N-烷氧基杂环在光化学电子转移反应中可以作为强大的单电子受体。这些物质的单电子还原导致形成自由基,该自由基经历 NO 键断裂以形成烷氧基自由基和中性杂环。已经确定了一系列具有不同取代基和离域程度的自由基的 NO 键断裂反应的动力学。获得了超过 7 个数量级变化的速率常数。描述了涉及避免锥形相交的反应势能表面。根据重要分子轨道的能量与反应势能面之间的关系,给出了反应速率常数随自由基结构变化的分子基础。
PyridineN‐oxide–BF2CF3 and –BF2C2F5 complexes and their derivatives were synthesized. Most of the complexes show fluorescence both in solution and in the solid state. By expanding the π‐conjugated skeleton, the color of the fluorescence could be changed dramatically. A fluorophore with a high solvent dependency could also be produced. Since such compounds can be synthesized on a gram scale in high
Einfache Synthesen von 1,2-Diaryl- und Triarylethenen mit trägergebundenen Fluoridbasen
作者:D. Hellwinkel、K. Göke、R. Karle
DOI:10.1055/s-1994-25617
日期:——
Facile Syntheses of 1,2-Diaryl- and Triarylethenes with Supported Fluoride Bases Differently substituted arenecarbaldehydes, mainly benzaldehydes, can be very efficiently condensed with a wide variety of methylbenzenes having an electron-withdrawing group in the para-position, as well as with fluorenes, xanthene, cyclopentadienes and indenes by using a standardized KF- or CsF-Al2O3 base system in dimethylformamide.
Studies on tertiary amine oxides. LXXXII. The reaction of 1-oxido-4(or 2)-pyridinediazonium tetrafluoroborate with olefins in the presence of palladium complex.
1-Oxido-4-pyridinediazonium tetrafluoroborate (4-PFB) reacts with olefins (cyclopentene, styrene, ethyl acrylate, indene, cyclohexene, cyclooctene, 1-octene and 1-dodecene) in the presence of tris(dibenzylideneacetone)dipalladium to afford the corresponding alkenylated products (1, 2, 3, 4, 5, 6, 7 and 8) in good yields.1, 2, 3, 5-Oxatriazolo[5, 4-α]pyridinium tetrafluoroborate (2-PFB) also reacts with cyclopentene and styrene to give 2-cyclopentenylpyridine 1-oxides (13 and 14) and (E)-2-(α-styryl)pyridine 1-oxide (15), respectively, in low yields.
Photoisomerization of Styryl Derivatives of Pyridine N-Oxide
作者:Yu. A. Gubarev、N. Sh. Lebedeva、E. S. Yurina、V. P. Andreev、A. I. V’yugin
DOI:10.1134/s0036024418040052
日期:2018.4
The trans–cis- and cis–trans-isomerization of styryl derivatives of heterocyclic N-oxides in acetonitrile and ethanol is studied. The isomerization quantum yields and spectral characteristics of the cis-form of the investigated N-oxides are determined. No thermally induced cis–trans-conversion is detected.
N-Oxide-to-Carbon Transmutations of Azaarene N-Oxides
作者:Nicholas A. Falcone、Sam He、John F. Hoskin、Sandeep Mangat、Erik J. Sorensen
DOI:10.1021/acs.orglett.4c01263
日期:2024.5.24
editing of molecular structures. Herein, we describe the expansion of an underdeveloped transformation that directly converts azaarene-derived N-oxides to all-carbon arenes. This ring transmutation exhibits good functional group tolerance and replaces the N-oxide moiety with either unsubstituted, substituted, or isotopically labeled carbon atoms in a single laboratory operation.