(Benzene)chromium tricarbonyl

(Benzene)chromium tricarbonyl is an organometallic compound with the formula Cr(C6H6)(CO)3.

This yellow crystalline solid compound is soluble in common nonpolar organic solvents.

The molecule adopts a geometry known as “piano stool” because of the planar arrangement of the aryl group and the presence of three CO ligands as "legs" on the chromium-bond axis.

For commercial purposes, a reaction of Cr(CO)6 and benzene is used: Complexes of the type (Arene)Cr(CO)3 have been well investigated as reagents in organic synthesis..[3] The aromatic ring of (benzene)tricarbonylchromium is substantially more electrophilic than benzene itself, allowing it to undergo nucleophilic addition reactions.

The resulting organolithium compound can then be used as a nucleophile in various reactions, for example, with trimethylsilyl chloride: (Benzene)tricarbonylchromium is a useful catalyst for the hydrogenation of 1,3-dienes.