ChemInform Abstract: X-RAY CRYSTAL STRUCTURE OF THE 1-2 ADDUCT OF ALUMINUM TRICHLORIDE WITH ACETONITRILE, AN INTERESTING EXAMPLE OF AUTO-COMPLEX FORMATION

Di-D-fructose 2′, 1:2,1′-dianhydrides form complexes with metal cations if the two anomeric carbon atoms have the same configuration. Such anomers have the central 1,4-dioxane ring in a flexible form; complex formation involves O-1, O-1′, O-3, and O-3′, as confirmed by the X-ray crystal structure of the strontium complex of the β,β-dipyranose anomer. The α,β-anomers, and dianhydrides containing only furanose rings, do not form such complexes. Keywords: difructose dianhydrides, complex formation with cations, crystal structure of complex, chromatographic separation on ion-exchange resins.

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Sterically promoted N2 bound tetrazolate complex formation in the 1,3-dipolar cycloaddition of p-OMeC6H4CN to the coordinated azide in the palladium complex [Pd(N-N-S)(N3)]. X-ray crystal structure of [Pd(N-N-S)(N4C-p-OMeC6H4]

Inorganica Chimica Acta ◽

10.1016/s0020-1693(00)85447-x ◽

1991 ◽

Vol 185 (2) ◽

pp. 221-227 ◽

Cited By ~ 12

Author(s):

Ramprasad Das ◽

Parimal Paul ◽

Kamalaksha Nag ◽

K. Venkatsubramanian

Keyword(s):

Crystal Structure ◽

Complex Formation ◽

Palladium Complex ◽

Dipolar Cycloaddition ◽

X Ray

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3,5-Bis(2-hydroxyphenyl)-1H-1,2,4-triazole based ligands — protonation and metal complex formation

Chemical Papers ◽

10.2478/s11696-008-0043-x ◽

2008 ◽

Vol 62 (4) ◽

Cited By ~ 4

Author(s):

Stefan Stucky ◽

Nadine Koch ◽

Uwe Heinz ◽

Kaspar Hegetschweiler

Keyword(s):

Crystal Structure ◽

Cyclic Voltammetry ◽

Nitrogen Atom ◽

Complex Formation ◽

1H Nmr ◽

Temperature Dependent ◽

Spectroscopic Measurements ◽

X Ray ◽

Vis Spectroscopy ◽

Spectrophotometric Titrations

Abstract3,5-Bis(2-hydroxyphenyl)-1H-1,2,4-triazole (H2La) and 4-[3,5-bis(2-hydroxyphenyl)-1H-1,2,4-triazol-1-yl]benzoic acid (H3Lb) have been prepared, and crystal structure of the intermediate 2-(2-hydroxyphenyl)-4H-1,3-benzoxazin-4-one has been determined. Temperature dependent 1H NMR spectroscopic measurements of H2La indicated dynamic behavior with the equilibrium between the two asymmetric tautomers. For H3Lb, pD-dependent 1H NMR spectroscopic measurements showed small but characteristic shifts in the range of 0 ≤ pD ≤ 1, indicative of a triazole nitrogen atom protonation; the corresponding pK a of 0.98 ± 0.04 was determined by spectrophotometric titrations. (H2O, 26°C, 1 M KCl/HCl). Formation of [FeIII(La)]+ (pH 2.5) and [FeIII(La)2]− (pH > 6) was verified by UV-Vis spectroscopy. Complex formation of H3Lb with Al3+ and VO2+ was investigated by 1H NMR spectroscopic titration and cyclic voltammetry, respectively. Single crystals of the phenoxo bridged [VVO(HLb)(EtO)]2·2EtOH were characterized by X-ray structural analysis.

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X-Ray crystal structure of the 1 : 2 adduct of aluminium trichloride with acetonitrile; an interesting example of auto-complex formation

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39760000477 ◽

1976 ◽

pp. 477 ◽

Cited By ~ 12

Author(s):

Judith A. K. Howard ◽

Lesley E. Smart ◽

Christopher J. Gilmore

Keyword(s):

Crystal Structure ◽

Complex Formation ◽

X Ray ◽

Aluminium Trichloride

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A study on α-RuCl3 crystal structure by scanning tunneling microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152124 ◽

1989 ◽

Vol 47 ◽

pp. 30-31

Author(s):

H.-J. Cantow ◽

H. Hillebrecht ◽

S. Magonov ◽

H. W. Rotter ◽

G. Thiele

Keyword(s):

Crystal Structure ◽

Density Distribution ◽

Scanning Tunneling Microscopy ◽

Electron Density ◽

Structure Determination ◽

Electron Density Distribution ◽

Scanning Tunneling ◽

Monoclinic Space Group ◽

Tunneling Microscopy ◽

X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

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