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用AB INITIO法对只含酚羟基的 7种酚化合物的苯环碳原子 (Ci)的净电荷 (Qi)做了计算 ,并测定或查阅了它们的13CNMR谱 ,参考标准图谱找出了Ci 对应的化学位移δi,发现Qi δi间呈现较好的线性关系 .每种化合物均有最负净电荷 (Qmin)与最低化学位移 (δmin) ,Qmin与δmin出现在酚羟基邻位同一碳原子上 ,而这一碳原子具有最大的亲核亲电反应活性 .那些δi>130的碳原子反应活性极小 ,以至不能发生亲核亲电反应 .在酸、碱条件下会改变酚化合物的电荷分布和化学位移 ,因而其反应活性也随之改变 .
The net charge (Qi) of the benzene ring carbon atoms (Ci) of seven phenolic compounds containing only phenolic hydroxyl groups was calculated by the AB INITIO method and their 13CNMR spectra were measured or reviewed. The Ci spectra were found with reference to the standard spectra The chemical shifts δi show that there is a good linear relationship between Qi δi.Each compound has the lowest negative charge (Qmin) and the lowest chemical shift (δmin), and Qmin and δmin appear on the same carbon atom of ortho-phenolic hydroxyl group, And this carbon atom has the largest nucleophilic electrophilic reactivity. Those carbon atoms with δi> 130 are so small that they can not undergo nucleophilic electrophilic reactions that alter the charge distribution of the phenolic compounds under acid and base conditions and The chemical shift, therefore, its reactivity also changes.