摘要
烷基的电子效应尽管因其所连环境的不同而有异,但是认为烷基此一时是给电子的诱导效应,彼一时又是吸电子的诱导效应,以及认为烷基的超共轭效应仅存于溶液体系中是站不住脚的。本文作者认为,烷基在不带电荷的中性有机结构中,通过诱导效应总是吸电子的,但当它与不饱和结构,包括带正电荷的原子或原子团相连时,还通过Baker—Nathan超共轭效应,乃至空间超共轭效应起供电作用。只是这种供电作用,在溶液中,由于溶剂化作用,其相对强弱遵循Baker—Nathan顺序;而在气相或溶剂化作用很小的溶液中则遵循反Baker—Nathan顺序.
Although the electronic effects of an alkyl group vary with the circumstances concerned, it does not hold water to consider that an alkyl group is an electron-withdrawing group by inductive effect at one time,an electrondonating group at another time,and hyperconjugation lies only in solution. In this paper we hold that an alkyl group is an electron-withdrawing group by inductive effect when it is connected to a saturated system,but it is an electron-donating group when it is connected to an unsaturated system or an atom having a positive charge by hyperconjugation, and even space-h yperconjugation. However, the relative strength of these electron donors follows the Baker-Nathan order by solvation effects in solution, and the Baker-Nathan anti-order in gas phase.
出处
《阜阳师范学院学报（自然科学版）》
1991年第1期13-19,共7页
Journal of Fuyang Normal University(Natural Science)
关键词
烷基
电子效应
诱导效应
alkyl groups
electronic effects
inductive effect
hyperconjugation
space-hyperconjugation
