The synthesis and base-induced rearrangements of alpha-halophosphonamidates.

The work described in the thesis is concerned with the preparation and rearrangement of alpha-halophosphonamidates. The introduction reviews some of the important examples of Favorskii and Ramberg-Backlund rearrangements which illustrate the suspected mechanism and synthetic utility of these reactions. Analogous rearrangements in Organophosphorus chemistry have been reported, but there are few such examoles in the literature. The Discussion describes the synthesis of alpha-halophosphonamidates, by the conversion of the corresponding alpha-halophosphonic dichloride into the phosphonamidate by one of several variations. The effect of base on the phosphonamidates is described. Where reaction had occurred the products could be explained by the postulation of a three-membered ring formed from the loss of the elements of hydrogen halide from the alpha-halophosphonamidate. The nature of the products depended upon the direction of the ring- opening, which in turn depended upon the relative stability of the anions formed in ring-opening. By making several variations in the structure of the alpha-halophosphonamidate under study, an insight into the finer details of the mechanism is possible. The experimental conditions which have been employed in relation to the above work are described in the final section.