15N, 13C, and 1H NMR Spectra of Azo and Hydrazo Compounds Derived from 1,3,3-Trimethyl-2-methylidene-2,3-dihydroindole (Fischer Base)

1998 ◽  
Vol 63 (7) ◽  
pp. 1012-1020 ◽  
Author(s):  
Antonín Lyčka ◽  
Josef Jirman ◽  
Alois Koloničný
Keyword(s):  
Double Bond ◽  
Hydrochloric Acid ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Azo Compounds ◽  
Passive Component ◽  
Geometric Isomers ◽  
H Nmr ◽  
Fischer Base ◽  
Hydrazone Form

The 15N, 13C, and 1H NMR spectra were measured for azo and hydrazo compounds derived from 1,3,3-trimethyl-2-methylidene-2,3-dihydroindole (Fischer base), which is a passive component with a terminal methylidene group. Products prepared by coupling in hydrochloric acid exist in the corresponding hydrazone form as the E-isomers. Neutralization gives a mixture of two isomeric azo compounds which differ in the arrangement at the C(2)=C(10) double bond. This mixture was alkylated with methyl iodide to obtain the =N-N(CH3)- hydrazone derivatives. The geometric isomers were resolved based on the NOESY approach and the stereospecific behaviour of the 2J(15N,13C) coupling constants was studied for the 15N-labelled compounds.

Derivatives of 5α-androstan-3α- and 3β-ol with acrylonitrile side chain

1991 ◽  
Vol 56 (12) ◽  
pp. 2906-2916 ◽  
Author(s):  
Vladimír Pouzar ◽  
Hana Chodounská ◽  
Ivan Černý ◽  
Pavel Drašar
Keyword(s):  
Double Bond ◽  
Nmr Spectra ◽  
Sodium Hydride ◽  
Coupling Constants ◽  
Side Chain ◽  
H Nmr ◽  
Derivatives Of

Aldehydes II - III were reacted with diethyl cyanomethylphosphonate and sodium hydride in 1,2-dimethoxyethane to give the respective pairs of unsaturated nitriles IVa and Va, VIa and VIIa, and VIIIa and IXa differing in configuration at the 20(21)-double bond. The pure isomers were obtained by chromatography on alumina, and the configuration at the double bond in them has been established on the basis of the coupling constants J(20, 21) in their 1H NMR spectra. Nitriles IVa - VIIa and IXa were converted via the corresponding hydroxy derivatives into hemisuccinates IVd - VIId and IXd, and into β-D-glucosides IVe - VIIe and IXe.

Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

1981 ◽  
Vol 46 (8) ◽  
pp. 1913-1929 ◽  
Author(s):  
Bohdan Schneider ◽  
Pavel Sedláček ◽  
Jan Štokr ◽  
Danica Doskočilová ◽  
Jan Lövy
Keyword(s):  
Ethylene Glycol ◽  
Vibrational Spectra ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Conformational Structure ◽  
Infrared And Raman Spectra ◽  
H Nmr ◽  
Liquid States ◽  
Crystalline Forms ◽  
C Nmr

It was found that three crystalline forms of ethylene glycol dibenzoate can be prepared. Infrared and Raman spectra of these three forms, as well as of the glassy and liquid states, were measured. From 3JHH coupling constants obtained by analysis of the 13C satellite band of the -CH2- group in 1H NMR spectra, and from the 3JCH coupling constants of the -CO.O.CH2- fragment obtained by analysis of the carbonyl band in 13C NMR spectra it was found that in the liquid state the -CH2-CH2- group exists predominantly in the gauche conformational structure, and the bonds C-O-C-C assume predominantly a trans orientation. The results of the analysis of NMR and vibrational spectra were used for the structural interpretation of conformationally sensitive bands in vibrational spectra of ethylene glycol dibenzoate.

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.

