NMR-spektroskopische Untersuchung des Problems der Valenzisomerie zwischen 1,2-Dithiin und (Z)-But-2-en-1,4-dithion / NMR Spectroscopic Investigation Concerning the Problem of Valence Isomerism between 1,2-Dithiine and (Z)-But-2-ene-1,4-dithione

1988 ◽  
Vol 43 (5) ◽  
pp. 605-610 ◽  
Author(s):  
Reiner Radeglia ◽  
Helmut Poleschner ◽  
Werner Schroth
Keyword(s):  
Nmr Spectra ◽  
Chemical Shifts ◽  
2D Nmr ◽  
Ring Structure ◽  
Coupling Constants ◽  
Nmr Parameters ◽  
Spectrum Simulation ◽  
2D Nmr Spectra ◽  
Transoid Conformation ◽  
C Nmr

3,6-Diaryl-1,2-dithiines and their precursors, (Z,Z)-1,4-bis(organylthio)-buta-1,3-dienes, are investigated by 1H and 13C NMR spectroscopy. The chemical shifts and coupling constants, which are relevant to the investigated problem, are determined and assigned, respectively, by different techniques (shift increments, spectrum simulation, heteronuclear 2D J-resolved and heteronuclear shift correlated 2D NMR spectra, anomalous off-resonance splittings and selective decoupling experiments). The NMR parameters are discussed in relation to the molecular structure. The 13C shift values prove the ring structure of 1,2-dithiines and exclude existence of the valence isomer (Z)-but-2-ene-1,4-dithione (absence of thiocarbonyl resonances). The vicinal 1H,1H coupling constants of the C4 unit of the investigated compounds verify (1) the (Z,Z) configuration of the organylthio groups in 1,4 position of butadiene, (2) the s-transoid conformation of acyclic butadienes and (3) the forced s-cis structure in the cyclic 1,2-dithiines.

scholarly journals 1H and13C NMR spectroscopic studies of half-esters from monohydrolysis of dialkyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylates

2004 ◽  
Vol 18 (3) ◽  
pp. 469-483
Author(s):  
Yoshikazu Hiraga ◽  
Satomi Niwayama
Keyword(s):  
Nmr Spectra ◽  
Chemical Shifts ◽  
2D Nmr ◽  
Spectroscopic Studies ◽  
Carboxyl Group ◽  
1H And13c Nmr ◽  
Nmr Chemical Shifts ◽  
2D Nmr Spectra ◽  
Spectral Assignment ◽  
C Nmr

The structures of the half-esters from the monohydrolysis of (exo,exo)-, (endo,endo)-, and (endo,exo)-dialkyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylates were determined by1H and13C NMR as well as 2D NMR spectra, and the complete spectral assignment has been made. After conversion of one of the carboalkoxy groups to a carboxyl group, different tendencies were observed for the differences in1H and13C NMR chemical shifts between half-esters and the corresponding diesters.

13C NMR spectra of sodium naphthalenesulphonates

1985 ◽  
Vol 50 (8) ◽  
pp. 1852-1861 ◽  
Author(s):  
Dobroslav Šnobl ◽  
Antonín Lyčka ◽  
Jaroslav Horyna
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Deuterium Oxide ◽  
Coupling Constants ◽  
13C Nmr Spectra ◽  
Nmr Parameters ◽  
Measured Effect ◽  
C Nmr

13C NMR spectra of thirteen sodium naphthalenesulphonates have been measured in deuterium oxide. The 13C chemical shifts have been assigned, and the nJ(13CH) coupling constants have been measured. Effect of SO3(-) group on the 13C NMR parameters is discussed.

Carbon-13 and nitrogen-14 NMR spectra of 1-(substituted phenyl)pyridinium salts

1980 ◽  
Vol 45 (10) ◽  
pp. 2766-2771 ◽  
Author(s):  
Antonín Lyčka
Keyword(s):  
Heavy Water ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Pyridinium Salts ◽  
Nmr Signals ◽  
C Nmr

The 13C and 14N NMR spectra of 1M solutions of 1-(substituted phenyl)pyridinium salts (4-CH3, 4-OCH3, H, 4-Cl, 4-Br, 4-I, 3-NO2, 4-NO2, 2,4-(NO2)2 (the 13C NMR only)) have been measured in heavy water at 30 °C. The 13C and 14N chemical shifts, the 1J(CH) coupling constants, some 3J(CH) coupling constants, and values of half-widths Δ 1/2 of the 14N NMR signals are given. The 13C chemical shifts of C(4) correlate with the σ0 constants (δC(4) = (1.79 ± 0.097) σ0 + (147.67 ± 0.041)), whereas no correlation of the nitrogen chemical shifts with the σ constants has been found. The half-widths Δ 1/2 correlate with the σ0 constants (Δ 1/2 = (76.2 ± 4.9) σ0 + (106.4 ± 2.2)) except for 1-phenylpyridinium chloride.

