Structural Characterization of Encapsulation Reactions Based on the Tris(ethane-1,2-diamine)cobalt(III) Ion

IJ Clark; RJ Geue; LM Engelhardt; JM Harrowfield; AM Sargeson; AH White

doi:10.1071/ch9931485

Structural Characterization of Encapsulation Reactions Based on the Tris(ethane-1,2-diamine)cobalt(III) Ion

Australian Journal of Chemistry ◽

10.1071/ch9931485 ◽

1993 ◽

Vol 46 (10) ◽

pp. 1485 ◽

Cited By ~ 13

Author(s):

IJ Clark ◽

RJ Geue ◽

LM Engelhardt ◽

JM Harrowfield ◽

AM Sargeson ◽

...

Keyword(s):

Hydrogen Bonding ◽

Metal Ion ◽

Bond Angle ◽

Orthorhombic Space Group ◽

Molecular Rearrangement ◽

Coordination Environment ◽

Catalysed Reaction ◽

Structural And Electronic Properties ◽

Coordination Spheres

On the basis of structural comparisons involving intermediates and side products of encapsulation reactions as well as several cage complexes, the efficiency of the base- catalysed reaction between formaldehyde, nitromethane and [Co(en)3]3+ (en = ethane-1,2-diamine) to give [Co((NO2)2sar)]3+ appears to be explicable in terms of the 'interlocking' of constituent parts without appreciable concomitant bond length or bond angle distortions. Thus, the structures of the podand ligand complexes Λ-[Co(NO2sen)]Cl3.2H2O [orthorhombic, space group P 212121, a 18.755(6), b 11.598(4), c 9.164(3) Ǻ; R 0.038 for No 1735 'observed' reflections] and Δ,Λ-[Co(Nt-Me,NO2sen)]Cl3.4H2O [monoclinic, P21/n, a 18.613(5), b 9.301(3), c 13.779(4) Ǻ, β 107.10(2)°; R 0.051 for No 26441 show very close configurational and conformational similarities to those of the cage complexes Δ,Λ-[Co(NO2azasar)]Cl3.3H2O [monoclinic, P 21/c, a 9.339(3), b 15.479(9), c 17.360(7)Ǻ, β 114.15(3)°; R 0.048 for No 2612], Δ,Λ-[Co((NO2)2sar)]Cl3.2H2O [triclinic, Pī , a 13.592(3), b 10.024(3), c 9.772(3)Ǻ, α 62.89(2),β 82.96(3), γ 85.15(2)°; R 0.045 for No 5646] and Δ,Λ-[Co((OH)2sar)]Cl3.3H2O [monoclinic, P21/c, a 15.97(1), b 8.758(4), c 16.760(4)Ǻ, β 98.72(4)°; R 0.052 for No 2400], as well as to published structures of [Co(en)3]3+, [Co(tame)2]3+ [tame = 1,1,1-tris- ( aminomethyl )ethane = ethylidynetris ( methanamine )] and other cage complexes. Some of these similarities may be associated with common hydrogen-bonding patterns in the solids resulting from anion ' chelation' by adjacent NH moieties in the metal ion coordination spheres. Necessary caution in relating structural and electronic properties is implied by the structure determination for Δ,Λ [Co(Cl,ClCH2absar)](NO3)3 [monoclinic, P 21/c, a 14.750(6), b 9.264(3), c 17.959(7) Ǻ, β 95.80(3)°; R 0.061 for No 1431], one of the products of molecular rearrangement following nitrosation of [Co((NH2)2sar)]3+. Despite marked electronic spectral and electrochemical differences with its parent complex, [Co(Cl,ClCH2absar)](NO3)3 contains cobalt(III) in a coordination environment which remains similar to those in more symmetrical cage complexes.

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Synthesis and Characterization of Bis(4-methylbenzylammonium) Tetrachloridocadmate(II)

International Journal of Inorganic Chemistry ◽

10.1155/2011/274073 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

R. Kefi ◽

M. Zeller ◽

F. Lefebvre ◽

C. Ben Nasr

Keyword(s):

Synthesis And Characterization ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

Hybrid Compound ◽

Coordination Environment ◽

X Ray ◽

Organic Hybrid ◽

Distorted Octahedral ◽

Cp Mas Nmr

The crystal structure of the new inorganic-organic hybrid compound [4-CH3C6H4CH2NH3]2[CdCl4] has been determined by single crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group Pnma with lattice parameters a=10.721(2), b=33.986(6), c=5.326(1) Å, β=97.222(1)°, V=1940.8(7) Å3, and Z=4. The framework of the title compound is built upon layers parallel to (010) made up from corner-sharing CdCl6 octahedra. 4-Methylbenzylammonium cations are situated between the layers and connect them via an N–H⋯Cl hydrogen bonding network. The Cd atom is located on an inversion centre, and the coordination environment is described as distorted octahedral. Solid state 13C CP-MAS NMR spectroscopy is in agreement with the X-ray structure. DFT calculations allow the attribution of the carbon peaks to the independent crystallographic sites. Thermal analysis and infrared spectroscopy were also used to characterize the complex.

