1H NMR Study of 3,5-Disubstituted 6-Oxo-1,6-dihydro-1,2,4-triazines

1995 ◽  
Vol 60 (2) ◽  
pp. 251-256
Author(s):  
Karel Nálepa ◽  
Aleš Halama ◽  
Taťjana Nevěčná ◽  
Vojtěch Bekárek
Keyword(s):  
Temperature Dependence ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Thermodynamic Characteristics ◽  
H Nmr ◽  
Nmr Study

1H NMR spectra have been measured of seven 3,5-disubstituted 6-oxo-1,6-dihydro-1,2,4-triazines, and tautomerism of these compounds has been evaluated in connection with the nature of substituents, medium, and temperature. The title compounds exist in their benzyl or benzylidene forms or as a mixture of both forms. Thermodynamic characteristics of the transition between the two forms have been determined from the temperature dependence of NMR spectra of three derivatives.

A 15N, 13C, and 1H NMR study of reaction products from arylguanidines and chloroformate esters

1991 ◽  
Vol 56 (7) ◽  
pp. 1505-1511 ◽  
Author(s):  
Antonín Lyčka ◽  
Karel Palát
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
Reaction Products ◽  
H Nmr ◽  
Nmr Study

The 15N, 13C, and 1H NMR spectra of the reaction products from arylguanidines with two mols of chloroformate esters have been measured. With application of the corresponding 15N isotopomer it has been proved that the reaction products have the structures IIIa-IIIc.

Wideline 1H NMR Study on Hydrated Layered Sulfides K0.5(H2O)y[NbS2] and Na0.5(H2O)y[NbS2]

1977 ◽  
Vol 32 (9) ◽  
pp. 1033-1037 ◽  
Author(s):  
Anton Lerf ◽  
Paul Burkert ◽  
Jürgen O. Besenhard ◽  
Robert Schöllhorn
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
Room Temperature ◽  
Interlayer Space ◽  
Water Molecules ◽  
Structural Scheme ◽  
H Nmr ◽  
Nmr Study

H NMR spectra of different hydration stages show that the water molecules in hydrated layered niobium sulfides A0.5(H2O)y[NbS2] are rather mobile at room temperature. A structural scheme of water arrangement in the interlayer space is proposed with the C2-axis of the H2O molecules parallel to the basal planes of the NbS2 layer units.

Preparation and 1H NMR study of soluble alkoxy, alkyl and arylamido derivatives of sodium tetraamidoaluminate

1982 ◽  
Vol 47 (2) ◽  
pp. 384-391 ◽  
Author(s):  
Otomar Kříž ◽  
František Mareš ◽  
Bohuslav Čásenský
Keyword(s):  
1H Nmr ◽  
Aromatic Amines ◽  
Nmr Spectra ◽  
Pyridine Solution ◽  
Molecular Weights ◽  
H Nmr ◽  
Nmr Study ◽  
Derivatives Of

Sodium tetraamidoaluminate reacts with alcohols and aromatic amines under formation of sodium alkoxyimidoaluminates or amido(arylamido)aluminates, respectively. The corresponding sodium amido(alkylamido)aluminates were prepared from sodium tetraamidoaluminate and sodium tetrakis(alkylamido)aluminates in 1,2-dimethoxyethane or pyridine solution. 1H NMR spectra and in some cases also the cryoscopic molecular weights of the prepared compounds were measured.

119Sn, 15N, 13C, and 1H NMR Study of the Intramolecular Sn-N Donor-Acceptor Interaction in [2-(Dimethylaminomethyl)phenyl]stannanes

1998 ◽  
Vol 63 (7) ◽  
pp. 977-989 ◽  
Author(s):  
Aleš Růžička ◽  
Vladimír Pejchal ◽  
Jaroslav Holeček ◽  
Antonín Lyčka ◽  
Klaus Jacob
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
Intramolecular Interaction ◽  
Coupling Constants ◽  
Acceptor Interaction ◽  
H Nmr ◽  
Nmr Parameters ◽  
Nmr Study ◽  
Donor Acceptor ◽  
Characteristic Values

