Studies of Phosphazenes. Part $22.^1$ High-field Nuclear Magnetic Resonance Investigation of Novel Isomeric Oxophosphazadienes

The reaction of $N_3P_3$$( NPPh_3)$$Cl_5$ with an excess of methoxide yields the 'hydroxy'-derivatives, $N_3P_3$$( NPPh_3)$ $(OMe)_4$,(OH) and $N_3P_3$$( NPPh_3)$ $(OMe)_3$,$(OH)_2$, in addition to the fully methoxylated derivative $N_3P_3$$( NPPh_3)$ $(OMe)_5$. The analogous reaction of gem-$N_3P_3$$( NPPh_3)$ $(Nme_2)$ $Cl_4$ with ethoxide affords $N_3P_3$$( NPPh_3)$ $(NMe_2)$ $(OMe)_4$ and $N_3P_3$$( NPPh_3)$ $(NMe_2)$ $(OMe)_4$,(OH). The 'hydroxy'-derivatives exist in their oxophosphaza-tautomeric forms. For the 'monohydroxy'-compounds, the presence of a pair of cis- and trans-oxophosphazadienes is established from $^1H$ and $^{31}P$ n.m.r. spectroscopic data