Isomerisierungsreaktionen von cis- und trans-Dicarben-Komplexen des Typs M(CO)4L2 (M = Cr, Mo, W).

A series of bis-carbene complexes cis-M(CO)4L2 (M = Cr, Mo, W) containing cyclic carbene ligands (L= 1,2-dimethyl-4-pyrazoline-3-ylidene, 1,3-dimethyl-4-imidazoline-2-ylidene, 2,4-dimethyl-1,2,4-triazoline-3-ylidene and 1,3-dimethyl-benzimidazoline-2-ylidene) was prepared, and the photo-induced conversion to the corresponding trans-isomers was investigated. The trane-M(CO)4L2 complexes were characterized by their IR and 1H NMR spectra, and their irreversible thermal isomerisation to the thermodynamically more stable cis-isomers was studied both in solution and in the solid state.

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Zum ambidenten Charakter des Cyanotrihydroborat-Liganden in Uran(IV)-Organylen / On the Ambident Nature of the Cyanotrihydroborate Ligand in Organouranium(IV) Complexes

Zeitschrift für Naturforschung B ◽

10.1515/znb-1983-1109 ◽

1983 ◽

Vol 38 (11) ◽

pp. 1369-1374 ◽

Cited By ~ 8

Author(s):

R. Dieter Fischer ◽

Kenan Yünlü

Keyword(s):

Solid State ◽

Nmr Spectra ◽

Colour Change ◽

Metal Coordination ◽

Temperature Dependent ◽

H Nmr ◽

Trigonal Bipyramidal ◽

Oligomeric Complex

Both the acceptedly oligomeric complex [(C5H5)3U(μ-NCBH3)]n (1) and its hitherto unknown, appreciably more soluble and volatile homologue, [(CH3C5H4)3U(μ-NCBH3)]n (2), display NIR/VIS spectra typical of trigonal bipyramidal (tbp) metal coordination in the solid state, but of pseudotetrahedral (ψ-Td) coordination e.g. in CH2CI2 and C6H5CH3 solution. The 1H NMR spectra of 2 in these non coordinating solvents can be best explained in terms of temperature dependent equilibria involving the two rapidly interconverting ψ-Td-isomers (CH3C5H4)3U(η3-H3BCN) and (CH3C5H4)3UNCBH3. A reversible colour change: green ⇋ brown at 130-150 °C also suggests the facile rupture of U-H and U-N bonds, respectively, in thermally excited, polycrystalline (2).

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1 H NMR spectra dataset and solid-state NMR data of cowpea ( Vigna unguiculata )

Data in Brief ◽

10.1016/j.dib.2017.01.013 ◽

2017 ◽

Vol 11 ◽

pp. 136-146 ◽

Cited By ~ 5

Author(s):

Elenilson G. Alves Filho ◽

Lorena M.A. Silva ◽

Elizita M. Teofilo ◽

Flemming H. Larsen ◽

Edy S. de Brito

Keyword(s):

Solid State ◽

Vigna Unguiculata ◽

Solid State Nmr ◽

Nmr Spectra ◽

H Nmr ◽

Nmr Data

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New homoleptic gold carbene complexes via Ag–Au transmetalation: synthesis and application of [Au(diNHC)2]3+ cations as 1H-NMR and UV-vis halide sensors

New Journal of Chemistry ◽

10.1039/c9nj05809e ◽

2020 ◽

Vol 44 (14) ◽

pp. 5343-5353

Author(s):

Marco Baron ◽

Anna Dall’Anese ◽

Alessandro Miolato ◽

Maddalena L. C. Cairoli ◽

Valerio Di Marco ◽

...

Keyword(s):

1H Nmr ◽

Carbene Ligands ◽

Carbene Complexes ◽

H Nmr ◽

Anion Sensors

Novel homoleptic gold(iii) complexes with bidentate N-heterocyclic carbene ligands have been successfully synthesised by transmetalation reaction and studied as anion sensors in solution by means of 1H NMR and UV-vis titration experiments.

