Work into solvents that can switch polarity from an ionic to non-ionic form, negating the need to remove them after each step, has won a researcher the John C Polanyi Award.
The researchers have worked on a range of reactions, whereby the solvents polarity is switched by a trigger, such carbon dioxide, and then changed back by the presence of a different substance.
A switchable solvent can be given different properties enabling it to be used in multiple reaction and separation steps. This reduces the cost and environmental impact as the solvent does not have to be removed at each stage of production.
The solvents are not yet capable of performing multi-step reactions, which would give the technology many applications in the pharmaceutical industry. However, Philip Jessop, the recipient of the award, believes it can be achieved.
Speaking to in-PharmaTechnologist Jessop said: “I suspect that the first commercial applications for the switchable solvents will not be in multi-step synthetic procedures but rather in simpler separations processes such as extraction-flitration-precipitation processes that also include solvent recycle.
“As we produce improved switchable solvents with a greater range of chemical compatibility (or a range of switchable solvents with different chemical compatibilities), then the application to multi-step syntheses will become more promising.”
Jessop explained that he and his research group at Queen’s University in Canada will now be working to create different kinds of switchable solvents, for instance those that change volatility or acidity.
In addition they will be optimising solvents for particular reactions, bringing the possibility of niche, commercialised reactions a step closer.