Quelques remarques relatives aux équations linéaires de Hammett et de Winstein et Grunwald

Abstract

Abstract A paraboloid hyperbolic type equation is proposed to correlate the S N 1 solvolysis rates of organic halides. It is shown that it is the generalization of both Hammett and Winstein‐Grunwald equations. A second limiting mechanism (S N 2 lim.) is introduced and thus completes the scale of S N mechanisms. It is suggested that the Hammett and Winstein‐Grunwald linear equations should be satisfactorily verified only by reactions following, at least approximately, a limiting mechanism (S N 1 or S N 2 lim.). A statistical distribution of mechanisms is suggested in order to account for some results related to borderline cases; this should prove to be a useful extension to the concept of plurality of mechanisms.