- Date 2024-05-03
The chemical industry has been using a reaction with explosive chemicals for over 100 years - now Mülheim scientists have discovered a safer alternative.
Aryldiazonium salts, which have been used for 140 years, are very reactive and therefore extremely useful for producing other compounds. However, the high reactivity means that isolated aryldiazonium salts are not very stable and can therefore react unintentionally and sometimes explosively. On December 23, 1969, there was a particularly serious explosion involving these chemicals at Ciba AG in Basel killing three workers and injuring 31.
A team led by Prof. Dr. Tobias Ritter, director at the Max Planck Institute for Carbon Science, has now succeeded in making the risky chemistry with aryldiazonium salts significantly safer. The Mülheim Protocol not only makes the use of these compounds less dangerous, but also potentially opens up opportunities for the development of new reactions.
The new strategy is based on the use of a natural process, nitrate reduction, which is carried out in plants. The researchers managed to imitate the natural process in a test tube and combine it with aryldiazonium chemistry to develop a safer synthesis method.
Because the researchers combine several steps in their new protocol, large concentrations of the dangerous substance do not arise in the first place. Also, the technology utilizes chemicals that are used in large quantities in the fertilizer and fuel industries. This could make the synthesis route extremely interesting for companies in the chemical industry as it means lower production costs.
The method is based on a chance discovery as part of another project. It is also exciting scientifically because new chemical approaches can now be pursued, that would not be readily possible with the classic method due to the high risk of explosion and instability of the connections.
The original publication “Nitrate reduction enables safer aryldiazonium chemistry” was published in the journal Science.
Source: Max-Planck-Institut für Kohlenforschung, News „Safer alternative for an explosive reaction“, April 25, 2024 https://www.kofo.mpg.de/983464/2024-04-25-scienceritter