Abstract Aminomethanephosphonate. Mercury EDTA Dehydrogenation. Lactam. Formamide, Aminoalkylation Aminophosphonates 1-5 are dehydrogenated with mercury EDTA to the corresponding lactams 6-9 and surprisingly to the formamide derivative 10, The different rate of ester hydrolysis of these acylamine compounds, the steric requirements and the reaction mechanisms are dis-cussed.