Chemists from RUDN University and INEOS RAS had a unique catalysts on the basis of two different metals

Chemists from RUDN University and INEOS RAS had a unique catalysts on the basis of two different metals

A team of chemists from RUDN University and INEOS synthesized two heterometallic clusters at once with an efficiency close to 100%. These compounds are used as catalysts in pharmaceuticals, polymer production and other areas of the chemical industry.

A metal cluster is an association of several metal atoms, between which there is a significant interaction. Clusters that consist of atoms of different metals are called heterometallic — they can be catalysts in organic reactions, for example in pharmaceuticals and polymer production. However, creating such clusters is not easy. The chemists of RUDN and INEOS described how it is possible to efficiently produce heterometallic clusters from an “ordinary” metal cluster consisting of three rhodium atoms.

“Rhodium is well known as a catalytic metal. There are many organic processes that are catalyzed by rhodium-based metal clusters. However, most approaches for the synthesis of heterometallic clusters are random and give a low yield of the desired product. We managed to create heterometallic clusters of rhodium with high reaction efficiency,” says Olga Chusova, PhD, researcher at the research center “Crystal Chemistry and Structural Analysis” of the RUDN University.

The chemists used a cluster of three rhodium atoms that join together to form a triangle. Ligands — molecules that dictate the behavior of rhodium atoms — are attached to the vertices and sides of this triangle. The detailed selection of ligands in both the initial cluster and the reagents allowed chemists to create new heterometallic clusters. The fact is that compounds feel better with some ligands than with others. In this case, the addition of metalloelectrophil as a reagent, which contains an atom of another metal with a lack of electrons, made it possible to create a new complex that consists of atoms of different metals — a heterometallic cluster. Instead of a triangle, a tetrahedron is formed — at its vertices three rhodium atoms and another gold or cobalt atom.

Such a mechanism provided almost one hundred percent efficiency of the reaction — that is, the actual amount of the obtained heterometallic cluster almost coincided with the theoretically calculated one (81% of the theoretical value for the cluster with cobalt and 93% — with gold). It is noteworthy that it worked equally well, despite the fact that metalelectrophiles with gold and with cobalt have different structures.

“Although metalloelectrophiles have different electronic structures, they both react with a triangular rhodium cluster and form stable tetrahedral clusters. This phenomenon is due to the unique structure of the original rhodium cluster, as it can provide a different number of electrons depending on the needs of the metalelectrophile. In this case, the gold derivative needed only two electrons to achieve the dream, and the cobalt derivative needed as many as six,” says Olga Chusova.

According to scientists, the discovery will increase the efficiency of the synthesis of catalysts based on heterometallic clusters for the chemical industry.

The study is published in the Journal of Organometallic Chemistry.

International scientific cooperation View all
03 Nov 2017
The main goal of the RUDN University and UNISDR Office for Northeast Asia and Global Education and Training Institute for Disaster Risk Reduction at Incheon (UNISDR ONEA-GETI) cooperation is to obtain knowledge about disaster risk reduction and international experience in this area for creating training courses for basic and additional professional education in RUDN
30 Jan 2018
The conference on international arbitration, where law students from European universities simulate court proceedings and alternately defend the interests of the respondent and the orator.
Similar newsletter View all
07 Jul
RUDN University Biologist: salted water saves fish from stress when transporting

RUDN University biologist with colleagues from Brazil and Iran found how to alleviate the stress of fish during transportation. It turned out that this can be achieved with salted water.

20 Apr
RUDN University agronomists increased wheat yield by 65%

RUDN University agronomists have proposed a new scheme for fertilizing winter wheat, which allows increasing the yield by 68%. The key to this is in the combination of nitrogen and growth regulators.

20 Apr
RUDN Biologists Study Live Microorganisms in Toxic Liquids for Metalworking

RUDN biologists have studied microorganisms that can survive in metalworking fluids. The results will allow “picking up” bacteria and fungi that can process toxic waste fluids into a harmless product.

Similar newsletter View all