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Phenylsilane dehydrocoupling and addition to styrene catalyzed by (R-indenyl)Ni(phosphine)(methyl) complexes

Canadian Journal of Chemistry ◽

10.1139/v08-132 ◽

2009 ◽

Vol 87 (1) ◽

pp. 280-287 ◽

Cited By ~ 14

Author(s):

Yaofeng Chen ◽

Davit Zargarian

Keyword(s):

Solid State ◽

Nmr Spectra ◽

Variable Temperature ◽

Structural Parameters ◽

Catalytic Cycle ◽

Synthesis And Characterization ◽

H Nmr ◽

Solid State Structures ◽

Indenyl Complexes

This report describes the synthesis and characterization of the Ni–Me complexes (R-indenyl)Ni(PR′3)Me (R = 1-i-Pr, 1-SiMe3, and 1,3-(SiMe3)2; R′= Me, Ph) and outlines their catalytic reactivities in the dehydrogenative oligomerization of PhSiH3 and its addition to styrene in the absence of initiators/activators. Observation of higher hydrosilylation activities for PPh3-based compounds featuring bulky substituents on the indenyl ligand confirms earlier suggestions that phosphine dissociation is an important component of the catalytic cycle for this reaction. In contrast, oligomerization of PhSiH3 is more facile with PMe3-based precursors and independent of the steric bulk of the indenyl ligand, implying that this reaction does not involve phosphine dissociation. These conclusions are consistent with the variable-temperature 1H NMR spectra of {1,3,-(SiMe3)2-indenyl}Ni(PR′3)Me and various structural parameters observed in the solid-state structures of {1,3,-(SiMe3)2-indenyl}Ni(PPh3)Me, {1,3,-(SiMe3)2-indenyl}Ni(PMe3)Cl, and {1-SiMe3-indenyl}Ni(PMe3)Me.Key words: nickel-indenyl complexes, hydrosilylation, hydrosilane oligomerization.

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Notizen: High-field (500 MHz) 1H NMR Spectra of Retinoic Acids and Arotinoids by Two-dimensional Chemical Shift Correlation (2D) Spectroscopy

Zeitschrift für Naturforschung B ◽

10.1515/znb-1988-0829 ◽

1988 ◽

Vol 43 (8) ◽

pp. 1072-1074 ◽

Cited By ~ 3

Author(s):

Bruno Perly ◽

Giuseppe C. Pappalardo ◽

Michael Klaus ◽

Enzo Montoneri

Keyword(s):

Chemical Shift ◽

Nmr Spectra ◽

Chair Conformation ◽

Two Dimensional ◽

Trans Isomers ◽

Chemical Shift Correlation ◽

H Nmr ◽

Retinoic Acids ◽

Cis And Trans Isomers ◽

Cis And Trans

AbstractThe 1H NMR spectra (in DMSO solution at 300 K) of retinoic acids (cis- and trans-isomers) and new arotinoids were run at 500 MHz and assigned by using homo- and heteronuclear two-dimensional (2D) chemical shift correlation experiments. Spectral analysis was indicating, on the basis of 7 values, that the ring C(l)-C(2)-C(3)-C(4)-C(5)-C(6) adopts, in all compounds, a chair conformation.

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Triphenylphosphine complexes of cadmium(II) perchlorate, nitrate, and trifluoroacetate preparation, characterization, and spectral studies

Canadian Journal of Chemistry ◽

10.1139/v81-482 ◽

1981 ◽

Vol 59 (23) ◽

pp. 3267-3272 ◽

Cited By ~ 5

Author(s):

Ram G. Goel ◽

Narendra K. Jha

Keyword(s):

Solid State ◽

Elemental Analysis ◽

Vibrational Spectra ◽

Nmr Spectra ◽

Ionic Species ◽

Spectral Studies ◽

Spectral Measurements ◽

Coordinate Structure ◽

H Nmr ◽

Metal Ligand

1:2 complexes, CdX2(PPh3)2, where X = ClO4, NO3, CF3CO2 and 1:1 complex, Cd(CF3CO2)2PPh3, have been isolated and characterized by elemental analysis and by vibrational and 31P—{lH} nmr spectral measurements. Conductance measurements show that the complexes behave as non-ionic species in dichloromethane. The vibrational spectra of the perchlorato complex are consistent with a six-coordinate structure in the solid state as well as in solution but it is difficult to deduce the structures of the nitrato and trifluoroacetato complexes from the spectral data. Assignments for the metal–ligand stretching frequencies for all the four complexes have been proposed. The 3lP—{1H} nmr spectra of the four complexes have been discussed. Formation of the 1:3 and 1:4 complexes, Cd(ClO4)2(PPh3)3 and Cd(ClO4)2(PPh3)4, in solution, has also been established by 31P—{lH} nmr spectral measurements.