E-Homolupane Derivatives Substituted in Position 17 and 22a. 1H NMR, 13C NMR and IR Spectra

1995 ◽  
Vol 60 (4) ◽  
pp. 619-635 ◽  
Author(s):  
Václav Křeček ◽  
Stanislav Hilgard ◽  
Miloš Buděšínský ◽  
Alois Vystrčil
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Coupling Constants ◽  
Side Chain ◽  
Oxidation Reactions ◽  
H Nmr ◽  
Complete Assignment ◽  
Nmr Techniques ◽  
Intramolecular Association ◽  
C Nmr

A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy. The kind of intramolecular association of the 17α-hydroxy group was studied in connection with modification of the side chain and substitution in position 22a. Complete assignment of the hydrogen signals and most of the coupling constants was accomplished using a combination of 1D and 2D NMR techniques. The 1H and 13C NMR spectra are discussed.

scholarly journals Reactions of 3-(p-substituted-phenyl)-5-chloromethyl-1,2,4-oxadiazoles with KCN leading to acetonitriles and alkanes via a non-reductive decyanation pathway

2018 ◽  
Vol 14 ◽  
pp. 3011-3017
Author(s):  
Akın Sağırlı ◽  
Yaşar Dürüst
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Synthetic Route ◽  
X Ray ◽  
H Nmr ◽  
2D Nmr Spectra ◽  
Tof Ms ◽  
C Nmr

The present work describes an unfamiliar reaction of 5-(chloromethyl)-3-substituted-phenyl-1,2,4-oxadiazoles with KCN affording trisubstituted 1,2,4-oxadiazol-5-ylacetonitriles and their parent alkanes, namely, 1,2,3-trisubstituted-1,2,4-oxadiazol-5-ylpropanes. To the best of our knowledge, the current synthetic route leading to decyanated products will be the first in terms of a decyanation process which allows the transformation of trisubstituted acetonitriles into alkanes by the incorporation of KCN with the association of in situ-formed HCN and most likely through the extrusion of cyanogen which could not be detected or isolated. In addition, the plausible mechanisms were proposed for both transformations. The structures of the title compounds were identified by means of IR, 1H NMR, 13C NMR, 2D NMR spectra, TOF–MS and X-ray measurements.

Phosphinsubstituierte Chelatliganden, XXIII [1] Darstellung und NMR-Spektren von Alkyl-arylphosphinothioformamiden, R(Ph)PC(S)NHMe / Phosphine-Substituted Chelate Ligands, XXIII [1] Synthesis and NMR Spectra of Alkyl-arylphosphinothioformamides, R(Ph)PC(S)NHMe

1987 ◽  
Vol 42 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Udo Kunze ◽  
Rolf Tittmann
Keyword(s):  
Chemical Shift ◽  
Linear Correlation ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Cone Angle ◽  
Coupling Constants ◽  
Methyl Isothiocyanate ◽  
Signal Sets ◽  
The Asymmetry ◽  
C Nmr

Abstract A series of alkyl-arylsubstituted N-methyl phosphinothioformamides, R(Ph)PC(S)NHMe (2 a-g), with varying bulkiness of the alkyl rest was synthesized from the racemic secondary phosphines 1a-g and methyl isothiocyanate. 1H and 13C NMR spectra of 2a−g reveal signal sets of diastereotopic nuclei due to the asymmetry of the molecule. The chemical shift and coupling constants were confirmed by simulation in case of 2b, c. The vicinal 31P−13C couplings of the menthyl and neomenthyl compounds 2f, g show an "anti-Karplus" behaviour (3J(gauche) > 3J(trans)) and allow the conformational assignment of the alicyclic group. The 31P chemical shifts of 2a−d give a linear correlation with the cone angle of the alkyl substituents quoted from literature.

scholarly journals Protolysis and Complex Formation of Organophosphorus Compounds—Characterization by NMR-Controlled Titrations

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3238 ◽  
Author(s):  
Hägele
Keyword(s):  
Dissociation Constants ◽  
Organophosphorus Compounds ◽  
Chemical Shifts ◽  
2D Nmr ◽  
Coupling Constants ◽  
Phosphonic Acids ◽  
Specific Chemical ◽  
Hyphenated Technique ◽  
Aminophosphonic Acids ◽  
2D Nmr Spectra

Phosphonic acids, aminophosphonic acids, and phosphonocarboxylic acids are characterized by an advanced hyphenated technique, combining potentiometric titration with NMR spectroscopy. Automated measurements involving 13C, 19F and 31P nuclei lead to “pseudo 2D NMR” spectra, where chemical shifts or coupling constants are correlated with analytical parameters. Dissociation constants, stability constants, dynamic and specific chemical shifts are determined. Macroscopic and microscopic dissociation equilibria are discussed.

scholarly journals Carbon-13 nuclear magnetic resonance spectra of oxazoles

1979 ◽  
Vol 57 (23) ◽  
pp. 3168-3170 ◽  
Author(s):  
Henk Hiemstra ◽  
Hendrik A. Houwing ◽  
Okko Possel ◽  
Albert M. van Leusen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Proton Coupling ◽  
Nuclear Magnetic Resonance Spectra ◽  
C Nmr ◽  
Magnetic Resonance Spectra ◽  
Nuclear Magnetic

The 13C nmr spectra of oxazole and eight mono- and disubstituted derivatives have been analyzed with regard to the chemical shifts and the various carbon–proton coupling constants of the ring carbons. The data of the parent oxazole are compared with thiazole and 1-methylimidazole.

13C and 119Sn NMR spectra of diphenyl- and dibenzyltin(IV) compounds and their complexes

1990 ◽  
Vol 55 (5) ◽  
pp. 1193-1207 ◽  
Author(s):  
Jaroslav Holeček ◽  
Antonín Lyčka ◽  
Karel Handlíř ◽  
Milan Nádvorník
Keyword(s):  
Internal Structure ◽  
Coordination Sphere ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Spectral Parameters ◽  
The Real ◽  
119Sn Nmr ◽  
C Nmr

13C and 119Sn NMR spectra of diphenyl- and dibenzyltin(IV) compounds have been studied in solutions of coordinating and non-coordinating solvents. Regions of values of the δ(119Sn) chemical shifts have been determined which characterize individual types of coordination of the central tin atom. The values of 13C NMR spectral parameters, the δ(13C) chemical shifts and nJ(119Sn, 13C) coupling constants, have been used to describe the real shapes of coordination sphere of the central tin atom and to discuss the internal structure of the organic substituents and of the nature of their bonding linkage to the tin atom.

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