A stable (amino)plumbylene-substituted phosphaketene 3 was synthesized by the successive reactions of PbCl 2 with two anionic reagents (lithium amidophosphine and NaPCO). Of particular interest, the thermal evolution of 3, at 80 °C, leads to the transient formation of corresponding amino-and phosphanylidene-phosphaketenes (6 and 7), via a reductive elimination at the Pb II center forming new NÀ P and PÀ P bonds. Further evolution of 6 gives a new cyclic (amino)phosphanylidene phosphorane 4, which shows a unique reactivity as a phosphinidene. This result provides a new synthetic route to phosphinidenes, extending and facilitating further their access.

Phosphine-stabilized Pb(II) cations, generated by chloride abstraction from chloroplumbylene 1, readily react with Lewis bases (L) such as phosphines and amines to give the corresponding donor−acceptor complexes 3. These complexes 3 react with phenylacetlylene via alkyne insertion into the Pb−L bond to afford the corresponding vinylplumbylenes 4. Of particular interest, the stable complex 4-HNiPr 2 (with a secondary amine) can be used as a hydroamination catalyst of phenylacetylene.