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Metallkomplexe der Phosphinsäuren, XVI [1]. cis-trans-Isomerie bei planaren Palladiumund Platinkomplexen [RR′ PS2]2M [2] / Metal Complexes of Phosphinic Acids, XVI [1]. cis-trans Isomers of Planar Palladium and Platinum Complexes [RR'PS2]2M [2]

Zeitschrift für Naturforschung B ◽

10.1515/znb-1980-0222 ◽

1980 ◽

Vol 35 (2) ◽

pp. 239-241 ◽

Cited By ~ 3

Author(s):

Wilhelm Kuchen ◽

Reinhard Uppenkamp

Keyword(s):

Metal Complexes ◽

Nmr Spectra ◽

Platinum Complexes ◽

Trans Isomers ◽

H Nmr ◽

Cis And Trans Isomers ◽

Phosphinic Acids ◽

Palladium And Platinum Complexes ◽

Dithiophosphinic Acids ◽

Cis And Trans

Unsymmetrically substituted dithiophosphinic acids RR'P(S)SH give planar metal chelates [RR'PS2]2M 1 [M = Pd(II), Pt(II)]. It can be shown by comparison of their 31P-{1H} NMR spectra with those of symmetrically substituted compounds [R2PS2]2M that in the synthesis of 1 equimolar mixtures of the cis and trans isomers are formed.

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Cis- und trans-Isomere des 1.5-Dimethyl-3.6-diphenoxy-3.6-dithioxo-1.2.4.5-tetraza-3.6-diphosphacyclohexans (des 1.5-Dimethyl-3.6-diphenoxy-3.6-dithioxocyclodi(phosphadiazans)) / Cis- and trans-Isomers of 1,5-Dimethyl-3,6-diphenoxy-3,6-dithioxo-1,2,4,5-tetraza-3,6-diphosphacyclohexane (of 1,5-Dimethyl-3,6-diphenoxy-3,6-dithioxocyclodi(phosphadiazane))

Zeitschrift für Naturforschung B ◽

10.1515/znb-1977-1214 ◽

1977 ◽

Vol 32 (12) ◽

pp. 1435-1438 ◽

Cited By ~ 5

Author(s):

Udo Engelhardt ◽

Hans-Joachim Merrem

Keyword(s):

Title Compound ◽

Nmr Spectra ◽

Trans Isomers ◽

H Nmr ◽

Cis And Trans Isomers ◽

Cis And Trans

C6H5O-(S)P(N(CH3)-NH2)2 reacts with C6H5O(S)PCl2 to give the title compound. The cis- and trans-isomers of this product have been separated and are characterized by their IR, 1H NMR and 31P NMR spectra.

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Spectroscopic studies of some Pd(II), Pt(II), Ag(I), and Au(III) complexes of 4,6-diamino-2-thiopyrimidine and 4,6-diamino-2-methylthiopyrimidine. Structure and binding site determination

Canadian Journal of Chemistry ◽

10.1139/v88-042 ◽

1988 ◽

Vol 66 (2) ◽

pp. 249-255 ◽

Cited By ~ 20

Author(s):

M. D. Gutiérrez ◽

R. López ◽

M. A. Romero ◽

J. M. Salas

Keyword(s):

Magnetic Susceptibility ◽

Solid State ◽

Nmr Spectra ◽

Spectroscopic Studies ◽

Spectroscopic Techniques ◽

Conductivity Measurements ◽

Sulphur Atom ◽

H Nmr ◽

Ring Nitrogen ◽

Ring Nitrogen Atom

Interaction of Pd(II), Pt(II), Ag(I), and Au(III) with 4,6-diamino-2-thiopyrimidine (DATP) and 4,6-diamino-2-methyl-thiopyrimidine (DAMTP) in aqueous medium resulted in the formation of new complexes which have been characterized by elemental analysis, ir, 1H-nmr spectroscopic techniques, magnetic susceptibility measurements in the solid state, and conductivity measurements in DMF solution. The ir and 1H-nmr spectra were consistent with coordination involving the non-protonated ring nitrogen atom, the exocyclic sulphur atom, or N,S-chelation.

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