NMR Studies of 2-Aryl Derivatives of Benzimidazole, Benzimidazolium Ion, and Benzimidazoline
摘要:
A series of 2-arylbenzimidazoles, 2-aryl-1,3-dimethylbenzimidazolium iodides, and 2-aryl-1,3-dimethylbenzimidazolines were prepared and their NMR spectra were examined. The substituent parameters were calculated for 2-benzimidazolyl, 2-benzimidazoliumyl, and 2-benzimidazolinyl groups on the chemical shifts of the protons and the carbons of benzene ring. The 2-benzimidazoliumyl group was found to cause a significant up-field shift of the ipso-carbon signal and down-field shift for the ortho- and para-carbon signals. On the other hand, the 2-benzimidazolyl and the 2-benzimidazolinyl groups cause down-field shift of the ipso-carbon signals but cause almost negligible change on the other carbon signals.
Marcus Theory of a Parallel Effect on α for Hydride Transfer Reaction between NAD<sup>+</sup> Analogues
作者:In-Sook Han Lee、Eun Hee Jeoung、Maurice M. Kreevoy
DOI:10.1021/ja963768l
日期:1997.3.1
Rate and equilibrium constants for hydridetransfer from a series of 1,3-dimethyl-2-substituted phenylbenzimidazolines to a pyridinium ion, a quinolinium ion, and a phenanthridinium ion have been evaluated. Each oxidizing agent gives a linear Bronsted plot with slope, α. The α values vary systematically with the spontaniety of the reactions. They are in reasonable agreement with the predictions of