1H and 13C NMR spectral studies of some 4H-3,1-benzoxazin-4-ones and their 2-acylaminobenzoic acid precursors

2000 ◽  
Vol 56 (6) ◽  
pp. 1079-1100 ◽  
Author(s):  
Alan G Osborne ◽  
Zia Goolamali
Keyword(s):  
13C Nmr ◽  
Spectral Studies ◽  
1H And 13C Nmr

scholarly journals Synthesis of ruthenium(II) carbonyl complexes with 2-monosubstituted and 1,2-disubstituted benzimidazoles

2009 ◽  
Vol 74 (10) ◽  
pp. 1085-1096 ◽  
Author(s):  
Naik Krishnamurthy ◽  
Narashimaiah Shashikala
Keyword(s):  
Elemental Analysis ◽  
13C Nmr ◽  
Spectral Studies ◽  
Carbonyl Complex ◽  
Carbonyl Complexes ◽  
Conductivity Measurements ◽  
1H And 13C Nmr

The reaction of the polymeric carbonyl complex [RuCl2(CO)2]x with 2-monosubstituted and 1,2-disubstituted benzimidazoles and 1,4-bis(benzimidazol- 2-yl)benzene (L9) in 2-methoxyethanol produces various coloured complexes of the formulae [Ru(CO)2Cl2(L)2]?xH2O (L = 1-(o-hydroxybenzyl)-2-(o-hydroxyphenyl)benzimidazole (L1), 1-(o-hydroxyphenyl)benzimidazole (L4), 1-(p-hydroxyphenyl)benzimidazole (L5), 1-(p-chlorobenzyl)-2-p-chlorophenyl) benzimidazole (L7), 1-[1-(dimethylamino)benzyl]-2-[1-(dimethylamino) phenyl]benzimidazole (L10), x = 0; L = 2-benzylbenzimidazole (L8), 1,4-bis(benzimidazol-2-yl)benzene (L9), x = 2; L = 1-(o-chlorobenzyl)-1-(o-chlorophenyl)benzimidazole (L6); x = 3), [Ru(CO)2Cl(L2)3]Cl?3H2O and [Ru(CO)2(L3)4]Cl2?3H2O (L2 = 1-(m-hydroxybenzyl)-2-(m-hydroxyphenyl)- benzimidazole; L3 = 1-(p-hydroxybenzyl)-2-(p-hydroxyphenyl)benzimidazole). The complexes were characterized by elemental analysis, conductivity measurements, as well as infrared, electronic, 1H- and 13C-NMR spectral studies.

ChemInform Abstract: 2,4-Dihalogenoquinolines. Synthesis, Orientation Effects and 1H and 13C NMR Spectral Studies.

ChemInform ◽  
2010 ◽  
Vol 25 (8) ◽  
pp. no-no
Author(s):  
A. G. OSBORNE ◽  
J. M. BULEY ◽  
H. CLARKE ◽  
R. C. H. DAKIN ◽  
P. I. PRICE
Keyword(s):  
13C Nmr ◽  
Spectral Studies ◽  
1H And 13C Nmr ◽  
Orientation Effects

1H and 13C NMR Spectral Studies on N-(Aryl)-Substituted Acetamides, C6H5NHCOCH3-iXi and 2/4-XC6H4NHCOCH3-iXi (where X = Cl or CH3 and i = 0, 1, 2 or 3)

2003 ◽  
Vol 58 (12) ◽  
pp. 801-806 ◽  
Author(s):  
B. Thimme Gowda ◽  
K. M. Usha ◽  
K. L. Jayalakshmi
Keyword(s):  
Chemical Shift ◽  
Benzene Ring ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Spectral Studies ◽  
Side Chain ◽  
1H And 13C Nmr ◽  
Methyl Group ◽  
Solution State

