RUDN University chemist created new catalysts for click reactions

RUDN University chemist created new catalysts for click reactions

A chemist from RUDN University has created a series of catalysts for click chemistry. These reactions are widely used in the synthesis of biologically active substances, as well as in biological and medical research. New catalysts produce a yield of 99%. They are based on cyclodextrin and copper ions.

Click chemistry methods are used to synthesize libraries of substances with high chemical diversity, which is important when developing new drugs. These reactions are necessary for introduction of labels (for example, fluorescent ones) into biological macromolecules, proteins, and DNA molecules. This is used in biological and medical research.

The most commonly used click chemistry reaction is the addition of a substance that contains a carbon-carbon triple bond (alkine) to a compound containing a fragment with three nitrogen atoms in a row (azide). The classic version of the reaction involves the use of copper in oxidation state (I) as a catalyst. For this, ions of copper (II) and an excess of a reducing agent are introduced into the reaction, or copper (I) is used and the reaction is conducted with protection against oxygen, which imposes certain restrictions on the application of this reaction.

A chemist from RUDN University Rafael Luque and his colleagues have developed a series of catalysts with copper ions attached to the surface of silica gel particles using cyclic cyclodextrin oligosaccharide. Cyclodextrin consists of seven glucose molecules closed in a cycle. Inside the cycle there is a container that can hold the copper ion and increase its catalytic activity. Ultrasound irradiation was used to facilitate the binding of cyclodextrin to the surface of silica gel.

The effectiveness of the created catalysts was evaluated on a model reaction of phenylacetylene with benzylazide. The researchers managed to achieve a yield of the reaction product of more than 99%. The yield with copper (II) acetate was 14%, and in the case of copper (II) sulfate, the reaction did not occur at all. The method for producing the catalyst is simple, safe for the environment, and cheap; its use does not require to add reducing agents or oxygen-free conditions. The catalysts can find application in the pharmaceutical industry and in biomedical research.

The paper was published in the journal Molecules.

News
All news
Science
09 Jun
Multilingual Education during COVID-19: University Teachers from Several Continents and 18 Countries Explored Common and Specific Features of Remote Training

The RUDN University Academic Council Commission on Foreign Languages held its June research seminar in cooperation with international community of language teachers who became part of the international pro-bono project on challenges and solutions to foreign languages training during COVID-19.

Science
07 Jun
RUDN University Biologists Studied the Effect of Jungles on Global Warming

Biologists from RUDN University described the role of tropical rainforests in the production of methane, the second most harmful greenhouse gas after CO2. It turned out that some areas of rainforests not only consumed methane but also emitted it.

Science
04 Jun
Russian Chemists Suggested a Method for Producing Metal-Based Catalysts with Unparalleled Efficiency

A team of chemists from RUDN University and Nesmeyanov Institute of Organoelement Compounds (INEOS) synthesized two heterometallic clusters with almost 100% efficiency. These compounds can be used as catalysts in pharma, production of polymers, and other branches of the chemical industry.