Alkali metal bis(trimethylsilyl)phosphanides react with different halogenophosphorus compounds to form multiple P-P bonds.
['] The alkali metal phosphanide serves as a reagent for metalation of silylphosphorus functionalities with the elimination of P(SiMe,), and as a source for the central phosphorus atom in the resulting tri-and isotetraphosphanes. Our interests have focused on the extension of the above concept by the use of transition metal halides and the heavier homologues [E(SiMe,),]-(E = As, Sb, Bi) .Iz1 The paramagnetic W'" halogenide [ (N,N)WC1][31 1 b [(N,N) = N(CH,CH,NSiMe,),] serves as an ideal starting material in both respects. With this species and the corresponding molybdenum compound 1 a,14] Schrock et al. were able to synthesize the first examples of compounds containing a metal-phosphorus triple bond (2) [Eq. (a)] that were structurally characterized.['] At the same time Cummins et al. reported the synthesis of a complex containing a Mo-P triple bond by using [Mo(NAr'R),] (Ar' = 3,5-C,H,Me,, R = C(CD,),CH,) and white phosphorus as starting CI P la: M = Mo l b : M = W 2a: M = Mo