Abstract:

The relation between the ¹³C chemical shift of C=O in alkyl substitute d compound RXC=O and the polarizability effect index (PEI) of alkyl group R can  be expressed as
δ=a+b·ΣPEI(R)
where a and b are empirical constants. Regression analysis showed that the equat ion is a good expression for the ¹³C chemical shift of C=O change rule  with the  polarizabality effect index of alkyl group. The results also showed that the pol arizability effect index of alkyl group R increase the ¹³C chemical sh ift of C=O.

Key words: carbonyl compound, ¹³C chemical shift, polarizability effect, alkyl group