Abstract

In the title compound, nonacarbonyl-1? 2C,2? 3C,3? 4C-?-hydrido-1:2? 2H-?-(N-methylcarboxamido)-1:2? 2O:C-(N-trimethylamine-1?N)triosmium(3 Os-Os), [Os 3H-(C 2H 4NO)(C 3H 9N)(CO) 9], the MeHNCO ligand forms a ? 2-C:O bridge between two metal centers, which are also linked by a ?-hydride ligand. These two groups are at opposite sides of the plane defined by the Os atoms. Bond lengths between Os atoms are 2.8149 (8), 2.8777 (8) and 2.9278 (8) Å. The structure shows two metal centers which are heptacoordinated and one which is hexacoordinated.