Density functional study of the relative reactivity of the carbonyl group in substituted cyclohexanone

Theoretical investigation was performed to study the effect of substitution of B, N, O, S, Se and Si, in six-member ring of cyclohexanone on the reactivity of the carbonyl group. All the computations were done at B3LYP/6-311++G∗∗ level of theory. Bond orders and charges of candidate molecules are calculated by using natural bond orbital (NBO) and atom in molecule (AIM) analyses. Relative electrophilicity (RE) and relative nucleophilicity (RN) of cyclohexanone and its derivatives are evaluated on the basis of natural population and atom in molecule analyses. It is observed that RE and RN extracted from both atom in molecule and natural population based charges produce nearly the same trends. On the basis of the current theoretical calculation it appears that maximum values of the electrophilicity and neucleophilicity belong to the molecules which have the more nonbonding interactions. There is a nearly good linear relationship between global electrophilicity and maximum number of electron transfer. The occurrence of negative Fukui function is also supported by the present study.