A Lead-μ 2 -Tetrylide Complex with Osmium(IV) Terminal Components.

A bare lead atom is a σ-donor ligand capable of linearly bonding and stabilizing two units of a classical polyhydride complex, with a high-valent metal center. As a proof of concept, we have prepared and characterized the μ 2 -tetrylide complex (P i Pr 3 ) 2 H 4 Os═Pb═OsH 4 (P i Pr 3 ) 2 in the reaction of OsH 6 (P i Pr 3 ) 2 with Pb{N(SiMe 3 ) 2 } 2 . Although the Pb-Os bonds exhibit electrostatic interaction, the main orbital interactions result from two dative σ bonds from the lead atom to the osmium centers. The latter also provide much weaker π-backdonations.