Decacarbonyldihydridotriosmium is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 with the formula H₂Os₃(CO)₁₀. This purple-violet crystalline air-stable cluster is noteworthy because it is electronically unsaturated

Saturation (chemistry)

In chemistry, saturation has six different meanings, all based on reaching a maximum capacity...

 and hence adds a variety of substrates.

Structure and synthesis

The trinuclear cluster features an isosceles triangular array of metals with one short edge (r_Os-Os = 2.68 Å), which is spanned by the two hydride ligands, and two longer edges (r_Os-Os = 2.81 Å). It can be described as Os(CO)₄[Os(CO)₃(μ-H)]₂. The bonding in the Os₂H₂ subunit has been compared to the 3-center, 2e bonding in diborane. It is prepared by purging a solution of Os₃(CO)₁₂

Triosmium dodecacarbonyl

Triosmium dodecacarbonyl is a chemical compound with the formula Os312. This yellow-colored metal carbonyl cluster is an important precursor to organo-osmium compounds...

 in octane

Octane

Octane is a hydrocarbon and an alkane with the chemical formula C8H18, and the condensed structural formula CH36CH3. Octane has many structural isomers that differ by the amount and location of branching in the carbon chain...

 (or other inert solvent of similar boiling point) with H₂

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

.

Os₃(CO)₁₂ + H₂ → Os₃H₂(CO)₁₀ + 2 CO

Reactions

The cluster reacts with a wide range of reagents under mild conditions. Illustrative is its reaction with [Ni(CO)(C₅H₅)]₂ to give [Ni(C₅H₅)]₃Os₃(CO)₉. With diazomethane

Diazomethane

Diazomethane is the chemical compound CH2N2. It is the simplest of diazo compounds. In the pure form at room temperature, it is a extremely sensitive explosive yellow gas, thus it is almost universally used as a solution in diethyl ether...

, it gives Os₃(CO)₁₀(μ-H)(μ-CH₃), exhibiting an agostic interaction

Agostic interaction

Agostic interaction is a term in organometallic chemistry for the interaction of a coordinately-unsaturated transition metal with a C-H bond, when the two electrons involved in the C-H bond enter the empty d-orbital of a transition metal, resulting in a three-center two-electron bond. Many...

, the first identified in a metal cluster.