Complexes of dithiobenzoic acids. III.1H and 13C nuclear magnetic reonance studies of a series of tetrakis(dithiobenzoato)molybdenum(IV) complexes

1980 ◽  
Vol 58 (22) ◽  
pp. 2314-2317 ◽  
Author(s):  
T. Roberie ◽  
N. S. Bhacca ◽  
D. Lankin ◽  
J. Selbin
Keyword(s):  
Charge Density ◽  
Electron Density ◽  
Tetraalkylammonium Salts ◽  
Nmr Data ◽  
C Nmr ◽  
Nuclear Magnetic

A series of dithiocarboxalato (X-dtb) complexes of molybdenum(IV), Mo(X-dtb)4, where the para substituent X = H, CH3, CH3O, F, C6H5, CHO, C6H5CO, or (n-C4H9)2N, the parent acids and tetraalkylammonium salts were studied by 1H and 13C nmr in order to monitor the expected charge density shifts as a function of the group X. Analysis of the 13C nmr data unexpectedly revealed an absence of delocalization of electron density either from molybdenum to ligand or from ligand to molybdenum.

15N and 13C nuclear magnetic resonance of deoxydinucleotide monophosphates. II. Protonation of the homo dimers deoxycytidylyl-(3′,5′)-deoxycytidine, thymidylyl-(3′,5′)-thymidine, and deoxyadenylyl-(3′,5′)-deoxyadenosine in dimethyl sulfoxide

1990 ◽  
Vol 68 (11) ◽  
pp. 2033-2038 ◽  
Author(s):  
Giovanna Barbarella ◽  
Massimo Luigi Capobianco ◽  
Luisa Tondelli ◽  
Vitaliano Tugnoli
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Dimethyl Sulfoxide ◽  
Phosphate Group ◽  
Nmr Data ◽  
13C Nuclear Magnetic Resonance ◽  
C Nmr ◽  
Nuclear Magnetic

The preferential protonation sites of the homo dimers deoxycytidylyl-(3′,5′)-deoxycytidine, thymidylyl-(3′,5′)-thymidine, and deoxyadenylyl-(3′,5′)-deoxyadenosine were established by nitrogen-15 and carbon-13 NMR in dimethyl sulfoxide, in the presence of varying amounts of CF3COOH. The nitrogen-15 NMR data show that in d(CpC) the capability of the two N3 nitrogens to accept the proton is slightly different. In d(TpT) and d(ApA) the protonation of the phosphate group leads to significant variations of the chemical shift of the carbons adjacent to phosphorus. Keywords: deoxydinucleotides, protonation, 15N and 13C NMR.

Hypercoordinate β-carbon in Grubbs and Schrock olefin metathesis metallacycles

2015 ◽  
Vol 44 (40) ◽  
pp. 17660-17672 ◽  
Author(s):  
Premaja R. Remya ◽  
Cherumuttathu H. Suresh
Keyword(s):  
Electron Density ◽  
Olefin Metathesis ◽  
Bond Order ◽  
Structural Bond ◽  
Nmr Data ◽  
C Nmr

From the analysis of structural, bond order, electron density and 13C NMR data of a large variety of ruthenacyclobutanes and tungstenacyclobutanes, we show that the Cβ of the metallacycle is pentacoordinate.

29Si-, 31P- und 13C-Kernresonanzuntersuchungen an N-silylierten Triorganophosphiniminen / Silicon-29, Phosphorus-31, and Carbon-13 Nuclear Magnetic Resonance Investigations of N-Silylated Triorganophosphine Imines

1977 ◽  
Vol 32 (9) ◽  
pp. 967-974 ◽  
Author(s):  
Wolfgang Buchner ◽  
Werner Wolfsberger
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shifts ◽  
Spin Splitting ◽  
Bonding Mechanism ◽  
Nmr Data ◽  
Qualitative Interpretation ◽  
Chloro Derivatives ◽  
C Nmr ◽  
Nuclear Magnetic

29Si, 31P and, in part, 13C NMR data are reported for N-trimethylsilyl-triorganophosphine imines as well as some siliconsubstituted methoxy and chloro derivatives. The spin-spin splitting pattern of the 29Si{1H} spectra is discussed for disilanes of the type (RR′R″P=N-SiMe2-)2. A qualitative interpretation of 29Si chemical shifts is preferably being based on hyperconjugation rather than a (p-d)n bonding mechanism. The preparation of a series of bis(phosphinimino)silanes and 1,2-bis(phosphinimino)disilanes is described.

Glucan isolated from leaves of Althaea officinalis L.

1983 ◽  
Vol 48 (7) ◽  
pp. 2082-2087 ◽  
Author(s):  
Alžbeta Kardošová ◽  
Jozef Rosík ◽  
Rudolf Toman ◽  
Peter Capek
Keyword(s):  
Medicinal Plant ◽  
Periodate Oxidation ◽  
Linear Structure ◽  
Water Soluble ◽  
Partial Hydrolysis ◽  
Methylation Analysis ◽  
Glycosidic Bonds ◽  
Nmr Data ◽  
Althaea Officinalis ◽  
C Nmr

A water-soluble low-molecular D-glucan was isolated from leaves of the medicinal plant marsh-mallow (Althaea officinalis L.). The results of methylation analysis, partial hydrolysis, periodate oxidation, and 13C NMR data indicated a virtually linear structure with α-(1→6) glycosidic bonds.

