Researchers have developed an environmentally friendly method for a key process used in the production of pharmaceuticals and other important chemicals that only leaves water as a byproduct, opening up new possibilities for drug discovery and production.
Scientists at the University of Nottingham’s Centre for Sustainable Chemistry are working to develop environmentally sustainable chemical processes that use much less energy and generate little or no waste when compared to current industrial technologies.
As part of this programme, a research team led by Dr Ross Denton and in collaboration with GSK have been working on a process known as the Mitsunobu reaction after its inventor Oyo Mitsunobu, to improve its environmental sustainability. This reaction has huge potential to improve drug discovery and production processes but has not been widely adopted in commercial processes due to the high levels of waste it produces.
In a paper published in the journal Science the reseachers have solved this problem and show their new process can be used towards the synthesis of the tuberculosis drug thiocarlide.
The Mitsonubu reaction has been well used in the Chemistry community since its discovery in 1967. The reaction is able to form a chemical bond between two molecules, an alcohol containing compound and a coupling partner of choice. These types of connections have a plethora of uses and are crucial in the synthesis of molecules used both in academic research and commercial applications. Whilst the Mitsonubu reaction is extremely useful it requires the addition of the two molecules you wanted to join together as well two additional reagents. The additional reagents are crucial for the reaction to work however are not incorporated into the final product. This results in the generation of a large amount of undesirable waste, causing problems both economically and environmentally.
This team’s innovative strategy involves adding a single additional reagent, a catalyst which is regenerated at the end of the reaction. The regeneration of the catalyst means that only a very small amount is needed to be added in order to activate many cycles of the reaction and it can be recovered when the process is complete. The main attraction of this method is to be able to recycle and reuse the catalyst, however another benefit is that the sole by-product is water, increasing the economic and environmental viability of the reaction.
The catalyst itself can be easily made on a large scale, and there are future plans to supply it to a wide range of industries to aid synthetic research.
‘This research represents an important step forward in the processing of chemicals in a greener and more sustainable way – even for those processes like Mitsunobu that have been used for a long time. We are now looking forward to taking developing this research further so that it can be used within the Pharmecuetical industry.”