摘要
4-羟基-2,2,6,6-四甲基哌啶-1-氧自由基(4-OH-TEMPO)电子自旋共振的超精细耦合常数AN与溶剂极性的微观反应常数ET(30)和溶剂受体数AN呈现线性正相关.并且在介电常数或偶极矩接近时,含卤溶剂中超精细耦合常数AN普遍偏高.除了一般的溶剂效应外,在含卤溶剂中超精细耦合常数AN偏大的原因与专属性的卤键作用有关.理论计算结果辅助印证了这一结论.
The hyperfine splitting constants,AN,of electron spin probe,4-hydroxy-2,2,6,6-tetramethyl-1piperidin-1-yloxy,free radical（4-OH-TEMPO） show positive linear correlation with model reaction pa-rameters of solvent polarity,ET（30） and solvent acceptor number（AN）.Moreover,generally,AN values are higher in halogenated than non halogenated solvents as dielectron constant or dipole moment is near.Be-sides the general solvent effect on AN values,larger AN values can be attributed to the specific halo-gen-bonding between N-O free radical and halogenated solvent molecule.The calculation shows the oc-currence of C-Cl…O between chloroform or dichloromethane and free radical molecules.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2011年第11期1375-1380,共6页
Acta Chimica Sinica
基金
国家自然科学基金(Nos.20675009
90922023)
北京市自然科学基金(No.2093037)资助项目
关键词
卤键
电子自旋共振
专属性溶剂效应
含卤溶剂
溶剂受体数
halogen-bonding
electron spin resonance
specific solvent effect
halogenated solvent
solvent acceptor number