Deuterium Quadrupolar Parameters from 1H and 2H NMR Spectra for Pyridine-d5, Benzonitrile-d5 and Chlorobenzene-d5 Using Liquid Crystal Solvents

1986 ◽  
Vol 41 (1-2) ◽  
pp. 431-435 ◽  
Author(s):  
R. Ambrosetti ◽  
D. Catalano ◽  
C. Forte ◽  
C. A. Veracini
Keyword(s):  
Liquid Crystal ◽  
Nmr Spectra ◽  
Order Parameters ◽  
Dipolar Couplings ◽  
Coupling Constants ◽  
2H Nmr ◽  
H Nmr ◽  
Quadrupolar Coupling ◽  
Asymmetry Parameters ◽  
Quadrupolar Splittings

T he quadrupolar coupling constants (DQCC) and the asymmetry parameters (η) for the ortho, meta and para deuterons in pyridine-d5, benzonitrile-d5 and chlorobenzene-d5 were determined by NMR spectroscopy in oriented phases. The 1H and 2H NMR spectra were recorded in the following solutions in liquid crystal solvents: pyridine + pyridine-d5 in PCH , in ZLI 1167 and in EBBA; benzonitrile + benzonitrile-d5 and chlorobenzene + chlorobenzene-d5 in the same solvents.The order parameters of the non-deuterated solutes in the various solutions were calculated using the dipolar couplings of the proton spectra and the rα structures taken from the literature. The same order parameters were assumed to describe also the orientation of the deuterated solute in the corresponding solutions.Each 2H spectrum yielded three quadrupolar splittings for the three different deuterated positions in the labelled solute. The splittings from the three different solutions of the same solute, together with the order parameters and the rα structure, were used to determine DQCC and η of the ortho, meta and para deuterons (Pyridine-d5: DQCCortho= 183(1) kHz, ηortho = 0.030(5), DQCCmeta = 185(1) kHz, ηmeta = 0.030(10), DQCCpara = 188(6) kHz, ηpara = 0.01(5). Benzonitrile-d5: DQCCortho = 171(12) kHz, ηortho = 0.07(3), DQCCmeta = 175(12) kHz, ηmeta = 0.05(3), DQCCpara = 176(4) kHz, ηpara = 0.10(7). Chlorobenzene-d5: DQCCortho = 180(2) kHz, ηortho = 0.06(1), DQCCmeta = 174(2) kHz, ηmeta = 0.09(3), DQCCpara= 182(4) kHz, ηPara = 0.06(4)). The results are discussed, as well as the limits and possibilities of the method used.

sHigh resolution 1H nuclear magnetic resonance studies of a flavine and its product with MoCl4

1977 ◽  
Vol 55 (4) ◽  
pp. 575-582 ◽  
Author(s):  
T. Roberie ◽  
N. S. Bhacca ◽  
J. Selbin
Keyword(s):  
Aqueous Solution ◽  
Nuclear Magnetic Resonance ◽  
Binding Sites ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Side Chain ◽  
Magnetic Resonance Studies ◽  
H Nmr ◽  
Metal Atoms ◽  
1H Nuclear Magnetic Resonance

The high resolution 1H nmr spectra of the substituted flavine, 3-N-methyltetraacetylriboflavine (3-Me-TARF), and its non-aqueous solution complexes with Gd(fod)3, Eu(fod)3, MoCl4, and MoCl4•2CH3(CH2)2CN, were studied in order to try to discern the binding sites of the flavine as it attaches to the molybdenum. Evidence was found that all three metal atoms, Gd(III), Eu(III), and Mo(IV), are attached in solution not only by the primary binding (chelating) sites of the flavine, viz., the O-4 and N-5 atoms, but also by an acetyl oxygen atom, at the C-4′ site of the ribityl side chain. 300 MHz spectra of the 3-Me-TARF have permitted the coupling constants for the side chain methine and methylene protons to be obtained.

