Polarity of para-disubstituted benzene derivatives: a correlation analysis of the substituent effect

Аннотация

The article is concerned with the influence of resonance donor substituents R_D on the dipole moments μ of molecules 1,4-R_DC₆H₄R_A containing resonance acceptor groups R_A (CF₃, CN, COCH₃, NO₂ or COH) and grouped in five reaction (indicator) series. Generally, the μ values depend on the inductive, resonance, and polarizability effects of the substituents R_D. Strengthening of the resonance acceptor properties of the R_A groups leads to weaker conjugation between the substituents R_D and the π-system.