Studies of phosphazenes. Part 33. Thermal rearrangement of alkoxy(p-methylphenoxy)cyclophosphazenes: a synthetic route to oxocyclophosphazanes, phosphazadienes and phosphaz-1-enes

Abstract

The aryloxy(alkoxy)cyclotriphosphazenes N₃P₃(OR)_6–m(OC₆H₄Me-p)_n(R = Me, n= 1–3; R = Et or CH₂Ph, n= 3) rearrange on heating to give trioxocyclotriphosphazanes; the di- and mono-methoxy derivatives, N₃P₃(OMe)_6–n(OC₆H₄Me-p)_n(n= 4 or 5), yield dioxophosphaz-1-enes and an oxophosphazadiene respectively. The ¹H, ¹³C and ³¹P NMR data for the starting materials and the products are presented. No evidence has been found for partially rearranged products. The geometrical disposition of the aryloxy groups in the starting material is retained in the rearranged products. Some aspects of the mechanism of the thermal rearrangement are discussed.