Scope and limitations of the aromatic anionic [1,3] P-O to P-C rearrangement in the synthesis of chiral o-hydroxyaryl diazaphosphonamides

The influence of numerous parameters in the aromatic anionic [1,3] P-O to P -C rearrangement in the synthesis of chiral o-hydroxyaryl diazaphosphonamid es has been envisaged. Various strong bases such as LDA, sec-BuLi, tert-BuL i have been conveniently used. The scope of the regioselectivity of the rea rrangement has been particularly studied varying the nature of the phenoxy group implied in this reaction. A totally diastereoselective P-S to P-C mig ration rearrangement has been observed starting from a thiophosphonamide pr ecursor. Moreover, starting from a phenylthio substituted phosphonamide, a totally diastereoselective P-S to P-C rearrangement of the diazaphosphonami de moiety has also been demonstrated. (C) 2000 Elsevier Science Ltd. All ri ghts reserved.