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Synthesis and characterization of N-Chloro-o-nitroanilines

Australian Journal of Chemistry ◽

10.1071/ch9760367 ◽

1976 ◽

Vol 29 (2) ◽

pp. 367 ◽

Cited By ~ 6

Author(s):

KJ Chapman ◽

LK Dyall

Keyword(s):

Hydrogen Bonding ◽

Carbon Tetrachloride ◽

Infrared Spectra ◽

Acid Catalysis ◽

Intramolecular Hydrogen Bonding ◽

Synthesis And Characterization ◽

Catalysed Reaction ◽

Lone Pairs ◽

Intramolecular Hydrogen

Chlorine(1) oxide in carbon tetrachloride was found to be an effective reagent for N-chlorinating 2-nitroanilines. These N-chloro-2-nitroanilines are sufficiently stable in solution at 20� to be characterized by reduction and by proton n.m.r, and infrared spectra. The infrared N-H stretching frequencies fall near the low value of 3330 cm-1, apparently because of interaction between N-H bond and chlorine lone pairs; there are also effects of intramolecular hydrogen bonding and of conformation. Under acid catalysis, N-chloro-2-nitroaniline rearranges to C-chlorinated 2-nitroanilines, while with alkali it cyclizes to benzofuroxan. The acid-catalysed reaction has the same features as the Orton rearrangement of N-chloroacetanilides.

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Lewis-Base Adducts of Group 11 Metal(I) Compounds. LVII. Crystal-Structure of Bis(2,6-diacetyl-pyridine)silver(I) Perchlorate

Australian Journal of Chemistry ◽

10.1071/ch9891381 ◽

1989 ◽

Vol 42 (8) ◽

pp. 1381 ◽

Cited By ~ 4

Author(s):

SB Silong ◽

LM Engelhardt ◽

AH White

Keyword(s):

Crystal Structure ◽

Structural Characterization ◽

Room Temperature ◽

Bond Angle ◽

Lewis Base ◽

The Other ◽

Tridentate Ligands ◽

Coordination Spheres ◽

Silver Atoms

The synthesis and room temperature structural characterization of the title compound [AgL2]+(C104)-, L= 2,6-diacetylpyridine, are reported. Crystals are orthorhombic, Pcan, a 19.629(7), b 14.603(4) and c 14.469(4) � , Z = 8; R was 0.050 for 1987 'observed' reflections. The structure contains two independent [AgL2]+ species, the central nitrogen atoms of the quasi-tridentate ligands being opposed in the coordination spheres of the silver atoms. Both have crystallographically imposed 2 symmetry; in one, this is normal to the N-Ag-N line [actual bond angle, 175.6(2); Ag-N, 2.316(6), Ag-O, 2.589(7) and 2.522(7) � ], relating the two ligands. In the other, it is coincident; for one ligand Ag-N and Ag-O are 2.285(8) and 2.500(8) � , while for the other the two values are 2.271(8) and 2.543(7) �. The silver-nitrogen distances are appreciably longer than the value of 2.166(4) � found for the [Ag( py )2]+ cation.

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The dinuclear scandium(III) cyclooctatetraenyl chloride complex di-μ-chlorido-bis[(η8-cyclooctatetraene)(tetrahydrofuran-κO)scandium(III)]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229617005678 ◽

2017 ◽

Vol 73 (5) ◽

pp. 420-423 ◽

Cited By ~ 2

Author(s):

Zheng Zhou ◽

Joshua Greenough ◽

Zheng Wei ◽

Marina A. Petrukhina

Keyword(s):

