A research group from the Institute of Chemical Technology (ITQ) – a joint center of the Higher Council for Scientific Research (CSIC) and the Polytechnic University of Valencia (UPV) – has developed a technology to obtain alkenes, organic molecules of wide industrial use, through from analogous molecules “up to ten times cheaper than those used now”.
Using small amounts of ruthenium as a catalyst, the scientific team has shown that it is a viable technology at an industrial level, producing the large-scale synthesis of commercial fragrances in collaboration with an international company in the sector. The new method is published in the journal ‘Nature Communications’.
Alkenes are hydrocarbons that contain a carbon-carbon chemical double bond. They abound in nature, and their chemical derivatives are products of great interest in the industry, since they are used for the production of millions of tons of detergents, lubricants, cosmetics, fragrances or polymers (plastics, tires…) a year.
Specifically, the alkenes used in the study are the so-called ‘internal alkenes’, which are obtained from analogous molecules called ‘terminal alkenes’.
The simplest way to obtain internal alkenes is through isomerization reactions (change the atoms in order) of terminal alkenes, but this requires high temperatures (more than 250 °C) and its products cannot be used in the fine chemical industry, in addition to produce unwanted ones.
Internal alkenes are also obtained by other more selective but less efficient synthetic methods, which use large quantities of products (catalysts, ligands, additives or solvents), which makes them not feasible to be implemented at an industrial level due to their high cost and the amount of waste they generate, they explain from the research institute.
The new method developed by the ITQ allows the synthesis of internal alkenes from their terminal analogs using amounts of catalyst (ruthenium) of parts per million, which makes it a viable technology to be used at an industrial level. “In fact, as mentioned in the article, we have used this methodology to carry out the large-scale synthesis of commercial fragrances in collaboration with a company in the sector,” Antonio Leyva-Pérez, CSIC researcher at ITQ, explains in a statement. who leads the study.
According to the CSIC scientist, current technologies to produce internal alkenes use acid catalysts at high temperatures, generating unwanted products, or rhodium catalysts, a metal ten times more expensive than gold. “Our new methodology allows us to obtain a wide variety of internal alkenes in a completely selective manner, that is, without the formation of other secondary products, which means that they can be used for many applications,” says Leyva-Pérez.
“Furthermore, small quantities, parts per million, of ruthenium species are used to obtain it, a material three times cheaper than gold, which makes it a very economical and viable process from an industrial point of view”, says the researcher. Since internal alkenes are widely used for a wide variety of transformations in the chemical industry, the use of this methodology has a wide range of possibilities.
The work is carried out in collaboration with the company International Flavors
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