Results 151 to 160 of about 14,921 (209)

The synthetic potential of pyridinium salt photochemistry

Photochemical & Photobiological Sciences, 2008
The discovery in the 1970s by Kaplan, Wilzbach and Pavlik that pyridinium salts undergo a unique cyclization reaction to produce bicyclic-aziridines was virtually unrecognized for nearly three decades. It was only comparatively recently that the process was explored in more detail and its synthetic potential exploited.
Jiwen, Zou, Patrick S, Mariano
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Infrared spectra of pyridinium salts in solution—III. Associations of pyridinium salts with bases

Spectrochimica Acta Part A: Molecular Spectroscopy, 1983
Associations of pyridinium salts X-Py+HA− (A− = SbCl−6, ClO−4, BF−4, I−, Br− and Cl−) with a wide series of aprotic bases and with protic solvents (water and fluoroalcohols) have been studied by infrared spectroscopic methods. Constants of association Ka of the pyridinium salts with the bases at different temperatures have been measured and enthalpy ...
S.E. Odinokov, A.A. Mashkovsky, A.A. Nabiullin   +2 more
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Thiazolopyridinium salts. Part II. Approaches to thiazolo[3,4-a]-pyridinium salts and isothiazolo[2,3-a]pyridinium salts

Journal of the Chemical Society C: Organic, 1969
Attempts to synthesise thiazolo[3,4-a]pyridinium salts (3) and isothiazolo[2,3-a]pyridinium salts (2) by dehydration with boiling acetic anhydride of the 5,6,7,8-tetrahydro-8-oxothiazolo[3,4-a]pyridinium salts (11) and (12) and of the 4,5,6,7-tetrahydro-4-oxoisothiazolo[2,3-a]pyridinium salt (6) respectively are reported. The reasons for the failure of
D. G. Jones, Gurnos Jones
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Isolable Pyridinium Trifluoromethoxide Salt for Nucleophilic Trifluoromethoxylation

Organic Letters, 2021
An isolable pyridinium trifluoromethoxide salt is prepared from the reaction of 4-dimethylaminopyridine with the commercially available liquid 2,4-dinitro(trifluoromethoxy)benzene. The salt is an effective trifluoromethoxide source for SN2 reactions to form trifluoromethyl ethers.
Geraldo Duran-Camacho, Devin M. Ferguson, Jeff W. Kampf, Douglas C. Bland, Melanie S. Sanford   +4 more
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Antimycobacterial Activity of Quaternary Pyridinium Salts and Pyridinium N-oxides - Review

Current Pharmaceutical Design, 2012
The treatment of tuberculosis and other mycobacterioses is still a major world health problem and new antimycobacterial compounds unrelated to approved drugs are in demand. Quaternary ammonium salts have revealed many usable properties especially as antimicrobials; they are widely used as disinfection and antiseptic agents.
Martin, Krátký, Jarmila, Vinšová
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Imidazo [1,2‐a] pyridinium salts

Journal of Heterocyclic Chemistry, 1965
Abstract2‐Alkylamino‐ or arylaminopyridines react directly with α‐bromoketones to afford 1‐alkyl‐ or 1‐arylimidazo[1,2‐a]pyridinium salts with substituents at position 2. Use of chloroacetaldoxime as the quaternizing agent yields (after hydrolysis) the imidazo‐[1,2‐a]pyridinium ion with no substituent at position 2.
C. K. Bradsher, E. F. Litzinger, M. F. Zinn   +2 more
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Pyridinium salts

Chemistry of Heterocyclic Compounds, 1974
P. P. Zarin', �. S. Lavrinovich, A. K. Aren   +2 more
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Dimerization of pyridinium salts by cyanide

Journal of the Chemical Society D: Chemical Communications, 1970
1,1′-Dihydro-4,4′-bipyridyls (II) are formed from certain pyridinium or 2-methylpyridinium salts and sodium cyanide.
Lawrence J. Winters, Nelson G. Smith, Martin I. Cohen   +2 more
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Catalytic hydrogenation of pyridinium salts

Chemistry of Heterocyclic Compounds, 1994
Catalytic hydrogenation of polysubstituted pyridinium salts leads to piperidines and their condensed analogs The spatial properties and conformational properties of the saturated azaheterocycles have been determined by13C NMR spectorscopy. It was shown that hydrogenation of the pyridinium salts occurs stereoselectively to form cis isomers in most cases.
P. V. Reshetov, S. A. Rozhnova, A. P. Kriven'ko   +2 more
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