35 N-(Phenyl)-, N-(2/4-chlorophenyl)- and N-(2/4-methylphenyl)-substituted acetamides are prepared, characterised and their NMR spectra studied in solution state. The variation of the chemical shifts of the aromatic protons in these compounds follow more or less the same trend with changes in the side chain. The chemical shifts remain almost the same on introduction of Cl substituent to the benzene ring, while that of methyl group lowers the chemical shifts of the aromatic protons. But only 13C-1 and 13C-4 chemical shifts in these compounds are sensitive to variations of the side chain. The incremental shifts in the chemical shifts of the aromatic protons and carbons due to -COCH3−iXi or NHCOCH3−iXi groups in all the N-(phenyl)-substituted acetamides, C6H5NHCOCH3−iXi (where X = Cl or CH3 and i = 0, 1, 2 or 3) are calculated. These incremental chemical shifts are used to calculate the chemical shifts of the aromatic protons and carbons in all the N-(2/4-chlorophenyl)- and N-(2/4-methylphenyl)-substituted acetamides, in two ways. In the first way, the chemical shifts of aromatic protons or carbons are computed by adding the incremental shifts due to -COCH3−iXi groups and the substituents at the 2nd or 4th position in the benzene ring to the chemical shifts of the corresponding aromatic protons or carbons of the parent aniline. In the second way, the chemical shifts are calculated by adding the incremental shifts due to -NHCOCH3−iXi groups and the substituents at the 2nd or 4th position in the benzene ring to the chemical shift of a benzene proton or carbon, respectively. Comparison of the two sets of calculated chemical shifts of the aromatic protons or carbons of all the compounds revealed that the two procedures of calculation lead to almost the same values in most cases and agree well with the experimental chemical shifts.

scholarly journals Synthesis of Novel N-Acylhydrazones and Their C-N/N-N Bond Conformational Characterization by NMR Spectroscopy

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4908
Author(s):  
Rubina Munir ◽  
Noman Javid ◽  
Muhammad Zia-ur-Rehman ◽  
Muhammad Zaheer ◽  
Rahila Huma ◽  
...  
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
Room Temperature ◽  
Aromatic Aldehydes ◽  
Spectral Studies ◽  
13C Nmr Spectra ◽  
1H And 13C Nmr ◽  
Mass Spectral ◽  
Nmr Techniques ◽  
Ft Ir

In this article, a synthesis of N’-(benzylidene)-2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazides and their structural interpretation by NMR experiments is described in an attempt to explain the duplication of some peaks in their 1H- and 13C-NMR spectra. Twenty new 6-methyl-1H-pyrazolo[3,4-b]quinoline substituted N-acylhydrazones 6(a–t) were synthesized from 2-chloro-6-methylquinoline-3-carbaldehyde (1) in four steps. 2-Chloro-6-methylquinoline-3-carbaldehyde (1) afforded 6-methyl-1H-pyrazolo[3,4-b]quinoline (2), which upon N-alkylation yielded 2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetate (3). The hydrazinolysis of 3 followed by the condensation of resulting 2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazide (4) with aromatic aldehydes gave N-acylhydrazones 6(a–t). Structures of the synthesized compounds were established by readily available techniques such as FT-IR, NMR and mass spectral studies. The stereochemical behavior of 6(a–t) was studied in dimethyl sulfoxide-d6 solvent by means of 1H NMR and 13C NMR techniques at room temperature. NMR spectra revealed the presence of N’-(benzylidene)-2-(6-methyl-1H-pyrazolo[3,4-b]quinolin-1-yl)acetohydrazides as a mixture of two conformers, i.e., E(C=N)(N-N) synperiplanar and E(C=N)(N-N)antiperiplanar at room temperature in DMSO-d6. The ratio of both conformers was also calculated and E(C=N) (N-N) syn-periplanar conformer was established to be in higher percentage in equilibrium with the E(C=N) (N-N)anti-periplanar form.

2,4-Dihalogenoquinolines. Synthesis, orientation effects and 1H and 13C NMR spectral studies

1993 ◽  
pp. 2747 ◽  
Author(s):  
Alan G. Osborne ◽  
Jill M. Buley ◽  
Helen Clarke ◽  
Rachel C. H. Dakin ◽  
Paul I. Price
Keyword(s):  
13C Nmr ◽  
Spectral Studies ◽  
1H And 13C Nmr ◽  
Orientation Effects
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