NUCLEOPHILIC SUBSTITUTION REACTION OF BENZYL BROMIDE WITH N,N-DIMETHYLANILINE: SIGNIFICANCE OF EQUILIBRIUM CROSS-INTERACTION CONSTANT

Article abstract of DOI:10.1002/poc.610071006

Kinetic studies on the reversible reactions of benzyl bromides with N,N-dimethylanilines were carried out for both the forward (k_f) and reverse (k_r) directions.The equilibrium constants, K were calculated using the ratio k_f//k_r and the equilibrium cross-interaction constant, ρ^e_XY was determined.The ρ^e_XY value was shown to represent a maximum intensity of interactions between substituents X and Y through covalent bonds within a molecule.The normalized values of ρ_X (ρ_nuc) and ρ_XY indicate that in the transition state the fractional development or loss of polar and resonance interactions in the benzyl system are imbalanced or non-perfectly synchronized.In the forward reaction the fractional loss of resonance interaction becomes enhanced, whereas in the reverse reaction the fractional development of resonance interaction lags behind the corresponding changes of polar interaction by ca 45percent.