Action des derives du phosphore trivalent sur les composes α-cyano α-halo carbonyles : Orientation de la reaction entre un anion enolate et un cation halophosphonium

The factors responsible for the orientation in the reaction between an anion derived from an α-cyano α-haloketo compound with an halophosphonium cation are determined. Steric effects are important, but electronic effects are not negligible. This reaction is controlled more by frontier electron densities for cations derived from trialkyl or triarylphosphines than for cations derived from trialkylphosphites or trisdime´thylaminophosphine.