organometaal

Organometaal compounds, also called organometallic compounds, are chemical species that contain a direct bond between a carbon atom of an organic fragment and a metal atom. This carbon–metal bond can be covalent and is found in a wide range of structures, from simple alkyl or aryl groups bound to main-group elements such as magnesium or lithium to complexes of transition metals like iron, palladium, nickel, or platinum. The field encompasses reagents, catalysts, and materials, including Grignard reagents, organolithiums, metallocenes, and many catalytic complexes used in homogeneous catalysis.

A defining feature of organometallic chemistry is the presence of robust M–C bonds that enable the transfer of organic groups between molecules. Common classes include organomagnesium reagents (RMgX, Grignard reagents), organolithiums (RLi), various alkylidene and aryl–metal complexes, and metal-centered catalysts such as palladium, nickel, and rhodium complexes. Metallocenes, such as ferrocene, illustrate another important category where the metal is sandwiched between cyclopentadienyl rings. The bonding and reactivity of organometallics are governed by both the organic ligands and the electronic structure of the metal center.

Synthesis and reactions: organometaal compounds can be prepared from organohalides with magnesium or lithium, or via transmetallation from other metals. They participate in a broad array of transformations, including carbon–carbon bond formation in cross-coupling reactions (Suzuki, Negishi, Kumada, Stille), hydrofunctionalization, and polymerization catalysis. They also serve as key intermediates in many organic syntheses and industrial processes.

Safety and significance: many organometallic compounds are air- and moisture-sensitive, and some are pyrophoric or toxic, requiring inert-atmosphere handling and specialized solvents. The field sits at the interface of inorganic and organic chemistry and underpins much of modern catalysis, materials science, and synthetic methodology.