(II)-Komplexen / Complexes of Two 14-Membered N4 Dibenzo Macrocycles. Crystal Structures of a Free Ligand and of Nickel(II), Copper(II) and Zinc(II) Complexes

1999 ◽  
Vol 54 (3) ◽  
pp. 321-328 ◽  
Author(s):  
Rainer Mattes ◽  
Ulrich Voet

The syntheses and structural characterizations of complexes of two 14-membered macrocyclic trans-N4 dibenzo ligands, 5,7,8,9,14,16,17,18-octahydrodibenzo[e,1]-[1,4,8,11-tetraazacyclotetradecine- 6,15-dimethyl (L3) resp. -6,15-diacetamide (L4), are presented. The crystal structures of five compounds have been determined by single crystal X-ray diffraction. The free ligand L3 has a saddle-shaped structure with intramolecular hydrogen bonds. This conformation of the ligand exists also in the Zn(II) complex in which the metal ion is five-coordinated with the metal center outside the cavity. The coordination polyhedron is intermediate between a trigonal bipyramid and a square pyramid. In cis-[Ni(L3)(NCS)2] the ligand is folded along an N ⋯ N axis. The nickel ion in this complex shows an approximate octahedral geometry. For Ni(II) and Cu(II) complexes of ligand L the overall geometry is also distorted octahedral. The folding of the ligand causes a cis-N4O2 coordination.

1998 ◽  
Vol 53 (8) ◽  
pp. 836-840 ◽  
Author(s):  
Vladimir A. Ovchynnikov ◽  
Vladimir M. Amirkhanov ◽  
Anatoliy A. Kapshuk ◽  
Tatyana Yu. Sliva ◽  
Tadeusz Glowiak ◽  
...  

Abstract A new nickel(II) complex with N,N′-tetraethyl-N″-benzoylphosphortriamide (HL = C6H5C(O)N(H)P(O)(NEt2)2) of composition Ni4L4(OCH3)4·(HOCH3)4 (1) has been synthe­ sized. The crystal and molecular structure of 1 has been determined from the X-Ray diffraction data (tetragonal, space group P4̄21c with a = 17.000(2) Å, c = 15.338(3) Å, Z = 2; R = 0.0399 for 1412 unique reflections). The structure is made up of cubane-like tetramers. In the corners of a cube there are 4 atoms of nickel and 4 atoms of oxygen of methoxy groups. The nickel atoms are characterized by a slightly distorted octahedral environment, which consists of three oxygen atoms of methoxy groups, carbonylic and phosphorylic oxygen atoms of the ligand L-, and an oxygen atom of a methanol molecule. The ligands L- coordinate to the metal ion forming a chelate via the oxygen atoms of carbonylic and phosphorylic groups.


2006 ◽  
Vol 61 (10) ◽  
pp. 1217-1221 ◽  
Author(s):  
Zerrin Heren ◽  
Cem Keser ◽  
C. Cüneyt Ersanli ◽  
O. Zafer Yeşilel ◽  
Nazan Ocak

The mixed-ligand picolinato (pic) complex of Cu(II) with 4-methylimidazole (4-MeIm), [Cu(pic)2(4-MeIm)2], was synthesized and characterized by elemental analysis, magnetic susceptibility, spectroscopic methods (UV/vis and FT-IR) and X-ray diffraction. In the slightly distorted octahedral cis-bis(4-methylimidazole)bis(picolinato)copper(II) complex, the pic ligands are coordinated to the Cu(II) ion as bidentate N,O-donors forming chelate rings. The 4-MeIm ligands are N-coordinated in cis positions. The complex crystallizes in the triclinic space group p̅1 with unit cell parameters a = 9.204(5), b = 9.498(5), c = 13.095(5) Å , α = 90.395(5), β = 101.687(5), γ = 112.291(5)° and Z = 2. Hydrogen bondings and C-H ··· π interactions occur between picolinato and methylimidazole ligands of neighboring complex molecules. The thermal decomposition of the complex is described.


