Oxidative coupling of 1-alkyl(benzyl)-4-(gamma-Pyridyl)-1,2,5,6-tetrahydropyridines with acetone in the presence of KMnO4 follows two pathways and yields both 1-R-2-(acetylmethylene)tetrahydropyridines and 1-R-3,4-dihydroxypiperidin-2-ones. When acetonitrile is used instead of acetone, the reaction under similar conditions occurs as selective ketodihydroxylation of the starting piperideines yielding 1-R-3,4-dihydroxy-4(gamma-Pyridyl)piperidin-2-ones . The molecular and crystal structures of one of these products (R = Et) was studied by X-ray diffraction analysis.
A Series of Polyoxometalate‐Viologen Photochromic Materials for UV Probing, Amine Detecting and Inkless and Erasable Printing
作者:Jun Ying、Liang Jin、Chen‐Xi Sun、Ai‐Xiang Tian、Xiu‐Li Wang
DOI:10.1002/chem.202103268
日期:2022.1.10
Compounds were designed and constructed by using two viologen ligands. Compounds 1–3 show excellent photochromic features with fast photoresponse under irradiation of ultraviolet light with different degrees of color changes. These Compounds exhibit aminedetecting and inkless and erasableprinting properties, and they can be prepared into a mixed matrix film as a good UV detector.
Electronic Structure and Electrooptical Properties of Radicals Formed upon Reduction of N-Alkyl 4,4′-Bipyridylium Salts
作者:V. V. Minin、M. I. Zakirov、N. N. Efimov、P. V. Mel’nikov、E. L. Nodova、B. I. Shapiro、V. M. Novotortsev
DOI:10.1134/s0036023618060189
日期:2018.6
N-Alkyl 4,4'-bipyridylium salts were synthesized and characterized. Cyclic voltammetry investigation showed that monosubstited 4,4'-bipyridylium salts are prone to reversible single-electron reduction. The formal redox potentials vs. a saturated silver chloride electrode were determined for different potential sweep rates. High-resolution ESR spectra of the radical cations formed upon the reduction of N-substituted 4,4'- bipyridylium salts in acid media were measured and interpreted. The substituent structure and the type of anion in the molecule have a considerable effect on the spin density distribution, current-voltage characteristics, and elctrooptical properties. The applicability of monosubstituted 4,4'-bipyridylium salts as photoelectrochromic compounds was studied.