nate and trimethylphosphine, affording N-phosphonionitrilimine 5 and phosphorus ylide 6 in 51 and 95% yields, respectively. [Bis(diisopropylamino)thioxophosphoranyl][bis(diisopropylamino)phosphino]diazomethane (8) also reacts with TCBQ leading to 4 (90% yield) via 3. This result is rationalized by the formation of the (thioxophosphoranyl)(phosphoranyl)diazomethane 9, which is in equilibrium with the