Hétérobicycles oxygénés. Synthèse d'alkyl-3,6,8-trioxabicyclo[3.2.1]octanes et d'alkyl-3,7,9 et -4,7,9-trioxabicyclo[4.2.1]nonanes

1978 ◽  
Vol 56 (17) ◽  
pp. 2292-2300 ◽  
Author(s):  
Pierre Calinaud ◽  
Jacques Gelas
Keyword(s):  
Double Bond ◽  
Carbon Atom ◽  
Nmr Spectra ◽  
Membered Ring ◽  
Coupling Constants ◽  
Basic Medium ◽  
Main Interest ◽  
Proton Coupling ◽  
Geminal Proton

The cyclization in a basic medium of 2 (or 4)-chloroalkyl-4 (or 2) -hydroxyalkyl-1,3-dioxolanes leads to bicyclic acetals, the 3,6,8-trioxabicyclo[3.2.1]octanes, which are useful intermediates for synthesis, yielding notably functionalized 1,4-dioxanes. The nmr spectra of these heterobicyclics were studied. The geminal proton coupling constants permit oneto distinguish between five- and six-membered rings and the determination of couplings over several bonds (4J and 5J) yields information concerning the conformation of the model bicyclics.Two isomeric series of alkylated bicyclic acetals (3,7,9- and 4,7,9-trioxabicyclo[4.2.1]nonanes) are accessible by the following routes: (a) the intramolecular addition of a 4-hydroxy-alkyl group to the ethylenic double bond on the carbon atom a to C-2 in the 1,3-dioxolanes; (b) the dechlorohydration of 2-chloromethyl-4-hydroxyalkyl-1,3-dioxolanes; (c) the dehydration of dioxolane-diols. The main interest in these heterobicyclics is to prepare a seven-membered ring and to be able to prepare functionalized 1,4-dioxepanes. [Journal translation]

Notizen: Geminal Coupling Constants 2.J(15N13C) in 2-Substituted Pyridines, Measured by Hahn-Echo Extended (HEED) Pulse Sequences

1993 ◽  
Vol 48 (10) ◽  
pp. 1433-1436
Author(s):  
Bernd Wrackmeyer ◽  
Gerald Kehr
Keyword(s):  
High Resolution ◽  
Nmr Spectra ◽  
Pulse Sequences ◽  
Coupling Constants ◽  
Positive Sign ◽  
Two Dimensional ◽  
H Nmr ◽  
Substituted Pyridines ◽  
Geminal Coupling

Coupling constants 2J(15N13CR) and nJ(15N1HR) in 2-substituted pyridines [R = Me (1), CH=CH2 (2), C≡CH (3), C(O)H (4), C(O)Me (5)] have been measured by using Hahn-echo extended (HEED) pulse sequences for one- (1 D) and two-dimensional (2D) 13C/1H NMR (HEED-INEPT, HEED-HETCOR). The magnitude of |2J(15N13CR)| is hardly affected by the hybridization of 13CR. 15N NMR spectra, measured under conditions of ultra high resolution (UHR) confirm the values 2J(15N13CR). 2D 13C/1H HEED-HETCOR experiments show that the sign of 3J(15Ν1HR) is negative in 1, whereas the coupling constants 3J(15N1HR) in 4 and 4J(15N1HR) in 3 have a positive sign

The 1H NMR spectra and the conformation of 1,6-anhydro-β-D-hexopyranoses and their triacetates

1979 ◽  
Vol 44 (6) ◽  
pp. 1949-1964 ◽  
Author(s):  
Miloš Buděšínský ◽  
Tomáš Trnka ◽  
Miloslav Černý
Keyword(s):  
Nmr Spectra ◽  
Chemical Shifts ◽  
Shift Reagent ◽  
Point Of View ◽  
Coupling Constants ◽  
Lanthanide Shift Reagent ◽  
Pyranose Ring ◽  
H Nmr ◽  
Vicinal Coupling Constants

The 1H NMR spectra of 1,6-anhydro-β-D-hexopyranoses and their triacetates, measured in hexadeuteriodimethyl sulfoxide or deuteriochloroform, confirmed the existence of these compounds in 1C4(D) conformations, with the pyranose ring partly planarized in dependence on the configuration of the substituents in positions C(2), C(3) and C(4). The effects of the substituents on the chemical shifts and the adjusted relationship for the dependence of vicinal coupling constants on the torsion angle are discussed in detail from the point of view of the determination of the configuration and the conformation of 1,6-anhydro-β-D-hexopyranoses and their derivatives. The 1H NMR spectra of triacetates were also measured in the presence of the lanthanide shift reagent, tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione) europium (III) [Eu.(FOD)3].

