Attempts to Rationalize the Chemical Reactivity of the 1–3 Dipolar Species Obtained when a Phosphite Reacts with Activated Ethylenic or Acetylenic Ketones or Esters

Abstract

- Addition of trivalent phosphorus compounds with α, β ethylenic ketones and esters leads to examples of prototropy or cyclisation or rearrangement with ring expansion from 5 to 7 atoms.

When trivalent phosphorus compounds react with acetylenic ketones and esters, the 1, 3 dipolar species can be trapped with an electrophilic reagent (aldehydes or the original acetylenic compound) or a protic reagent (alcohol, acid, amide, phenol, etc…) Ylides, phosphoranes, spirophos-phoranes and phospholes can be obtained.