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化学学报
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化学学报 ›› 1965, Vol. 31 ›› Issue (6): 523-525. 上一篇    下一篇

饱和脂肪族羰基化合物的n→π*吸收峯位移与取代基常数间的定量关系

楊丕鹏   

  1. 云南大学化学系
  • 投稿日期:1965-06-14 发布日期:2013-06-03

A QUANTITATIVE RELATIONSHIP BETWEEN THE SHIFT IN THE n→π* ABSORPTION MAXIMA AND THE SUBSTITUENT CONSTANTS IN SATURATED ALIPHATIC CARBONYL COMPOUNDS

YANG PI-PENG   

  1. Department of Chemistry, Yunnan University
  • Received:1965-06-14 Published:2013-06-03

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Borrell[1]曾认为在饱和脂肪族羰基化合物中,若与羰基直接相连原子的电负性愈大,则羰基氧原子上的孤电子对愈不易激发,故其电子光谱n→π*吸收峯将移向短波方向,并由一些实验数据发觉相对频率位移△v 和原子电负性值间有线性关系。

The shift △v of the n→π* absorption maxima in saturated aliphatic carbonyl compounds is correlated by the empirical equation
△v=104∑[σ1-σR(σR+] (in wave numbers)
where σ1 and σR are Taft's inductive and resonance parameters respectively.σR+, which is equal to σP+-σ1,is used when the substituent is direct polar conjugated with the carbonyl group, and σP+ is Brown's electrophilic substituent constant.