Revolutionizing chemistry - reaction by reaction
New applications for familiar chemicals
Advertisement
Professor Daniele Leonori, Chair of Organic Chemistry III at RWTH Aachen University, has published research findings in the journal Nature catalysis that open up new avenues for more cost-effective and sustainable processes in chemical synthesis. The publication entitled "Excited-state configuration controls the ability of nitroarenes to act as energy transfer catalysts" concludes a series of studies. The work sheds new light on the role of nitrobenzenes and shows how these long-established raw materials can be used in synthetic chemistry in a much more versatile way than before.
New applications for well-known chemicals
Nitrobenzenes have been used for almost two centuries, primarily as industrial raw materials for foams, rubber and pharmaceuticals. In recent years, however, Leonori and his team have been able to show that these inexpensive and widely used molecules can do much more than previously assumed. The new findings open up additional application possibilities for research and industry and have the potential to make chemical processes safer, more economical and more sustainable.
Ozone-based reactions rethought
When it comes to ozone, many people first think of the protective ozone layer in the Earth's atmosphere. However, ozone plays a central role in the chemical industry - for example in the ozonolysis of adipic acid, an important step in the production of detergents. In this reaction, a carbon-carbon double bond is split into two fragments. However, ozone is technically demanding and poses considerable safety risks, as ozonolysis reactions can produce explosive products.
In the article "Photoexcited nitroarenes for the oxidative cleavage of alkenes" published in Nature in 2022, Leonori and other researchers showed that nitrobenzenes can act as "ozone substitutes" when irradiated with visible light. Light activation causes the molecules to enter an excited state that enables reactions that could previously only be carried out with ozone. The potential of this discovery was obvious: as De Mayo-Parasram-Leonori alkene photooxidation, the method quickly attracted international attention and is now used as part of undergraduate chemistry courses in several countries.
A knife that cuts an apple - but not a banana
The ozonolysis of aromatic hydrocarbons is considered extremely promising, as it could open up new synthesis routes for materials, active ingredients and dyes. In practice, however, there is a fundamental problem: during the reaction, alkenes are formed that are significantly more reactive than the aromatic starting compounds. This leads to overreactions and unusable product mixtures. Put simply, as soon as the reaction starts, the newly formed product reacts faster than the original substrate. The central question was therefore: How can the starting material be activated in a targeted manner, even though the resulting product is more reactive?
Leonori's team investigated whether this limitation could be overcome with the help of nitrobenzenes. By specifically adapting the structure of the nitrobenzenes and activating them with visible light, they succeeded in reversing the usual reactivity pattern: This allowed them to selectively cleave the less reactive aromatic ring while retaining the more reactive alkene. An editor of the journal Science, in which the work was published in March 2025 under the title "Excited-state configuration of nitroarenes enables oxidative cleavage of aromatics over alkenes", summarized the result as follows: The researchers had found "a knife that cuts an apple, but not a banana".
A more cost-effective and sustainable method for catalyzing chemical reactions
Catalysts are a cornerstone of modern chemical production, but many of the most efficient ones are based on rare transition metals such as iridium or ruthenium. In their latest Nature Catalysis publication, the researchers show that nitrobenzenes themselves can be used as light-activated organic catalysts. These molecules act like small antennas: They absorb visible light and transfer the absorbed energy to organic substrates. In this way, they enable reactions that typically require metal catalysts.
In several model reactions, the team showed that these simple, widely used organic compounds can match the performance of established heavy metal catalysts. Although the research is still at an early stage, the prospects are far-reaching. Nitrobenzenes can be easily varied structurally, which could enable them to be incorporated into larger biomolecules in the future in order to control reactions in complex environments. Another advantage is the cost: nitrobenzenes are up to 4,000 times cheaper than conventional metal catalysts - a factor that makes them particularly attractive for large industrial sectors such as agrochemicals.
Note: This article has been translated using a computer system without human intervention. LUMITOS offers these automatic translations to present a wider range of current news. Since this article has been translated with automatic translation, it is possible that it contains errors in vocabulary, syntax or grammar. The original article in German can be found here.
Original publication
Other news from the department science
Most read news
More news from our other portals
See the theme worlds for related content
Topic world Synthesis
Chemical synthesis is at the heart of modern chemistry and enables the targeted production of molecules with specific properties. By combining starting materials in defined reaction conditions, chemists can create a wide range of compounds, from simple molecules to complex active ingredients.
Topic world Synthesis
Chemical synthesis is at the heart of modern chemistry and enables the targeted production of molecules with specific properties. By combining starting materials in defined reaction conditions, chemists can create a wide range of compounds, from simple molecules to complex active ingredients.