E-2-benzylidenebenzocycloalkanones. III. Studies on transmission of substituent effects on IR carbonyl stretching frequencies and 13C NMR chemical shifts of E-2-(x-benzylidene)-1-indanones. Comparison with the IR data of Ε-2-(x-benzylidene)-1-indanones, -tetralones, and -benzosuberones

Abstract Single substituent parameter and dual substituent parameter analysis was applied to study transmission of substituent effects on IR carbonyl stretching frequencies of E -2-(X-benzylidene)-1-indanones ( 3 ), -tetralones ( 4 ), and -benzosuberones ( 5 ). Similar analyses were performed for selected 13 C NMR chemical shifts of some E -2-(X-benzylidene)-1-indanones ( 3 ). For a better understanding of the results semiempirical and ab initio quantum chemical calculations were performed to determine the preferred geometry and to calculate the theoretical 13 C NMR chemical shifts of the selected compounds ( 3 ). The differences among the regression coefficients were discussed in terms of the relative importance of the field and resonance effects for the analogous enones with different geometries.