Electronic substituent effect on intramolecular CH/π interaction as evidenced by NOE experiments
Electronic substituent effect on intramolecular CH/π interaction as evidenced by NOE experiments
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NOE 实验证明电子取代基对分子内 CH/π 相互作用的影响
DOI：
10.1039/a909450d
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
M. Nishio
中科院分区：
文献类型：
--
作者：
H. Suezawa;Tsutomu Hashimoto;Kaho Tsuchinaga;Takashi Yoshida;T. Yuzuri;K. Sakakibara;M. Hirota;M. Nishio
为了证明CH/π相互作用的类氢键性质，通过测量1H NMR信号的NOE增强，研究了电子取代基对一系列能够形成CH/π相互作用的化合物的伸展构象和折叠构象之间平衡的影响.核Overhauser增强被证明是有用的，以确定的CH/π近端折叠构象的丰度。所有系列的能够具有CH/π相互作用的化合物的Hammett图给出负的ρ值。结合其他取代基效应（电负性取代基效应、CH给体效应、环尺寸效应和α-烷基取代基效应），确定了CH/π相互作用的离域相互作用和类氢键特征。
In order to demonstrate the hydrogen-bond-like character of the CH/π interaction, electronic substituent effects on the equilibria between the stretched and the folded conformers of series of compounds capable of forming CH/π interactions were examined by measurements of NOE enhancements of 1H NMR signals. Nuclear Overhauser enhancement is shown to be useful to determine the abundance of the CH/π proximate folded conformer. The Hammett plots of all series of the compounds capable of having CH/π interaction gave negative ρ values. Together with other substituent effects (effects of electronegative substituents, on the CH donor, of ring size, and of α-alkyl substituent), the involvement of delocalization interaction and the hydrogen-bond-like character of the CH/π interaction were established.