On the reactivity of organophosphorus compounds: Part IV. The alkaline hydrolysis of some O‐phosphylated 2‐pyridine oximes

Abstract
The rates of alkaline hydrolysis of a number of O‐phosphylated 2‐pyridine oximes, C5H4NC(R1)NOP(O)R2R3, at different temperatures have been determined. The second‐order rate constants and the values of ΔH* and ΔS* are reported. Two parallel pathways of hydrolysis are observed: a nucleophilic substitution reaction on phosphorus (SN2P) generating the oxime and the parent acid and an elimination reaction of the Beckmann type (E2 or ElcB) producing the nitrile and the parent acid. The effects of the groups R1, R2 and R3 on the rates of substitution and elimination are discussed.