1982 ◽  
Vol 37 (7) ◽  
pp. 863-871 ◽  
Author(s):  
William S. Sheldrick

AbstractThe stable ternary copper(II) complexes of ATP and ADP, [Cu(H2ATP)(phen)]2 · 7 H2O (2) and [Cu4(HADP)2(bipy)4(H2O)2(NO3)2] · 2 NO3 (3), have been isolated from aqueous solution at respective pH values of 2.8 and 4.0. Their structures have been established by single crystal X-ray diffraction. Tridentate coordination of each of the Cu atoms by ono α-, one β- and one γ-phosphate O atom of one ATP molecule is observed in 2. The binding Oα atoms occupy axial positions in a distorted octahedral geometry at Cu and the Cu- Oα interactions are weak. The other axial position is occupied by a γ-phosphate O atom of the second ATP molecule, leading to a dimeric structure. The basic structure of 3 is similar with, in this case, bidentate coordination of each of the central Cu atoms by one α- and one β-phosphate O atom of ono ADP molecule. In this case, however, the third terminal β-phosphate O atoms each bind a further Cu atom. All four Cu atoms in 3 display square pyramidal coordination. The structures of 2 and 3 are stabilised by intramolecular stacking of adenine and phenanthroline/bipyridyl systems. The significance of these structures as models for enzyme-metal ion-nucleoside polyphosphate complexes is discussed.


1998 ◽  
Vol 51 (9) ◽  
pp. 835 ◽  
Author(s):  
Peter Turner ◽  
Maxwell J. Gunter ◽  
Brian W. Skelton ◽  
Allan H. White

The room-temperature single-crystal X-ray diffraction determined structures of the Mn(tpp)Br.C7H8, Mn(tpp)(NCO), Mn(tpp)I.C7H8, Mn(tpp)(CO2CH3).0·5C7H8, and Mn(tpp)(NCS).0·5C7H8 complexs are described. The monoclinic P21/c unit cell of Mn(tpp)(NCO) has a 14·82(1), b 17·136(5), c 14·576(5) Å, β 111·41(5)°, V 3446(3) Å3, Z 4. The refinement converged with conventional R(|F|) 0·053 for No 3199 (I > 3·0σ(I)) ‘observed’ reflections. The monoclinic P 21/m unit cell of Mn(tpp)Br.C7H8 has a 9·984(1), b 15·453(6), c 13·583(3) Å, β 103·99(2)°, V 2033(1) Å3, Z 2, R 0·039 for No 2668. The Mn(tpp)I.C7H8 structure is triclinic, P-1, with a 22·28(1), b 14·466(4), c 13·555(6) Å, α 76·32(3), β 81·74(4), γ 74·75(3)°, V 4079(3) Å3, Z 4, R 0·050 for No 9039. The triclinic P-1 crystal structures of the Mn(tpp)(CO2CH3).0·5C7H8 and Mn(tpp)(NCS).0·5C7H8 complexes are isomorphous. The Mn(tpp)(CO2CH3).0·5C7H8 structure has a 26·18(1), b 13·503(3), c 12·074(6) Å, α 66·08(4), β 81·36(4), γ 86·71(5)°, V 3858(3) Å3, Z 4, R 0·075 for No 6388. Solvate disorder, requiring a rigid body model, islargely responsible for the relatively high residuals. The Mn(tpp)(NCS).0·5C7H8 structure has a 25·442(6), b 13·746(3), c 12·182(5) Å, α 66·97(3), β 78·59(3), γ 87·90(2)°, V 3839(2) Å3, Z 4, R 0·061 for No 5506. The asymmetric units of the iodo, acetato and isothiocyanato structures each contain two crystallographically independent complex molecules that are sensitive to crystal packing forces. The metal ion displacements from the least-squares planes formed by the pyrrole nitrogen atoms are 0·299(1) and 0·274(1) Å for the Mn(tpp)(NCO) and Mn(tpp)Br.C7H8complexes, and 0·240(1) and 0·252(1), 0·281(1) and 0·278(1), and 0·243(1) and 0·244(1) Å for the independent (a) and (b) complex molecules of Mn(tpp)I.C7H8, Mn(tpp)(CO2CH3).0·5C7H8, and Mn(tpp)(NCS).0·5C7H8 respectively. The axial Mn–X bond lengths are 2·029(5) and 2·490(1) Å for the Mn(tpp)(NCO) and Mn(tpp)Br.C7H8 complexes, and 2·767(1) and 2·730(1), 2·028(5) and 2·010(5), and 2·067(6) and 2·072(5) Å for the (a) and (b) complex molecules of Mn(tpp)I.C7H8, Mn(tpp)(CO2CH3).0·5C7H8, and Mn(tpp)(NCS).0·5C7H8. One of the independent complex molecules in the Mn(tpp)(CO2CH3).0·5C7H8 structure appears to exhibit acetate coordination through a carbonyl oxygen.


