Excellent correlation between substituent constants and pyridinium N-methyl chemical shifts
作者:Sha Huang、Jesse C.S. Wong、Adam K.C. Leung、Yee Man Chan、Lili Wong、Myrien R. Fernendez、Amanda K. Miller、Weiming Wu
DOI:10.1016/j.tetlet.2009.06.081
日期:2009.9
Substituents on the pyridinium ring of N-methylpyridinium derivatives, especially those on the 2- or 4-position, have a large effect on the 1H and 13C NMR chemical shifts of the N-methyl group. Reasonable correlations between the chemical shift changes and the resonance substituentconstants are observed. The dual substituent parameter approach provides an excellent correlation when a combination of
Photosolvolysis reactions of 3-alkoxypyridinium tetrafluoroborate salts
作者:Clive S. Penkett、Iain D. Simpson
DOI:10.1016/s0040-4020(99)00263-x
日期:1999.5
of a series of 3-alkoxypyridinium tetrafluoroborate salts in alcohol solution resulted in the formation of cyclopentenone ketals by diastereoselective incorporation of the alcohol solvent under the basic conditions of the photolysis reaction. In a second series of photochemical reactions, the same 3-alkoxypyridinium salts were irradiated in water to yield β-hydroxycyclopentanones stereoselectively
作者:Lihua Luo、Juan Tang、Rui Sun、Wenjing Li、Xueli Zheng、Maoling Yuan、Ruixiang Li、Hua Chen、Haiyan Fu
DOI:10.1021/acs.orglett.2c00725
日期:2022.4.22
A direct pyridinium C–H sulfonylimination has been developed for the synthesis of sulfonyl iminopyridine derivatives with high efficiency. This transformation features the direct and efficient formation of a C═N bond with a high functional group tolerance under metal-free conditions. The spectroscopic properties potentially enable these sulfonyl iminopyridine compounds to be useful new emitting materials
Copper-Mediated and Palladium-Catalyzed Cross-Coupling of Indoles and <i>N</i>-Methylpyridinium Salts: A Practical Way to Prepare 3-(Pyridin-2-yl)indoles
the corresponding 3-(pyridin-2-yl)indoles in moderate to good yields, wherein related electron-rich heterocycles (e.g., indole, 1-methylpyrrole, benzofuran, benzo[b]thiophene) are also applicable. Streamlined operation, good functional group tolerance, and late-stage modifications make this twofold C–H activation protocol an attractive route for the synthesis of 3-(pyridin-2-yl)indole derivatives.