Synthesis and characteristics of ethylenediamine-N,N'-di-S-α-isovalerate and isomers of its cobalt(III) complexes

1982 ◽  
Vol 47 (1) ◽  
pp. 210-216 ◽  
Author(s):  
Milan Strašák ◽  
František Bachratý ◽  
Jaroslav Majer
Keyword(s):  
Amino Acids ◽  
Absolute Configuration ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Chemical Parameters ◽  
Methyl Group ◽  
Nmr Data ◽  
Physico Chemical ◽  
Natural Amino Acids ◽  
C Nmr

The synthesis and physico-chemical parameters are described of a new complexone based on natural amino acids, viz. ethylenediamine-N,N'-di-S-α-isovalerate (SS-EDDIV). 1H- and 13C-NMR data revealed that the methyl group in the substance are not equivalent. The isomers of the cobalt(III) complex with the asymmetric tetradentate SS-EDDIV ligand were prepared and separated; their characteristics are given. The absolute configuration of two of the five theoretically feasible isomers was determined based on their electronic absorption spectra and circular dichroism data.

scholarly journals Structural Investigations of C-Nitrosobenzenes. Part 3.1 Solid-state and Solution 13C NMR Studies, and Crystal Structure of E-(4-CIC6H4NO)2

1999 ◽  
Vol 23 (3) ◽  
pp. 202-203
Author(s):  
Daniel A. Fletcher ◽  
Brian G. Gowenlock ◽  
Keith G. Orrell ◽  
David C. Apperley ◽  
Michael B. Hursthouse ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
13C Nmr ◽  
Nmr Studies ◽  
Structural Investigations ◽  
Nmr Data ◽  
C Nmr

Solid-state and solution 13C NMR data for the monomers and dimers of 3- and 4-substituted nitrosobenzenes, and the crystal structure of E-(4-CIC6H4NO)2 are reported.

Revisiting the charge density analysis of 2,5-dichloro-1,4-benzoquinone at 20 K

2017 ◽  
Vol 73 (4) ◽  
pp. 654-659 ◽  
Author(s):  
Zhijie Chua ◽  
Bartosz Zarychta ◽  
Christopher G. Gianopoulos ◽  
Vladimir V. Zhurov ◽  
A. Alan Pinkerton
Keyword(s):  
Charge Density ◽  
Electron Density ◽  
Topological Analysis ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
Total Electron Density ◽  
Total Electron ◽  
Structure Factors ◽  
Density Analysis ◽  
Experimental Charge Density

A high-resolution X-ray diffraction measurement of 2,5-dichloro-1,4-benzoquinone (DCBQ) at 20 K was carried out. The experimental charge density was modeled using the Hansen–Coppens multipolar expansion and the topology of the electron density was analyzed in terms of the quantum theory of atoms in molecules (QTAIM). Two different multipole models, predominantly differentiated by the treatment of the chlorine atom, were obtained. The experimental results have been compared to theoretical results in the form of a multipolar refinement against theoretical structure factors and through direct topological analysis of the electron density obtained from the optimized periodic wavefunction. The similarity of the properties of the total electron density in all cases demonstrates the robustness of the Hansen–Coppens formalism. All intra- and intermolecular interactions have been characterized.

Angular terms in the electron density for the phosphine molecule

1956 ◽  
Vol 52 (4) ◽  
pp. 703-711 ◽  
Author(s):  
R. A. Ballinger ◽  
N. H. March
Keyword(s):  
Variational Method ◽  
Charge Density ◽  
Electron Density ◽  
Legendre Polynomials ◽  
Molecular Axis ◽  
Thomas Fermi ◽  
Line Charge ◽  
Density Map ◽  
Circular Line

ABSTRACTAn attempt is made to calculate the first few angular terms in an expansion of the electron density for the phosphine molecule in Legendre polynomials. Such an expansion is appropriate for a model in which the three hydrogen nuclei are smeared to form a circular line charge. The Thomas–Fermi approximation has been used in conjunction with the variational method. The variational density employed includes p and f angular terms. An approximate charge density map is constructed for a plane containing the molecular axis in order to demonstrate the effect of the angular terms.

1-Carba-arachno-pentaborane(10) Derivatives

1997 ◽  
Vol 62 (8) ◽  
pp. 1254-1262 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Hans-Jörg Schanz
Keyword(s):  
High Yield ◽  
Exchange Reactions ◽  
Nmr Data ◽  
Substituted 1 ◽  
C Nmr

The formation of organo substituted 1-carba-arachno-pentaborane(10) derivatives is shown to proceed in high yield via in situ generated 1,1,1-tris(diethylboryl)propane (2) from diethyl(propyn-1-yl)borane (1) by hydroboration with an excess of diethylborane (hydride bath). In the hydride bath, exchange reactions between 2 and other geminal bis(diethylboryl)alkanes take place until the carbaborane skeleton is formed. If tris(diethylboryl)methane is used under the same conditions, the corresponding 1-carba-arachno-pentaborane(10) derivatives 11 and 12 are formed in mixture with other unknown boranes or carboranes. 11B and 13C NMR data are presented to allow for straightforward identification of the 1-carba-arachno-pentaboranes(10).

scholarly journals Assignment of 1 H- and 13 C-NMR data for four helminthosporol analogs with the bicyclo[3.2.1]oct-6-ene framework

2018 ◽  
Vol 56 (11) ◽  
pp. 1130-1134
Author(s):  
Kenji Tomita ◽  
Sho Miyazaki ◽  
Kazuo Furihata ◽  
Masatoshi Nakajima ◽  
Tadao Asami
Keyword(s):  
Nmr Data ◽  
C Nmr
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