13C-NMR spectra of benzenesulphonyl derivatives

1980 ◽  
Vol 45 (5) ◽  
pp. 1575-1580 ◽  
Author(s):  
Jaroslav Horyna ◽  
Antonín Lyčka ◽  
Dobroslav Šnobl

13C-NMR chemical shifts and 1J(CH) and 3J(CH) coupling constants have been determined for a series of C6H5SO2X derivatives (X = Cl, C6H5, Ona, OCH3, OC2H5, OC6H5, NH2, NHNH2, N(CH2)5, NHC6H5) in hexadeuteriodimethyl sulphoxide solutions, and the substituent shift values of benzene nucleus have been calculated for the individual SO2X groups,. These groups, carrying partial positive charge at the sulphur atom, have electron-acceptor effects on the benzene nucleus, and increasing electron-donor character of the substituent X is connected with a proportional increase of mesomeric acceptor influence on the benzene nucleus and with increase in absolute values of 1J(CH).

1980 ◽  
Vol 45 (10) ◽  
pp. 2766-2771 ◽  
Author(s):  
Antonín Lyčka

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.


1984 ◽  
Vol 39 (7) ◽  
pp. 915-920 ◽  
Author(s):  
Herbert Meier ◽  
Thomas Molz ◽  
Heinz Kolshorn

The 1H and 13C NMR data of thiophene 1,1-dioxide (3) and related compounds, especially of the precursor 2 and the consecutive product 5 are evaluated by computer simulation and multiple resonance. Chemical shifts and coupling constants reveal that 3 has the character of a cyclic diene. Diatropic or paratropic effects can be excluded.


1987 ◽  
Vol 42 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Udo Kunze ◽  
Rolf Tittmann

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.


1979 ◽  
Vol 34 (11) ◽  
pp. 1606-1611 ◽  
Author(s):  
W. Winter ◽  
K.-P. Zeller ◽  
S. Berger

Abstract A low temperature X-ray study of the enol of benzoylacetone indicates fixed positions of the C and O atoms within the enolic ring system and an extensive bond delocalisation over these atoms. The distribution of electron density between the two oxygen atoms shows that the enolic hydrogen is spread over a wide range. This is in accordance with a structural model proposed by de la Vega, whereupon the C and O atoms are kept fixed in their average positions during a tunneling process of the hydrogen between the two oxygen atoms. With this conception, the chemical shifts in the 17O and 13C NMR spectra, the 13C13C spin coupling constants and the temperature independance of these values can be explained.


1991 ◽  
Vol 46 (3-4) ◽  
pp. 177-182 ◽  
Author(s):  
Hans-W. Rauwald ◽  
Deo-D. Niyonzima

From the leaf exudate of Aloe lateritia ENGLER the C-glucosyl com pounds homonataloin, aloeresin A and aloesin (synon. aloeresin B) were isolated together with the anthraquinone nataloeem odin-8-methylether and spectroscopically identified. Hom onataloin, widely distributed in Aloe species, was separated into homonataloin A and B by combined TLC and DCCC. In their 1 D and 2D 1H NMR spectra only the shifts of the 2′-hydroxyl protons of both glucosyl residues differ significantly, indicative of 10 S (A) resp. 10 S (B) configurations. In both com pounds the anthrone is in β-position of the D-glucopyranosyl, as determined by the large coupling constants of the anomeric protons. The 13C NMR signals are unambiguously assigned by the use of DEPT, APT and gated-decoupling methods. Only the chemical shifts of C -11 and C -14 show significant differences between both diastereomers due to the adjacent 2′-sugar hydroxyls. The two homonataloins differ mostly in optical rotation and circulardichroism due to different configurations at C - 10 of the anthrone part. The absolute configurations of the diastereomers are determined by correlation of their CD spectra with the CD spectra of the structural analogues 7-hydroxyaloins A and B, which shows that hom onataloin A is the 10 S, 1′S-compound and that homonataloin B has 10 R, 1′S-configuration.


1981 ◽  
Vol 36 (8) ◽  
pp. 1017-1022 ◽  
Author(s):  
Herbert Meier ◽  
Johannes Zountsas ◽  
Oswald Zimmer

Abstract A 1H and 13C NMR spectroscopical study is performed on the basis of 37 1,2,3-selena-diazoles. Besides the discussion of chemical shifts and coupling constants of 1H and 13C, selenium satellites were measured providing 1H77 Se and 13C77 Se coupling constants.


1979 ◽  
Vol 57 (23) ◽  
pp. 3168-3170 ◽  
Author(s):  
Henk Hiemstra ◽  
Hendrik A. Houwing ◽  
Okko Possel ◽  
Albert M. van Leusen

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.


1990 ◽  
Vol 55 (5) ◽  
pp. 1193-1207 ◽  
Author(s):  
Jaroslav Holeček ◽  
Antonín Lyčka ◽  
Karel Handlíř ◽  
Milan Nádvorník

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.


1979 ◽  
Vol 18 (1) ◽  
pp. 139-143 ◽  
Author(s):  
M.H.A. Elgamal ◽  
N.H. Elewa ◽  
E.A.M. Elkhrisy ◽  
Helmut Duddeck

RSC Advances ◽  
2015 ◽  
Vol 5 (46) ◽  
pp. 36858-36864 ◽  
Author(s):  
Yang Li

The 13C NMR spectra and vicinal proton–proton coupling constants of two tricyclic macrolactone natural products were analyzed using computational methods, which resulted in their structural revisions.


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