22739-24-8Relevant articles and documents
Cationic motions and crystal structures of 1,3,5-trimethylpyridinium hexachlorometallates [(CH3)2C5H3N(CH3)]2MCl6 (M is SN and Te) studied by 1H NMR and X-ray diffraction
Sato, Setsuko,Ishida, Hiroyuki,Nagae, Makoto,Kashino, Setsuo,Furukawa, Yoshihiro,Weiss, Alarich
, p. 39 - 46 (1998)
The crystal structure of 1,3,5-trimethylpyridinium hexachlorometallates [(CH3)2C5H3N(CH3)]2MCl6 (M is Sn and Te) were determined at 298 K and found to be orthorhombic Pnnm (No. 58) and Z = 2, a = 8.996(2), b = 11.330(2), c = I 1.596(2) A, V = 1182.0(7) A3 for the stannate, and a = 9.072(4), b = 11.399(5), c = 11.63(2) A, V = 1203(3) A3 for the tellurate, by single-crystal X-ray diffraction. No phase transition was detected by DTA from 80 to 573 K. The cationic motions were studied by 1H NMR and the C3 reorientation of the CH3 groups was observed below 273 K, having an activation energy of 3.1 kJ mol-1 for the stannate and 3.7 kJ mol-1 for the tellurate. Another cationic motion, with an activation energy of about 20 kJ mol-1, was observed above 380 K for both salts. This is attributable to the pseudo-C3 reorientation around the axis perpendicular to the pyridinium ring. The cationic motions and the crystal structure are discussed from the point of view of the hydrogen bonding.
Synthesis of pyridine acrylates and acrylamides and their corresponding pyridinium ions as versatile cross-linkers for tunable hydrogels
Mateescu, Markus,Nuss, Isabell,Southan, Alexander,Messenger, Hayley,Wegner, Seraphine V.,Kupka, Julia,Bach, Monika,Tovar, Guenter E. M.,Boehm, Heike,Laschat, Sabine
supporting information, p. 1243 - 1253 (2014/05/06)
A small library of cross-linkers for hydrogels was synthesized. The cross-linkers consisted of 2,6- and 3,5-diacylpyridine or 2,4,6-triacylpyridine as the core unit, which were tethered via ethylene glycol, amino ethanol, and 1,n-diamine spacers to terminal acrylate or acrylamide moieties. Esterification and amide formation of the terminal acryl units were found to be dependent on the ratio of NH/O in the spacer, the constitution pattern of the pyridine ring, and the total number of acryl groups. Thus, esters generally gave higher yields than amides decreasing with increasing number of NH in the spacer and with increasing number of acryl units. In the case of 3,5-diacylpyridine derivatives, these trends were less prominent as compared to the 2,6-diacylpyridine series, indicating that steric hindrance and unfavorable hydrogen bonding interaction of the spacers might influence the observed reactivity differences. The 3,5-diacylpyridines were converted to the N-methylpyridinium salts and selected members of both neutral and cationic 3,5-diacylpyridinium derivatives were submitted to hydrogelations with synthetic polymer poly(1-glycidylpiperazine) via aza-Michael addition and thiolated natural hyaluronan via thio-Michael reaction, respectively. Rheological properties of the resulting hydrogels were studied, revealing that both spacer type as well as charge affected elastic moduli and degree of swelling. Georg Thieme Verlag Stuttgart New York.
Deuterium Kinetic Isotope Effects in Quaternization of Polymethylpyridines (CH3 or CD3) with Methyl Iodide or (2H3) Methyl Iodide.
Balaban, Alexandru T.,Bota, Anisia,Oniciu, Daniela C.,Klatte, Gerd,Roussel, Christian,Metzger, Jacques
, p. 559 - 583 (2007/10/02)
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