Studies on the Linear Free Energy Relationship in Methyl Cinnamates by 1H-NMR Spectrometry

[摘要] Chemical shift values of �?-proton of trans- and cis-methyl cinnamates are well correlated with �? (ヲI, ヲRo), and (F, R) (r = 0.999 - 0.879). It is observed that (1) the degree of variation of ヤH�? value by varying the substituents in trans-cinnamates is similar to that of cis-cinnamates (ヱtrans = 0.296, ヱcis = 0.284), (2) resonance contribution is larger in the trans-cinnamates than that in the cis-cinnamates, but inductive contribution is reversed, (3) for m-substituted derivatives, resonance contribution is very small compared to that for p-substituted derivatives.

[学科分类] 化学（综合）