Molecular Structure ◽

Single Crystal ◽

Bond Length ◽

Metal Ion ◽

Chloride Complex ◽

X Ray Diffraction ◽

Coordination Environment ◽

X Ray ◽

Bond Lengths

Only a few cyclooctatetraene dianion (COT) π-complexes of lanthanides have been crystallographically characterized. This first single-crystal X-ray diffraction characterization of a scandium(III) COT chloride complex, namely di-μ-chlorido-bis[(η8-cyclooctatetraene)(tetrahydrofuran-κO)scandium(III)], [Sc2(C8H8)2Cl2(C4H8O)2] or [Sc(COT)Cl(THF)]2 (THF is tetrahydrofuran), (1), reveals a dimeric molecular structure with symmetric chloride bridges [average Sc—Cl = 2.5972 (7) Å] and a η8-bound COT ligand. The COT ring is planar, with an average C—C bond length of 1.399 (3) Å. The Sc—C bond lengths range from 2.417 (2) to 2.438 (2) Å [average 2.427 (2) Å]. Direct comparison of (1) with the known lanthanide (Ln) analogues (La, Ce, Pr, Nd, and Sm) illustrates the effect of metal-ion (M) size on molecular structure. Overall, the M—Cl, M—O, and M—C bond lengths in (1) are the shortest in the series. In addition, only one THF molecule completes the coordination environment of the small ScIII ion, in contrast to the previously reported dinuclear Ln–COT–Cl complexes, which all have two bound THF molecules per metal atom.

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Structural and Electronic Properties of Iron(II) Complexes of 2-(1,2,4-Triazol-3-yl)pyridine and Substituted Derivatives

Australian Journal of Chemistry ◽

10.1071/ch9950035 ◽

1995 ◽

Vol 48 (1) ◽

pp. 35 ◽

Cited By ~ 17

Author(s):

KH Sugiyarto ◽

DC Craig ◽

AD Rae ◽

HA Goodwin

Keyword(s):

Metal Ion ◽

Complex Cation ◽

Iron Complex ◽

High Symmetry ◽

Orthorhombic Space Group ◽

Metastable Form ◽

Structural And Electronic Properties ◽

Region Temperature ◽

A Minor

Iron(II) and nickel(II) tris(ligand) complexes of 2-(triazol-3-yl)pyridine and the substituted derivatives 2-(1(N)-methyltriazol-3-yl)pyridine and -(1,5-dimethyltriazol-3-yl)pyridine have been prepared. Coordination of the dimethyl -substituted ligand via N(4) of the triazolyl moieties is confirmed by structure determination of [FeL3] [BF4]2, which has the mer configuration. Tris (2-(1,5-dimethyltriazol-3-yl)pyridine)iron(II) bis ( tetrafluoroborate ): orthorhombic, space group Pbca, a 11.568(3), b 19.442(4), c 30.551(8) Ǻ, Z 8. The methyl substituents appear to have only a minor influence on the donor properties of the ligands, all three of which have field strengths in the iron(II) quintet ↔ singlet crossover region. Temperature-induced singlet ↔ quintet transitions occur in salts of the [FeN6]2+ derivatives in both the solid and solution states. Mossbauer effect studies reveal the complexity of the solid state properties of salts of the iron complex of 2-(1(N)-methyltriazol-3-yl)pyridine and suggest that there is a fundamental change with time in the geometry of the complex cation. The metastable form of the complex hexafluorophosphate salt shows virtually no quadrupole splitting in the spectrum for the quintet state species, which implies high symmetry for the metal ion environment. Mossbauer studies further reveal the presence of multiple iron(II) sites in the lattice for salts containing either the N-methyl or the unsubstituted ligand.

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Characterization of a monolayer graphitic structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171535 ◽

1994 ◽

Vol 52 ◽

pp. 760-761

Author(s):

X. Lin ◽

X. K. Wang ◽

V. P. Dravid ◽

J. B. Ketterson ◽

R. P. H. Chang

Keyword(s):

Three Dimensional ◽

Single Layer ◽

Synthesis Process ◽

Graphitic Structure ◽

Positive Gaussian Curvature ◽

Graphitic Sheet ◽

Structural And Electronic Properties ◽

New Material ◽

Hexagonal Network

For small curvatures of a graphitic sheet, carbon atoms can maintain their preferred sp2 bonding while allowing the sheet to have various three-dimensional geometries, which may have exotic structural and electronic properties. In addition the fivefold rings will lead to a positive Gaussian curvature in the hexagonal network, and the sevenfold rings cause a negative one. By combining these sevenfold and fivefold rings with sixfold rings, it is possible to construct complicated carbon sp2 networks. Because it is much easier to introduce pentagons and heptagons into the single-layer hexagonal network than into the multilayer network, the complicated morphologies would be more common in the single-layer graphite structures. In this contribution, we report the observation and characterization of a new material of monolayer graphitic structure by electron diffraction, HREM, EELS.The synthesis process used in this study is reported early. We utilized a composite anode of graphite and copper for arc evaporation in helium.

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