Silyl-nitrogen compounds. X. Pathway of addition reactions in tetrasila-2-phospha-1-tetrazene

Tetrakis(trimethylsilyl)-2-phospha-1-tetrazene (Me3Si)(2)N-N(SiMe3)-P=N(SiMe3), (1) reacts with an alkyllithium RLi(R=Me, Bu) to form the P(III)amide (Me3Si)(2)N-N(SiMe3)-P(R)-N(SiMe3)Li which undergoes an intramolecular rearrangement at room temperature to give the imino-phosphoranide (Me3Si)(2)N-N(SiMe3)-P(R)(Li)=NSiMe3. The phosphoramide as well as the imino-phosphoranide react with Me3ECl (E=Si,Sn) to form the phosphine (Me3Si)(2)N-N(SiMe3)-P(Me)-N(SiMe3)(EMe3) and the phosphorane (Me3Si)(2)N-N(SiMe3)-P(Bu)(EMe3)=N(SiMe3), respectively. The former undergoes a slow rearrangement to form a phosphorane, whereas the tatter is stable.