Phospholidines incorporating a beta N-sulfonylaminoalcohol moiety: first observed selectivity of phosphorus heterocycle aminolysis in the presence of water.

Eleven 2-oxo or 2-thioxo 3-sulfonyl 1,3,2-oxazaphospholidines were synthesized in one step by condensing P(IV) dichlorides with N-sulfonyl-ethanolamines, or -aminothexylalcohols or -ortho-aminophenols. These compounds, in contrast to all other phosphorus heterocycles studied so far, reacted easily with amines, sometimes selectively in the presence of water, leading to the corresponding amides. The results are rationalized by the involvement of the addition-elimination mechanism of phosphorylation with direct collapse of the primary zwitterionic intermediate formed by the amine attack on phosphorus.