119Sn, 15N, 13C, and 1H NMR spectra were studied for [2-(dimethylaminomethyl)phenyl]stannanes, R1R2R3R4Sn or R1R2R24Sn, where R1, R2, and R3 are 1-butyl, Cl or Br, the same or different, and R4 is 2-(dimethylaminomethyl)phenyl. The occurrence of intramolecular interaction between the nitrogen and tin atoms was demonstrated based on changes in the characteristic values of the NMR parameters of these nuclides (δ(15N), δ(119Sn), J(119Sn,15N), and their interrelations, as well as on the relatively high values of the coupling constants 3J(119Sn,13C(CH2)).

scholarly journals 1H-NMR study of some new acetyl dimethylbiphenyls: unambiguous signal assignment for the methyl groups

1997 ◽  
Vol 13 (2) ◽  
pp. 125-129 ◽  
Author(s):  
Fadhil S. Kamounah ◽  
Salam J. Titinchi
Keyword(s):  
1H Nmr ◽  
Structure Elucidation ◽  
Nmr Spectra ◽  
Methyl Groups ◽  
H Nmr ◽  
Signal Assignment ◽  
Nmr Study

The abundance1H-NMR spectra of some new mono- and diacetyl compounds derived from 2,2′-dimethyl-, 3,3′-dimethyl-, and 4,4′-dimethylbiphenyls were recorded. Unambiguous signal assignment of the methyl groups of the aromatic biphenyl rings were made for the structure elucidation.

119Sn, 13C and 1H NMR Spectra of Tris(1-butyl)stannyl D-Glucuronate

1997 ◽  
Vol 62 (8) ◽  
pp. 1169-1176 ◽  
Author(s):  
Antonín Lyčka ◽  
Jaroslav Holeček ◽  
David Micák
Keyword(s):  
Chemical Shift ◽  
Carbonyl Group ◽  
1H Nmr ◽  
Equatorial Plane ◽  
Title Compound ◽  
Nmr Spectra ◽  
Hydroxyl Groups ◽  
Carboxylic Group ◽  
H Nmr ◽  
Oxygen Atoms

The 119Sn, 13C and 1H NMR spectra of tris(1-butyl)stannyl D-glucuronate have been measured in hexadeuteriodimethyl sulfoxide, tetradeuteriomethanol and deuteriochloroform. The chemical shift values have been assigned unambiguously with the help of H,H-COSY, TOCSY, H,C-COSY and 1H-13C HMQC-RELAY. From the analysis of parameters of 119Sn, 13C and 1H NMR spectra of the title compound and their comparison with the corresponding spectra of tris(1-butyl)stannyl acetate and other carboxylates it follows that in solutions of non-coordinating solvents (deuteriochloroform) the title compound is present in the form of more or less isolated individual molecules with pseudotetrahedral environment around the central tin atom and with monodentately bound carboxylic group. The interaction of tin atom with oxygen atoms of carbonyl group and hydroxyl groups of the saccharide residue - if they are present at all - are very weak. In solutions in coordinating solvents (hexadeuteriodimethyl sulfoxide or tetradeuteriomethanol), the title compound forms complexes with one molecule of the solvent. Particles of these complexes have a shape of trigonal bipyramid with the 1-butyl substituents in equatorial plane and the oxygen atoms of monodentate carboxylic group and coordinating solvent in axial positions.

scholarly journals 13C and 1H NMR Spectra of Synthetic (25R)-5α-Spirostanes

1999 ◽  
Vol 23 (1) ◽  
pp. 48-49
Author(s):  
Martín A. Iglesias Arteaga ◽  
Carlos S. Pérez Martinez ◽  
Roxana Pérez Gil ◽  
Francisco Coll Manchado
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
1H Nmr Spectra ◽  
H Nmr ◽  
C 23 ◽  
Main Effects ◽  
Nmr Signals

The assignment of 13C and 1H NMR signals of synthetic (25 R)-5α-spirostanes is presented; the main effects on chemical shifts due to substitution at C-23 are briefly discussed.

