1004-16-6Relevant articles and documents
The influence of weak hydrogen bonds on the properties of 3-cyano-N-methylpyridinium chloride and iodide
Koplitz, Lynn Vogel,Bay, Kevin D.,DiGiovanni, Neil,Mague, Joel T.
, p. 391 - 402 (2003)
The iodide salt of 3-cyano-N-methylpyridinium cation crystallizes as yellow needles in the monoclinic space group P21/n with a = 4.8726(5), b = 12.9380(15), c = 13.4629(15) A, β = 97.463(2)°, and Z = 4 (mp 196°C). The chloride salt forms colorless plates in the monoclinic space group P21/m with a = 7.9488(8), b = 6.4023(7), c = 8.0844(8) A, β = 112.987(2)°, and Z = 2 (mp > 220°C). For ring hydrogens interacting with the anion, each salt has C-H ... X distances and angles consistent with weak hydrogen bonds as described by recently published criteria (Brammer et al. Cryst. Growth Design 2001, 1, 277; Steiner Acta Crystallogr., Sect B 1998, 54, 456; Crystallogr. Rev. 1996, 6, 1). The chloride salt has an additional interaction between H5 and the cyano nitrogen on an adjacent cation in the same layer, or a total of four coplanar hydrogen bonds per cation. It forms sheets which stack along the b axis. The iodide has fewer hydrogen bonds from the ring and the cations are tilted relative to each other. There is an unusual hydrogen bond from a methyl hydrogen to a cyano nitrogen in the iodide. Roughly oval (3.8 x 5.7 A) open channels bounded by H5 and iodides run along the a axis. Stabilization of these solids by hydrogen bonding is estimated to be at least 1.9 kcal/mole more for the chloride than for the iodide.
Shape-Selective Assemblies of Charge-Transfer Complexes as Molecular Probes for Water Adsorption in Zeolites
Yoon, K. B.,Huh, T. J.,Kochi, J. K.
, p. 7042 - 7053 (1995)
The supercage of zeolite-Y and the restricted channels of zeolite-L, mordenite, and mazzite act as shape-selective hosts to a series of brightly colored charge-transfer complexes +, D> assembled in situ by the intercalation of various aromatic donors (D) into the ion-exchanged (colorless) zeolites with different pyridinium acceptors (A+).Upon the deliberate introduction of water (vapor) into the variously colored zeolites, the diffuse reflectance spectra suffer pronounced spectral shifts of the charge-transfer bands, the magnitude of ΔhνCT being uniquely dependent on the molecular size/shape of A+ and D, as well as the dimensions of the zeolite cavities.In accordance with the bond compression model of intermolecular charge-transfer complexes, the bathochromic shifts to lower energies (+ΔhνCT) are ascribed to hyperbaric effects induced by the absorption of water within the constricted channels of zeolite-L, mordenite, and mazzite (but not in the larger supercage of zeolite-Y).The importance of water coordination is also underscored by the unusual hypsochromic effects (-ΔhνCT) that are observed when cyano-substituted pyridinium acceptors o-CP+ and p-CP+ are doped into zeolite-Y (but not into zeolite-L, mordenite, or mazzite).These results thus show that the intermolecular charge-transfer complexes +, D> are shape-selective and can be used as quantitative visual probes for water absorption into zeolite cavities, and they provide the experimental basis for further theoretical analysis.
Excellent correlation between substituent constants and pyridinium N-methyl chemical shifts
Huang, Sha,Wong, Jesse C.S.,Leung, Adam K.C.,Chan, Yee Man,Wong, Lili,Fernendez, Myrien R.,Miller, Amanda K.,Wu, Weiming
, p. 5018 - 5020 (2009)
Substituents on the pyridinium ring of N-methylpyridinium derivatives, especially those on the 2- or 4-position, have a large effect on the 1H and 13C NMR chemical shifts of the N-methyl group. Reasonable correlations between the chemical shift changes and the resonance substituent constants are observed. The dual substituent parameter approach provides an excellent correlation when a combination of polar and resonance substituent constants is employed.
Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts
Kiamehr, Mostafa,Moghaddam, Firouz Matloubi,Mkrtchyan, Satenik,Semeniuchenko, Volodymyr,Supe, Linda,Villinger, Alexander,Langer, Peter,Laroshenko, Viktor O.
supporting information, p. 1119 - 1126 (2013/07/19)
The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.0 2,7]trideca-2(7),11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of t
Pyridinium salts - Versatile reagents for the regioselective synthesis of functionalized thiazocino[2,3-b]indoles by tandem dinucleophilic reactions of thiooxindoles
Kiamehr, Mostafa,Gormay, Pavel V.,Villinger, Alexander,Langer, Peter,Iaroshenko, Viktor O.,Moghaddam, Firouz Matloubi,Semeniuchenko, Volodymyr
supporting information, p. 9685 - 9693,9 (2020/08/20)
The reaction of thiooxindoles with various 2- and 3-substituted pyridinium salts afforded a variety of functionalized thiazocinoindoles. The products have been prepared in good to excellent yields by regioselective dinucleophilic C/S-cyclocondensation of
Quantitative in situ measurement of ion transport in polypyrrole/poly(styrenesulfonate) films using rotating ring-disk voltammetry
Salzer, Corey A.,Elliott, C. Michael,Hendrickson, Susan M.
