三岔共轭体系中的结构效应(Ⅵ)——氮杂查耳酮类化合物红外光谱中的同系线性规律

THE STRUCTURAL EFFECT IN FORKED CONJUGATIVE SYSTEMS(Ⅵ)——THE RULE OF HOMOLOGOUS LINEARITY FOR I.R.SPECTRA OF AZACHALCONE COMPOUNDS

本文合成并研究了_(2)P0nB、_(4)P0nB、_(2)Q0nB等11个三岔共轭化合物的红外光谱。实验表明这些化合物的基因特征吸收波数近似地遵守同系线性规律,相关系数r为0.982-1.000,与相应线性体系的同系直线比较,它们的斜率较小。这表明一个分岔的引入导致基因特征吸收波长红移,并表明在三岔体系中是分子整体性占优势而分岔基团的特性是受到分子整体性制约的。

For a study on the forked conjugative system and its relation with the corresponding linear conjugative series,in this paper three type with 11 compounds of forked conjugative azachalcone homlogs.(2P0nB,4P0nB,2QonB)have been synthesized,of which the starred ones are new compounds.2PonB■(n=1^*,2^*,3^*,4^*.)4PonB■(N=1^*,2^*,3^*,4^*.)2QonB■(n=1,2,3^*)The I.R.specrra of these compounds have been determined.The experimental results show that some particular group absorption wave numbers(e·g·carbonyl,ethyl)conform well to the rule of homologous linearity,with correlation cofficients ranging from 0.982 to 1.000.The reason for this is probably that the molecular vibration energies of the homologous compounds also conform approximately to the rule of homologous linearity.when the homologous lines for the group’s characteristic absoption wave numbers of the forked systems are compared with those of the corresponding linear homologs,it has been found that the former locate lower than the latter,and with a smaller slope.this shows that the introduction of an electron-attractive pyridyl or quinolyl as a branching group causes a red shift in the charecteristic absoption wave length.This fact lends support to the conclusion that the moleclar integrity is the main trend in the forked systems,and the forking group’s effect is under the restraint of it.