2000 ◽  
Vol 56 (3) ◽  
pp. 438-443 ◽  
Author(s):  
Brian N. Figgis ◽  
Alexandre N. Sobolev ◽  
Charles J. Simmons ◽  
Michael A. Hitchman ◽  
Horst Stratemeier ◽  
...  

The crystal structures of the Tutton salts (NH4)2-[Cu(H2O)6](SO4)2, diammonium hexaaquacopper disulfate, formed with normal water and isotopically substituted H2 18O, have been determined by X-ray diffraction at 9.5 K and are very similar, with Cu—O(7) the longest of the Cu—O bonds of the Jahn–Teller distorted octahedral [Cu(H2O)6]2+ complex. It is known that structural differences accompany deuteration of (NH4)2[Cu(H2O)6](SO4)2, the most dramatic of which is a switch to Cu—O(8) as the longest such bond. The present result suggests that the structural differences are associated with hydrogen-bonding effects rather than with increased mass of the water ligands affecting the Jahn–Teller coupling. The Jahn–Teller distortions and hydrogen-bonding contacts in the compounds are compared with those reported for other Tutton salts at ambient and high pressure.


1983 ◽  
Vol 38 (12) ◽  
pp. 1615-1621 ◽  
Author(s):  
Annegret Lipka

2,2′-Bipyridinium pentachloroantimonate (III) and the metastable modification of 4,4′-bipyridinium pentachloroantimonate(III) were synthezised and investigated by single crystal X-ray diffraction analysis. The structures consist of 2,2′-bipyridinium and 4,4′-bipyridinium cations, respectively, and of pentachloroantimonate anions. With regard to bonding and short intermolecular contacts the coordination of the Sb atoms is distorted octahedral in both structures. Bond lengths of equivalent Sb-Cl bonds differ strongly within the structure of the 2,2′-bipyridinium salt (239.9 pm to 312.1 pm) and are not distinguishable from short intermolecular contacts (305.4 pm and 321.8 pm). In the structure of the 4,4′-bipyridinium salt, bond distances vary only from 240.9 pm to 267.8 pm and are clearly below intermolecular contacts at 318.2 pm. In spite of the different distances the total bond order for each Sb atom is 3. In the structure of the 2,2′-bipyridinium salt the anions build tetramers, whereas in the structure of the 4,4′-bipyridinium salt the anions form chains


2007 ◽  
Vol 72 (5-6) ◽  
pp. 649-665 ◽  
Author(s):  
M. Fernanda N. N. Carvalho ◽  
Ana S. D. Ferreira ◽  
João L. Ferreira da Silva ◽  
Luís F. Veiros

3-Hydrazonocamphor, 3-(RR1NN)C10H14O (R = Me, R1 = H), undergoes intramolecular hydrogen bridging by coordination to platinum or palladium. This effect is evidenced by considerable decrease in the ν(C=O) frequency (compared to the free ligand) in the IR spectra of the complexes [MCl2L2] (M = Pd, Pt; L = 3-(RR1NN)C10H14O) as well as by the magnetic non- equivalence of the two ligands, as revealed by 13C NMR. DFT calculations indicate that coordination of 3-(Me(H)NN)C10H14O promotes E/Z isomerization of the hydrazono group of the ligand, inducing formation of intramolecular hydrogen bonding and corresponding stabilization of the complex. Characterization of the complexes [MCl2L2] (M = Pt; L: R, R1 = Me (1), R = Me, R1 = H (2) and M = Pd; L: R = Me, R1 = H (3)) was performed by analytical and spectroscopic techniques. Redox properties of the 3-hydazonocamphors and their complexes were studied by cyclic voltammetry. The structure of trans-[PtCl2{3-(Me2NN)C10H14O}2] was determined by single-crystal X-ray diffraction analysis. The complex has square-planar geometry and crystallizes in the tetragonal P43 space group.


