Pyridyl N-oxide

S-2-PicoIyl A-Oxide Thioether RSCH2-2-pyridyl N-Oxide (Chart 7)... 

Pyridyl-N-oxide chloride, AD79 Pyrimidine, AC44... 

DIMETHYL-5H-PYRIDO(4,3-b)INDOL-3-AMINE MONOACETATE see AJR500 (3,3-DIMETHYL-l - (m-PYRIDYL-N-OXIDE))TRIAZENE see DT 200 N -(4,6-DIMETHYL-2-... 

In spite of some apparent resemblance between the pyridinio (14) and the trimethylammonio groups, the former is more powerful as an inductive withdrawing substituent but it displays a small +M effect (81CCC584). On the whole, its electron-accepting properties are more significant than those of N-protonated pyridyl (15) and pyridyl N-oxide (16) groups (cf. Table III). 

Jaeger and Bard using a spin trapping technique (with a-phenyl N-tert-butyl nitrone, PBN, and a-(4-pyridyl N-oxide) N-tert-butyl nitrone, 4-POBN, as spin traps), have detected hydroxyl, OH, and perhydroxyl, HO2, radicals during band-gap irradiation of aqueous suspensions of Ti02 and platinised Ti02 powders. Titanium dioxide employed was a pre-reduced anatase powder and the experiments were performed in... 

A route taking advantage of the electrophilicity of the pyridyl N-oxide functionahty was reported by Smith et al. [386]. The authors used a polyacrylate polymer, which was terminally chlorinated with SOCI2 and then reacted with 2-chloropyridine N-oxide. The very unstable support-linked chloropyridinium species was claimed to react with the enamine. After acidolysis of the imine and basic hydrolysis of the N-oxyester, 2(6-chloro-2-pyridyl)cyclohexanone was obtained. 

The latter benchmark reaction for the preparation of 84 was also used recently by Reggelin to study a completely different kind of chiral polymeric bases (Scheme 10.15). In their work, the authors used pyridyl N-oxide substituted helically chiral poly(methacrylate)s 82 prepared by helix sense selective anionic polymerization of... 

Roesky, H.W. Andruh. M. The interplay of coordinative, hydrogen bonding and n-n stacking interactions in sustaining supramolecular solid-state architectures. A study case of bis(4-pyridyl)-and bis(4-pyridyl-N-oxide) tectons. Coord. Chem. Rev. 2003. 236. 91. and references therein. 

Under similar conditions, perfluorinated aryl and pyridyl N-oxide-substituted indoles could also be selectively C2 arylated in good yields (53-65%). ... 

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