, p. 3677 - 3683 (2007/10/03)
An approach based on rotating ring-disk electrode (RRDE) voltammetry is described for the quantitative, in situ measurement of ion transport between solution and conducting polymer films. The specific composite film studied in this report is polypyrrole/poly(styrenesulfonate) (pPy+/pSS-). Cation flux in and out of the polymer was obtained from the mass-transport-limited reduction current for the dopant cation(s) measured at the ring during redox cycling of the polymer. Crucial to this method is the use of a supporting electrolyte that is sterically inhibited from passing into the film and the use of dopant ions that adhere to specific electrochemical constraints. With this method it was possible to quantitatively account for all changes in charge compensation in the film by the specific cation(s) involved. Three different cations were explored alone and in paired combinations. Solutions containing mixtures of dopant cations were studied to determine whether the pPy+/pSS- films exhibit preferential doping. Kinetic factors, likely due to steric differences in the dopant cations, were found to lead to significant preferential doping of the polymer.
1,2,3-Triazole and tetrazole substituted piperidine or tetrahydropyridine compounds useful as acetylcholine agonists
-
, (2008/06/13)
The present invention relates to novel compounds of the following formula, where the dotted line designates an optional bond: STR1 wherein "het" designates a five membered heterocyclic ring which may include 1 or 2 double bonds and 1-4 heteroatoms selected from nitrogen, oxygen or sulphur, provided that "het" may not designate a 1,2,4- or 1,3,4-oxadiazole; R1 is selected from hydrogen, lower alkyl, optionally substituted with phenyl which may be substituted with halogen, lower alkyl, or lower alkoxy, or a group R6 --CO--NH--CH2 -- or R6 --O--CO--, wherein R6 is lower alkyl, branched or unbranched, or phenyl optionally substituted with halogen, trifluoromethyl, lower alkyl, hydroxy, lower alkoxy, or lower acyloxy; R2 and R3 are the same or different, each representing hydrogen, lower alkyl, cycloalkyl (3-6 C-atoms), lower alkenyl, lower alkadienyl, lower alkynyl, optionally substituted with hydroxy, halogen or phenyl, in which the phenyl group may be substituted with halogen, trifluoromethyl, lower alkyl, hydroxy or lower alkoxy; R2 and R3 may further, respectively, be selected from trifluoromethyl or phenyl optionally substituted with halogen, trifluoromethyl, lower alkyl, hydroxy, lower alkoxy or lower acyloxy, or R2 and R3 may, respectively, be a group OR7 or SR7 wherein R7 is defined as R2 or R3, and if "het" includes 2 or more carbon atoms, R4 and R5 are the same or different, and each is defined as R2 or R3, and if "het" includes only one carbon atom, there is only one substituent, R4, on the heterocyclic ring, and R4 is defined as R2 or R3, as well as individual stereo isomers and pharmaceutically acceptable acid addition salts thereof. The invention moreover relates to methods for the preparation of the compounds of formula I, to novel intermediates, to pharmaceutical compositions containing same and to methods for the treatment of disorders, caused by malfunction of the acetylcholine (AcCh) or muscarinic system, by administering a non-toxic effective amount of a compound of formula I.
Ring Opening and Transamination of Pyridinium Salts
Fadda, A. A.,Abdelrazek, F. M.,El-Habbal, M. M.
, p. 194 - 195 (2007/10/02)
N-Alkyl-3-cyanopyridinium iodides (Ia-c) undergo ring opening and recyclization when heated with aq. alkyl amine to give 2-alkylamino-3-formylpyridines (IIa-c) and 3-cyanopyridine (III).However, when compounds Ia-c are treated with alkyl amines in which t
Kinetics of Quaternization of trans-4-(p- or m-Substituted styryl)pyridines with Methyl Iodide
Ananthakrishnanadar, P.,Rajasekaran, K.
, p. 324 - 325 (2007/10/02)
Second order rate constants have been measured for the reaction of several trans-4-(p- or m-substituted styryl)pyridines with methyl iodide in nitrobenzene at 30 deg C, 35 deg C, and 40 deg C.Arrhenius parameters as well as enthalpies and entropies of act
COVALENT ADDUCTS FROM 1,3-DISUBSTITUTED PYRIDINIUM SALTS AND PIPERIDINE
Moracci, F. Micheletti,Rienzo, B. Di,Tortorella, S.,Liberatore, F.
, p. 785 - 789 (2007/10/02)
Covalent adducts 3a-f have been isolated from the reaction between piperidine and pyridinium salts 1a-f. 3a-f are stable both in the solid state and in apolar solvents, whereas their fast dissociation back to piperidine and pyridinium ions occurs in aqueous solution.The latter, in the alkaline environment produced by the amine, yields the correspondent pseudobases, which are key intermediates of the subsequent reactions.For instance, the pseudobases from 1a,b can undergo either a ring-opening reaction or a redox process with the corresponding pyridinium cations.
