ChemInform Abstract: Reactions of Azinium Cations. Part 7. 13C-NMR Spectra and Electronic Structure of Neutral σ-Adducts from 1,4-Diazinium Cations and the Methylate Anion.

AbstractSynthesis of N-and C-substituted derivatives of benzo[h][1,6]naphthyridine, bearing 2-hydroxyethyl group has been made by quaternization reaction and by condensation of corresponding methylbenzonaphthyridines with formaldehyde. For six derivatives of isomeric benzo[c][1,5]-, benzo[h][1,6]-, and benzo[f][1,7]naphthyridines the 13C NMR spectra are discussed.For ten compounds the geometry was optimized with the AM1 and, in one case also with the ab initio 6–31G method; their effective charge values have also been calculated.

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13C NMR spectra and electronic structure of alkenylalanes

Russian Chemical Bulletin ◽

10.1007/bf02495255 ◽

1997 ◽

Vol 46 (12) ◽

pp. 2082-2085 ◽

Cited By ~ 3

Author(s):

R. R. Muslukhov ◽

L. M. Khalilov ◽

I. R. Ramazanov ◽

A. Z. Sharipova ◽

A. G. Ibragimov ◽

...

Keyword(s):

Electronic Structure ◽

13C Nmr ◽

Nmr Spectra ◽

13C Nmr Spectra

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Reaction of pyrido[2,1-a]isoindole with 1,4-naphtoquinone and study of the product by spectroscopic methods

French-Ukrainian Journal of Chemistry ◽

10.17721/fujcv4i2p33-39 ◽

2016 ◽

Vol 4 (2) ◽

pp. 33-39 ◽

Cited By ~ 1

Author(s):

Tatyana Yegorova ◽

Bogdan Barnych ◽

Zoia Voitenko

Keyword(s):

Electronic Structure ◽

13C Nmr ◽

Spectral Methods ◽

Nmr Spectra ◽

Spectroscopic Methods ◽

Cyclic Form ◽

13C Nmr Spectra ◽

Rearrangement Product ◽

The Way

Key role of the electronic structure of condensed isoindols in the way of the rearrangement was shown. Influence of the dienophile manifests in the requirement of the cyclic form of the dienophile itself. In the reaction of pyrido[2,1-a]isoindole with naphtoquinone rearrangement product of the first type was obtained and its structure was proven by spectral methods. Spectral criteria for the rearranged adducts of the first type for the pyrido[2,1-a]isoindole in the 13C NMR spectra were established. Products of reactions with naphthoquinone, 4-fluoro-, 2,5-difluorophenylmaleimides were isolated and characterized: (2E)-2-[(1,4-dihydroxy-2-naphthyl)(2-pyridin-2-ylphenyl)methylene]-4-hydroxynaphthalen-1(2H)-one, (3E)-1-(4-fluorophenyl)-3-[[1-(4-fluorophenyl)-2,5-dioxopyrrolidin-3-yl](2-pyridin-2-ylphenyl)methylene]pyrrolidine-2,5-dione, (3E)-1-(2,4-difluorophenyl)-3-[[1-(2,4-fluorophenyl)-2,5-dioxopyrrolidin-3-yl](2-pyridin-2-ylphenyl)methylene]pyrrolidine-2,5-dione.

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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

Revista de Chimie ◽

10.37358/rc.18.1.6045 ◽

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.

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Ab Initio Calculations of Conformational Effects on 13C NMR Spectra of Amorphous Polymers

10.1007/978-3-642-60644-1 ◽

1997 ◽

Cited By ~ 5

Author(s):

R. Born ◽

H. W. Spiess

Keyword(s):

Ab Initio Calculations ◽

Ab Initio ◽

13C Nmr ◽

Nmr Spectra ◽

Amorphous Polymers ◽

13C Nmr Spectra ◽

Conformational Effects

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13C-NMR spectra of substituted thiophenecarboxylic acids

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19772167 ◽

1977 ◽

Vol 42 (7) ◽

pp. 2167-2170 ◽

Cited By ~ 2

Author(s):

I. Stibor ◽

L. Radics ◽

M. Janda ◽

J. Šrogl ◽

M. Němec

Keyword(s):

13C Nmr ◽

Nmr Spectra ◽

13C Nmr Spectra

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13C NMR spectra of 1-aryl-ferrocenylethylenes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860670 ◽

1986 ◽

Vol 51 (3) ◽

pp. 670-676 ◽

Cited By ~ 5

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.

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17O and 13C NMR spectra of some geminal diacetates

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19880588 ◽

1988 ◽

Vol 53 (3) ◽

pp. 588-592 ◽

Cited By ~ 10

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.

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

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902027 ◽

1990 ◽

Vol 55 (8) ◽

pp. 2027-2032 ◽

Cited By ~ 1

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.

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