Synthesis, Isolation, and Reactivity of a Phosphinidene Telluride.

The synthesis and isolation of a phosphorus(III) telluride is reported. The compound was accessed by means of a double bond metathesis reaction between an amido-functionalized phosphinidene oxide, BnArNP═O (Ar = bulky aryl substituent), with a silylene telluride, L(NMe2)Si═Te (L = PhC(NtBu)2). The resulting phosphinidene telluride, BnArNP═Te, exhibits a short P═Te bond (2.297(1) Å), resulting from a significant pπ-pπ orbital interaction between the phosphorus(III) and tellurium(-II) atoms. Key to the stabilization of this compound is the amido substituent associated with the phosphorus atom, which provides kinetic stabilization due to its steric bulk but also significant thermodynamic stabilization through negative hyperconjugation of the nitrogen atom lone pair into antibonding orbital interactions between phosphorus and tellurium. The title compound acts as a versatile phosphinidene transfer platform, accompanied by the extrusion of elemental tellurium to afford other phosphorus(III) compounds via transient phosphorus(V) intermediates.