Wolfram-Carbonylkomplexe mit Stickstoff-Wasserstoff-Liganden [1] / Tungsten Carbonyl Complexes with Nitrogen Hydride Ligands [1]

1978 ◽  
Vol 33 (5) ◽  
pp. 542-553 ◽  
Author(s):  
Dieter Sellmann ◽  
Alfred Brandl ◽  
Ralf Endeil
Keyword(s):  
Ligand Exchange ◽  
Nmr Spectra ◽  
Base Catalysis ◽  
Coupling Constants ◽  
Carbonyl Complexes ◽  
H Nmr ◽  
Nitrogen Hydride ◽  
Tungsten Carbonyl ◽  
Synthesis Properties ◽  
Hydride Ligands

Abstract Synthesis, properties and reactions of [(OC)5W]2N2H2, [(OC)5W]2N2H4, (OC)5WN2H4, (OC)5WNH3, [(OC)4PØ3W]2N2H4, [(OC)4PØ3WN2H4], [(OC)5W-N2H2-W(CO)4PØ3], [(OC)5W-N2H2-W(CO)4P(CH3)3] and [(OC)5WNHCH3NHC6H5] are reported. The hydrazine complexes are synthesized by ligand exchange from the corresponding tetra-hydrofuran complexes. Oxidation by various oxidizing agents yields the diazene complexes, in most cases very low yields. Substitution of CO by phosphanes leads to reduced stability of the compounds. All complexes undergo base catalysed H-D exchange yielding the corresponding ND derivatives; the diazene complexes show a much faster exchange than the corresponding hydrazine and ammonia complexes, which is explained by the higher acidity of the N2H2 protons. The diazene complexes disproportionate under base catalysis to hydrazine and dinitrogen compounds, the latter of which loose the N2 ligand immediately. The diazene ligand of [(OC)5W]2N2H2 cannot be alkylated by reactions with (CH3)2SO4, LiCH3 or CH2N2; instead, LiCH3 as well as CH2N2 cause disproportionation to N2H4 and N2 complexes. UV irradiation of [(OC)5W]2N2H2 in THF leads to substitution of CO by THF. The THF complexes can be converted to the phosphane substituted diazene complexes. The IR, UV-VIS and 1H NMR spectra of the (OC)5W complexes are nearly identical to those of the analogous Cr and Mo compounds. The unsymmetrical phosphane diazene complexes, however, show a quartet of the N2H2 protons in the 1H NMR spectra with coupling constants of 25-26 Hz for the protons on the NN double bond. This value points to a trans configuration of the diazene ligand and its complexes respectively.

Analysis of 1H-NMR spectra of cinnamaldehyde type model substances of lignin

1980 ◽  
Vol 45 (2) ◽  
pp. 330-334 ◽  
Author(s):  
Tibor Liptaj ◽  
Milan Remko ◽  
Ján Polčin
Keyword(s):  
Double Bond ◽  
Nmr Spectra ◽  
Side Chain ◽  
Type Model ◽  
Stable Conformer ◽  
Spectra Analysis ◽  
H Nmr ◽  
Nmr Data ◽  
Lignin Model ◽  
Model Substances

1H-NMR spectra of the following lignin model substances have been analyzed: cinnamaldehyde, 2-methoxycinnamaldehyde, 3-methoxycinnamaldehyde, 4-methoxycinnamaldehyde, 3,4-dimethoxycinnamaldehyde, 3-methoxy-4-hydroxycinnamaldehyde and 3,4,5-trimethoxycinnamaldehyde. From the NMR spectra analysis it follows that the studied compounds exist in solutions as trans isomers. Theoretical (PCILO) calculations in agreement with the NMR data have shown that the more stable conformer has trans orientation of C=O group with respect to the double bond of the conjugated side chain.

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