scholarly journals Peculiarities of 13C NMR Spectra of Benzoylformic Acid and its Esters. 1. Benzoyl Fragment

2009 ◽  
Vol 3 (2) ◽  
pp. 83-90
Author(s):  
Volodymyr Mizyuk ◽  
◽  
Volodymyr Shibanov ◽  
Keyword(s):  
Chemical Shift ◽  
General Formula ◽  
13C Nmr ◽  
Nmr Spectra ◽  
13C Nmr Spectra ◽  
Phenyl Fragment ◽  
Characteristic Values

Peculiarities of 13C NMR spectra of benzoyl fragment of benzoylformic acid and its esters have been investigated and characteristic values of a chemical shift of all five types of fragment atom have been examined. Similar parameters of other benzoyl-containing compounds by general formula Bz–X (X = H, NR2, OR, SR, Cl, Br), as well as those of compounds Bz–C (L)(M)(N) have been compared. It has been shown that spectral peculiarities of a benzoylformates phenyl fragment are defined by the carbonyl, not by the carbalkoxyl group.

Reply to the comment on “novel substituent effects in 1H and 13C NMR spectra of 4- and 4′-substituted N-benzylideneanilines.” problems of 1H chemical shift measurement

1975 ◽  
Vol 16 (43) ◽  
pp. 3697-3700
Author(s):  
Naoki Inamoto ◽  
Shozo Masuda ◽  
Katsumi Tokumaru ◽  
Masayuki Yoshida ◽  
Youko Tamura ◽  
...  
Keyword(s):  
Chemical Shift ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Substituent Effects ◽  
13C Nmr Spectra ◽  
Shift Measurement ◽  
1H And 13C Nmr

Incorporation of Chlorinated Anilines into Lignin

1981 ◽  
Vol 36 (9-10) ◽  
pp. 714-720 ◽  
Author(s):  
K. T. v. d. Trenck ◽  
D. Hunkier ◽  
H. Sandermann
Keyword(s):  
Chemical Shift ◽  
1H Nmr ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chain Structure ◽  
Coniferyl Alcohol ◽  
13C Nmr Spectra ◽  
Nmr Chemical Shift ◽  
Phenyl Propanoid

Abstract Coniferyl Alcohol, Peroxidase, Lignin, 4-Chloroaniline, 3,4-Dichloroaniline Lignin was formed in vitro by the peroxidase/hydrogen peroxide mediated polymerization of coniferyl alcohol. In the presence of [14C]4-chloroaniline or [14C]3,4-dichloroaniline copolymeri­ zation occurred with incorporation rates of about 45 mol%. Co-elution of UV-absorbing material (reflecting lignin) and of incorporated radioactivity was observed on a calibrated column of Sephadex LH-60. This method indicated a broad molecular weight distribution of the copolymers with values of between about 20000 and 1000. Most of the copolymer products had apparent molecular weights near 1000.The 1H-NMR and 13C-NMR spectra of the copolymers were compared with those of in vitro lignin. The copolymer spectra showed a relative increase in aromatic peaks and a relative decrease in most of the typical lignin peaks. Three peaks indicative of a new type of phenyl-propanoid side-chain structure were detected in the 'H-NMR and 13C-NMR spectra of the copolymers. The corresponding 1H-NMR chemical shift values were 4.75 ppm (a-C-H), 4.40 ppm (β-C-H) and 3.70/3.50 ppm (y-C-H2). The 13C-NMR chemical shift values were 56.9 ppm (a-C), 84.3 ppm (β-C) and 60.0 ppm (y-C). These peaks were attributed to a 3-aryl-3-anilino-2-aryloxy-propanol-1 structure in the copolymers by analysis of coupling patterns and by comparison with spectral reference data.The NMR-results and experiments with catalase and inhibitors suggested that a major mechanism of copolymerization consisted of a nucleophilic addition of the anilines to the benzylic ar-carbon of lignol quinone-methide intermediates.

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