The innovative synthesis technique unlocks a new class of planar organometallic compounds

With six Nobel Prize winners in the category, organometallic chemistry has been an area widely explored since the 1950s. However, the discovery of new classes of organomietal compounds remains a rare event.

A team of researchers from China and the United States has decided to change this by identifying a new class of organometallic compounds – three new planar annulnes centered on metal.

Cancels are cyclical hydrocarbons that contain the maximum number of simple carbon – carbon carbon carbon links possible, with a general formula C_nH_n for even a number of N or C_nH_{N + 1} For an odd number of n. The cancelled cancelled in this study consisted of 15 carbon atoms linked to an atom of transitional metal bone, in the center.

The new compounds have been reported in Nature.

The middle of the 20th century saw the rise of a new field of chemistry called organometallic, launched by the discovery of the ferrocène – a compound composed of two annulène rings with five carbons chasing a central iron atom. In most organomotallic compounds, a metal is coordinated π where it is above or below the plane plane.

Over the years, many exterior complexes have been synthesized, considerably influencing bond theory and finding various applications in scientific and industrial processes thanks to their useful catalytic, electrochemical and magnetic properties.

However, few metal-animulne complexes in the plane where the metal atom is located inside the ring and forms a bond σ (sigma) with carbon atoms rather than π bonds, have been reported.

The synthesis of these complexes has proven to be much more difficult due to several factors: the restrictions due to lower cancelled anions not having a central cavity large enough to accommodate a metal atom, larger cancelled out of the planarity because of their flexible structures and the need to break high carbon-hydrogen bonds and replace them with flexible bonds and need.

The new study overcomes synthetic obstacles to metallo-anlulnes in the plan by targeted molecular design and an intelligent synthetic way. Instead of trying to insert a metal into a cancel, the researchers built a frame cancels around a metal center.

The synthesis was carried out in several stages, starting with a molecular precursor containing a triple bond of osmium – reactive carbon, then to assemble carbon -carbon links around the metal atom via the cycloadition reaction. This led to the formation of Annulène metallic complexes in the plane (15), containing five merged rings joined by the central fragment of bis-phosphine osmium.

The most symmetrical molecule designed in the study was a metallo-anlulnene made up of five aromatic rings connected to five members. Using this as a parent structure, the researchers derived the iodized, chlorinated and nitrated version of metalo-annulnes in the plane. They also found that the phosphine ligands of the parent fraction can be exchanged, offering a versatile platform for more recent derivatives.

Researchers highlight that the high stability of plane cancelled centered on metal and their ability to be functionalized position them as promising constituent elements for materials science.

© 2025 Science X Network