The synthesis of 1‐aminoalkylphosphonic acids. A revised mechanism of the reaction of phosphorus trichloride, amides and aldehydes or ketones in acetic acid (Oleksyszyn reaction)

The mechanism of the amidoalkylation of trivalent phosphorus compounds in acetic acid has been reinvestigated. Evidence is presented that 1‐(acylamino)alkyl acetates 5 and not N , N ′‐alkylidenebisamides 2 are the intermediates in this reaction. Supporting literature analogies are discussed. This paper also describes a convenient procedure for the preparation of crude (acylamino)alkyl alkanoates 5 , which are excellent amidoalkylating agents. The usefulness of these reagents is demonstrated by a simple two‐step “one pot” synthesis of 1‐aminoalkylphosphonic acids 1 .