scholarly journals Synthesis and isomerism of 2-benzoyl-5,12-dimethoxy-3-heteryl-1,2,3,4-tetrahydronaphtho[2,3-g]phthalazine-6,11-diones

2021 ◽  
pp. 32-39
Author(s):  
A.I. Karkhut ◽  
◽  
Kh.B. Bolibrukh ◽  
O. Khoumeri ◽  
O.O. Vashchenko ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Structure Modeling ◽  
Dft Methods ◽  
Simulation Results ◽  
Noesy Spectra

The cyclocondensation of the bielectrophile 2,3-bis(bromomethyl)-1,4-dimethoxyanthracene-9,10-dione with several heteroyl-benzyl hydrazides with the formation of exofunctionalized tetracyclic quinoid systems was studied. Different numbers of products were isolated by liquid chromatography for different hydrazides. The products were identified as atropisomers. Generally, only one isomer was isolated for N'-(4,6-dimethylpyrimidin-2-yl)benzohydrazide, while two and three isomers were isolated for N'-(6-chloropyridazin-3-yl) benzohydrazide and for N'-(4-chlorophthalazin-1-yl) benzohydrazide, respectively. To determine their structure, modeling of the geometries and NMR spectra by DFT methods was performed. The structure of the obtained isomers was established based on 1H, 13C NMR and NOESY spectra, the results well agree with the simulation results.

scholarly journals Synthesis and HPLC Enantioseparation of Derivatives of the 3-hydroxyphenylethanone

2012 ◽  
Vol 59 (2) ◽  
pp. 15-27
Author(s):  
R. Čižmáriková ◽  
A. Némethy ◽  
J. Valentová ◽  
K. Hroboňová ◽  
K. Bruchatá
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
1H Nmr ◽  
13C Nmr ◽  
High Performance ◽  
Nmr Spectra ◽  
Stationary Phases ◽  
13C Nmr Spectra ◽  
Basic Part ◽  
Derivatives Of

AbstractWithin the framework of the study of the synthesis and high-performance liquid chromatography (HPLC) enantioseparation the series of 9 derivatives of 3-hydroxyphenylethanone was prepared by a well-tried method. The structure of the prepared compounds was confirmed on the basis of interpretation of the IR, UV, 1H NMR and 13C NMR spectra. An enantioseparation of prepared compounds was performed using HPLC on a native teicoplanin (Chirobiotic T) and the amylose tris (3,5-dimethylphenylcarbamate) (Chiralpak AD) chiral stationary phases, which is more suitable for the enantioseparation of all prepared compounds especially with heterocycles in the basic part of a molecule.

scholarly journals Synthesis of new compounds of the aryloxyaminopropanol type and their HPLC enantioseparation

2013 ◽  
Vol 60 (2) ◽  
pp. 37-42
Author(s):  
Čižmáriková R. ◽  
Némethy A. ◽  
Valentová J. ◽  
Hroboňová K. ◽  
Adamcová K.
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
1H Nmr ◽  
13C Nmr ◽  
High Performance ◽  
Nmr Spectra ◽  
13C Nmr Spectra ◽  
Thinlayer Chromatography ◽  
New Compounds

Abstract This article describes a preparation of some new compounds of the aryloxyaminopropanol type derived from 4-hydroxyphenylpropan- 1-one with phenylamino, cyclohexylamino and isobutylamino group in the hydrophilic part and methoxymethyl or ethoxymethyl substituent in the lipophilic part of the molecule. The purity of the prepared compounds was checked by thinlayer chromatography and the structure was confirmed on the basis of interpretation of the IR, UV, 1H NMR and 13C NMR spectra. An enantioseparation of the prepared compounds was performed by using high-performance liquid chromatography on an amylase tris(3,5-dimethylphenylcarbamate) (Chiralpak AD) and native teicoplanin (Chirobiotic T). The chromatographic results such as retention, separation and resolution factors have shown that Chiralpak AD is more suitable for enantioseparation of some of the prepared compounds.

Some Considerations Regarding the 1H and 13C Spectra of 4-(1-azulenyl)-2,6-bis(2-heteroaryl-vinyl)- pyrylium and Pyridinium and their Corresponding Pyridines

2018 ◽  
Vol 69 (1) ◽  
pp. 64-69
Author(s):  
Liviu Birzan ◽  
Mihaela Cristea ◽  
Constantin C. Draghici ◽  
Alexandru C. Razus
Keyword(s):  
Double Bond ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Pyridinium Salts ◽  
13C Nmr Spectra ◽  
1H And 13C Nmr ◽  
Pyrylium Salts

The 1H and 13C NMR spectra of several 2,6-diheteroarylvinyl heterocycles containing 4-azulenyl moiety were recorded and their proton and carbon chemical shifts were compared with those of the compounds without double bond between the heterocycles. The influence of the nature of central and side heterocycles, molecule polarization and anisotropic effects were revealed. The highest chemical shifts were recorded for the pyrylium salts and the lowest at pyridines, but in the case of the pyridinium salts, the protons chemical shifts at the central heterocycle are more shielded due to a peculiar anisotropy of the attached vinyl groups.

