3337-17-5Relevant articles and documents
Fowler
, p. 1321 (1972)
Electrochemistry of aqueous pyridinium: Exploration of a key aspect of electrocatalytic reduction of CO2 to methanol
Yan, Yong,Zeitler, Elizabeth L.,Gu, Jing,Hu, Yuan,Bocarsly, Andrew B.
, p. 14020 - 14023 (2013)
The mechanism by which pyridinium (pyrH+) is reduced at a Pt electrode is a matter of recent controversy. The quasireversible cyclic voltammetric wave observed at -0.58 V vs SCE at a Pt electrode was originally proposed to correspond to reduction of pyrH+ to pyridinyl radical (pyrH?). This mechanistic explanation for the observed electrochemistry seems unlikely in light of recent quantum mechanical calculations that predict a very negative reduction potential (-1.37 V vs SCE) for the formation of pyrH?. Several other mechanisms have been proposed to account for the discrepancy in calculated and observed reduction potentials, including surface adsorption of pyrH?, reduction of pyrH+ by two electrons rather than one, and reduction of the pyrH+ proton to a surface hydride rather than a π-based radical product. This final mechanism, which can be described as inner-sphere reduction of pyrH+ to form a surface hydride, is consistent with experimental observations.
de Koning et al.
, p. 2547 (1977)
Chemo- and regioselective catalytic reduction of N-heterocycles by silane
Lee, Sun-Hwa,Gutsulyak, Dmitry V.,Nikonov, Georgii I.
supporting information, p. 4457 - 4464 (2013/09/23)
The ruthenium complex [Cp(iPr3P)Ru(NCCH3) 2]+ (1) catalyzes the regioselective hydrosilylation of pyridines to 1,4-dihydropyridines. Substitution in the 3- and 5-positions is tolerated, whereas pyridines with substituents in the 2-, 4-, and 6-positions are not reduced. Reduction of functionalized pyridines having keto and ester substituents results in a mixture of products. N-Silyl-1,4-dihydropyridine reacts with ketones and aldehydes to give products of N-Si addition across the C=O bond. Hydrosilylation of pyridine in acetone results quantitatively in the addition product PhMe2SiO-CMe2-NC5H 6, which decomposes in hexane to give the parent dihydropyridine HNC5H6. The phenanthroline complex [Cp(phen)Ru(NCCH 3)2]+ (10) catalyzes regioselective 1,4-reduction of phenanthroline by a 3-4-fold excess of silane/water or silane/alcohol mixtures. The Cp* analogue [Cp*(ph n)Ru(NCCH 3)2]+ (9) catalyzes 1,4-regioselective monohydrosilylation of phenanthroline, quinoline, acridine, and 1,3,5-triazine and the 1,2-reduction of isoquinoline. In contrast, 2-substituted phenanthroline, pyrazine, 2-ethylpyridine, 2,6-lutidine, 2,4-lutidine, and pyrimidine are not reduced under these conditions by either of the catalysts studied.
Trisubstituted heterocyclic compounds and their use as fungicides
-
, (2008/06/13)
Compounds of general formula (I): in which:Het represents a five or six membered saturated, partially unsaturated or aromatic ring containing between one and six heteroatoms of the group N, O, S, in which the heterocycle is substituted in an adjacent manner with -P-Q1-T-Q2, -GZ and Y, such that the substituant -GZ is adjacent to both. the other substituants being as defined in the description,process for preparing these compounds,fungicidal compositions comprising these compounds,processes for treating plants by applying these compounds or compositions.
