Tetrylenes are Able to Discern between Isomeric Structures of Unsaturated Osmium(IV) Polyhydrides.

Hexahydride OsH(PPr) (1) releases H to form the isomeric tetrahydrides 2 a and 2 b of general formula OsH(PPr). Tetrylenes E{N(SiMe)} (E=Ge, Sn) are able to selectively trap these isomers distinguishing between them. Tetrylene Ge{N(SiMe)} catches 2 b to generate OsH{Ge[N(SiMe)]}(PPr) (3), which has a piano stool geometry, while Sn{N(SiMe)} captures 2 a to give OsH{Sn[N(SiMe)]}(PPr) (4) with the donor atoms defining a pentagonal bipyramid around the osmium center.