1996 ◽  
Vol 51 (6) ◽  
pp. 869-878 ◽  
Author(s):  
Ralf Feldhaus ◽  
Jens Köppe ◽  
Rainer Mattes

Abstract The synthesis and structural characterisation of complexes of the 14-membered macrocyclic trans-N4 dibenzo ligand 5,6,7,8,9,14.15,16,17,18-decahydrodibenzo[e,l][1,4, 8,11]-tetraazacyclotetradecine (L2) is described. The crystal structures of six compounds were determined by single crystal X-ray diffraction. The free ligand L2 has a saddle-shaped structure with short intramolecular hydrogen bonds. The N-N distances are 289 pm. The diprotonated species [H2L2]2+ has a different conformation due to intra- and intermolecular hydrogen bonds. The ligand is folded along an N-N axis in c/s-[Ni(L2)(H2O)2]2+, but displays a saddleshaped structure in the Cu(II), Zn(II) and Pd(II) complexes with a more or less planar arrangement of the four N donor atoms. The metal atoms are incorporated within the macrocyclic cavity in [Cu(L2)(CF3SO3)]+ and [Pd(L2)]2+. The metal-to-nitrogen bond lengths herein are rather small. Zn(II) is five-coordinate in [Zn(L2)(Cl)]+. The coordination polyhedron is intermediate between a trigonal bipyramid and a square pyramid. In all complexes the metalto- ligand distances originating at the nitrogen atoms in β-position (with respect to the aromatic ring) are significantly shorter then the donor bonds of the ‘anilinic’ N atoms


2012 ◽  
Vol 2012 ◽  
pp. 1-6
Author(s):  
Ling-Ling Gao ◽  
Yan Liu ◽  
Xu-Yan Lv ◽  
Jian-Feng Liu ◽  
Tuo-Ping Hu

Templated coordination polymers [Ni(H2O)4(bipy)](BTA)0.5·H2O (1) and [Co(H2O)4(bipy)](BTA)0.5·H2O (2) (bipy = 4,4′-Bipyridine, H4BTA = 1,2,4,5-Benzenetetracarboxylic Acid) were synthesized and characterized by single-crystal X-ray diffraction, powder diffraction, elemental analysis, IR, and thermogravimetric analysis. Both of complexes 1 and 2 are monoclinic crystal system, C2/c space group, and isostructural. The unit of the structure, the metal ion is coordinated by four water molecules and two bipy molecules, is a slightly distorted octahedral configuration, and the carboxyl group from BTA4- ion doesn't coordinate with the metal ion, the H-bonding interactions further connect the mononuclear molecules to generate a 3D supramolecular complex.


2018 ◽  
Vol 74 (7) ◽  
pp. 782-788 ◽  
Author(s):  
Ewa Żesławska ◽  
Wojciech Nitek ◽  
Henryk Marona ◽  
Agnieszka Gunia-Krzyżak

A number of cinnamamide derivatives possess anticonvulsant activity due to the presence of a number of important pharmacophore elements in their structures. In order to study the correlations between anticonvulsant activity and molecular structure, the crystal structures of three new cinnamamide derivatives with proven anticonvulsant activity were determined by X-ray diffraction, namely (R,S)-(2E)-N-(2-hydroxybutyl)-3-phenylprop-2-enamide–water (3/1), C13H17NO2·0.33H2O, (1), (2E)-N-(1-hydroxy-2-methylpropan-2-yl)-3-phenylprop-2-enamide, C13H17NO2, (2), and (R,S)-(2E)-N-(1-hydroxy-3-methyl-butan-2-yl)-3-phenylprop-2-enamide, C14H19NO2, (3). Compound (1) crystallizes in the space group P\overline{1} with three molecules in the asymmetric unit, whereas compounds (2) and (3) crystallize in the space group P21/c with one and two molecules, respectively, in their asymmetric units. The carbonyl group of (2) is engaged in an intramolecular hydrogen bond with the hydroxy group. This type of interaction is observed for the first time in these kinds of derivatives. A disorder of the substituent at the N atom occurs in the crystal structures of (2) and (3). The crystal packing of all three structures is dominated by a network of O—H...O and N—H...O hydrogen bonds, and leads to the formation of chains and/or rings. Furthermore, the crystal structures are stabilized by numerous C—H...O contacts. We analyzed the molecular structures and intermolecular interactions in order to propose a pharmacophore model for cinnamamide derivatives.


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