The Electron Effect of Aromatic Group: Control Conformation of 2-Aromatic Cyclododecanone Derivatives

2020 ◽  
Vol 24 (10) ◽  
pp. 1139-1147
Author(s):  
Yang Mingyan ◽  
Wang Daoquan ◽  
Wang Mingan
Keyword(s):  
1H Nmr ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
The Other ◽  
Repulsive Interaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Effect ◽  
Group Control

2-Phenylcyclododecanone and 2-cyclohexylcyclododecanone derivatives were synthesized and characterized by 1H NMR, 13C NMR, HR-ESI-MS and X-ray diffraction. Their preferred conformations were analyzed by the coupling constants in the 1H NMR spectra and X-ray diffraction, which showed the skeleton ring of these derivatives containing [3333]-2-one conformation, and the phenyl groups were located at the side-exo position of [3333]-2-one conformation due to the strong π-π repulsive interaction between the π- electron of benzene ring and π-electron of carbonyl group. The cyclohexyl groups were located at the corner-syn or the side-exo position of [3333]-2-one conformation depending on the hindrance of the other substituted groups. The π-π electron effect played a crucial role in efficiently controlling the preferred conformation of 2-aromatic cyclododecanone and the other 2-aromatic macrocyclic derivatives with the similar preferred square and rectangular conformations.

13C-NMR spectra of substituted thiophenecarboxylic acids

1977 ◽  
Vol 42 (7) ◽  
pp. 2167-2170 ◽  
Author(s):  
I. Stibor ◽  
L. Radics ◽  
M. Janda ◽  
J. Šrogl ◽  
M. Němec
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
13C Nmr Spectra

13C NMR spectra of 1-aryl-ferrocenylethylenes

1986 ◽  
Vol 51 (3) ◽  
pp. 670-676 ◽  
Author(s):  
Eva Solčániová ◽  
Štefan Toma ◽  
Tibor Liptaj
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
Substituent Effects ◽  
13C Nmr Spectra ◽  
Bridge Group ◽  
C Nmr ◽  
Electron Effects

13C NMR spectra of 18 ferrocene analogues of trans stilbenes (1-aryl-2-ferrocenylethylenes) were measured. It was found that bridge group weakens the transfer of the substituent electron effects into ferrocene nucleus, especially distinctly into 3',4'positions of cyclopentadienyl ring. The transfer of substituent effects into β-position of the bridge -CH=CH- is greater in derivatives studied by us than in stilbenes. Synthesis of 1-(4-dimethylaminophenyl)-2-ferrocenylethylene is described.

17O and 13C NMR spectra of some geminal diacetates

1988 ◽  
Vol 53 (3) ◽  
pp. 588-592 ◽  
Author(s):  
Antonín Lyčka ◽  
Josef Jirman ◽  
Jaroslav Holeček
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
The Other ◽  
13C Nmr Spectra ◽  
Other Hand ◽  
Carboxylic Esters ◽  
C Nmr ◽  
Oxygen Atoms

The 17O and 13C NMR spectra of eight geminal diacetates RCH(O(CO)CH3)2 derived from simple aldehydes have been measured. In contrast to the dicarboxylates R1R2E(O(CO)R3)2, where E = Si, Ge, or Sn, whose 17O NMR spectra only contain a single signal, and, on the other hand, in accordance with organic carboxylic esters, the 17O NMR spectra of the compound group studied always exhibit two well-resolved signals with the chemical shifts δ(17O) in the regions of 183-219 ppm and 369-381 ppm for the oxygen atoms in the groups C-O and C=O, respectively.

Proximity and conformation effects in 29Si and 13C NMR spectra of di-ortho substituted trimethylsiloxybenzenes

1990 ◽  
Vol 55 (8) ◽  
pp. 2027-2032 ◽  
Author(s):  
Jan Schraml ◽  
Robert Brežný ◽  
Jan Čermák
Keyword(s):  
Benzene Ring ◽  
13C Nmr ◽  
Proximity Effect ◽  
Nmr Spectra ◽  
Methoxy Group ◽  
Chemical Shifts ◽  
Proximity Effects ◽  
13C Nmr Spectra ◽  
Methoxy Groups ◽  
C Nmr

29Si and 13C NMR spectra of five 4-substituted 2,6-dimethoxytrimethylsiloxybenzenes were studied with the aim to elucidate the nature of the deshielding proximity effects observed in the spectra of ortho substituted trimethylsiloxybenzenes. The sensitivity of 29Si chemical shifts to para substitution is in the studied compounds essentially the same as in mono ortho methoxytrimethylsiloxybenzenes. The deshielding proximity effect of the ìsecondî methoxy group is somewhat smaller than that of the ìfirstî group. The present results indicate that the two methoxy groups assume coplanar conformations with the benzene ring and are turned away from the trimethylsiloxy group which is not in the benzene plane. It is argued that in mono ortho methoxytrimethylsiloxybenzenes the two substituent groups adopt the same conformations as in the compounds studied here.

Sign in / Sign up

Export Citation Format

Share Document