Azaphosphiridine oxides intermediates

Methyl P-bromomethyl-A-r-butylphosphonamidate (360) has been found to rearrange upon treatment with methoxide to give dimethyl f-butylaminomethylphosphonate (362) and dimethyl iV-r-butyl-iV-methylphosphoramidate (363). The authors have proposed that the products are derived from an azaphosphiridine oxide intermediate (361) by nucleophilic attack at phosphorus and cleavage of the P-N or P-C bond, respectively. ... 

Harger. M.J.P., and Sreedharan-Menon, R., Alkoxide induced leanangement of alkyl bromometh-ylphosphonamidates. Steric influences on the direction of ring opening of the azaphosphiridine oxide intermediate. J. Chem. Soc., Perkin Tnins. I, 211, 1998. 

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