Zuordnung der 1H-NMR-Spektren von Depsiden, Depsidonen, Depsonen und Dibenzofuranen aus Flechten durch NOE-Differenzspektroskopie / Assignment of 1H NMR Spectra of Depsides, Depsidones, Depsones and Dibenzofurans from Lichens by NOE Difference Spectroscopy

1989 ◽  
Vol 44 (9) ◽  
pp. 1117-1123 ◽  
Author(s):  
Jasmin Jakupovic ◽  
Siegfried Huneck
Keyword(s):  
Methyl Ester ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Usnic Acid ◽  
Acid Methyl Ester ◽  
Difference Spectroscopy ◽  
H Nmr ◽  
Acid Methyl ◽  
Lichen Substances ◽  
Noe Difference Spectroscopy

The 1H NMR spectra of the following lichen substances have been correlated by NOE difference spectroscopy: atranorin, barbatic acid, diffractaic acid, nephroarctin, perlatolic acid, planaic acid methyl ester, pseudocyphellarin A, sphaerophorin (depsides), hypoprotocetraric acid, lobaric acid, pannarin, physodalic acid, psoromic acid, stictic acid (depsidones), picrolichenic acid (depsone), di-O-methyl-pannaric acid dimethylester, pannaric acid, porphyrilic acid, schizopeltic acid, strepsilin, and usnic acid (dibenzofurans).

scholarly journals Assessment of 1H NMR Spectroscopy for Specific Metabolite Fingerprinting of Angelica sinensis

2008 ◽  
Vol 3 (5) ◽  
pp. 1934578X0800300
Author(s):  
Dongmin Su ◽  
Jinglan Han ◽  
Shishan Yu ◽  
Hailin Qin
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr ◽  
1H Nmr Spectroscopy ◽  
Nmr Spectra ◽  
Authentic Sample ◽  
Angelica Sinensis ◽  
Metabolite Fingerprinting ◽  
H Nmr ◽  
Pure Compounds ◽  
Polar Extracts

The 1H NMR fingerprints of fractionated non-polar extracts (CSPD A) from the roots of Angelica sinensis of six different specimens were assigned by comparison with the 1H NMR spectra of the isolated pure compounds. The 1H NMR fingerprints showed exclusively characteristic resonance signals of the major constituents of the plant. The 1H NMR fingerprint established for an authentic sample of A. sinensis can be used for authenticating A. sinensis species.

Das 7,8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ5-phosphaspiro[4.4]nonanyl-Kation: Röntgenstrukturanalyse und temperaturabhängige 1H-NMR-Spektren: The 7, 8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ).5-phosphaspiro[4.4]nonanyl Cation: X-Ray Crystal Structure Determination and Variable 1H NMR Spectra

1992 ◽  
Vol 47 (6) ◽  
pp. 755-759 ◽  
Author(s):  
Thomas Kaukorat ◽  
Peter G. Jones ◽  
Reinhard Schmutzler
Keyword(s):  
Crystal Structure ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Crystal Structure Analysis ◽  
Acceptor Interaction ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Donor Acceptor

The 1H NMR spectrum of the spirophosphorane 3 at room temperature indicates dynamic behaviour of the cation. The low-temperature 1H NMR spectra of 3 exhibit two sets of doublets for the protons of the diastereotopic N(CH3)2 groups. The free enthalpy of activation for the dynamic process was determined (58.6 KJ/mole). In the reaction of 3 with sodium tetraphenylborate the crystalline compound, 4, involving the non-coordinating anion, [B(C6H5)4]-, was obtained. The X-ray crystal structure analysis of 4 reveals the presence of a five-membered ring, formally as a result of intramolecular donor-acceptor interaction between the nitrogen atom of the N(CH3)2 group and phosphorus. The geometry at phosphorus deviates somewhat from ideal trigonal bipyramidal.

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