Industrial collaboration adds to thymol

A cleaner way to make thymol, a perfume, disinfectant and medicinal molecule, has been developed by chemists in the UK and Switzerland. Thymol is also used as an intermediate in menthol manufacture.

A continuous synthetic process in supercritical carbon dioxide was devised by Martyn Poliakoff and colleagues at the University of Nottingham in conjunction with Thomas Swan & Co. and Swiss company Schenectady Pratteln.

The process is a great improvement on the traditional manufacturing method, which creates waste and involves hazardous chemicals.

Poliakoff’s technique involves correlating gas chromatograms to investigate how products are formed during the reaction. With their deeper understanding of the process, researchers could then find more environmentally friendly catalysts.

Solid resins with acid groups are often used in these reactions but in this case gamma-alumina was found to be a much better catalyst.

The supercritical carbon dioxide was also shown to have an important role in suppressing the formation of minor products, and so improving the selectivity of the reaction.

’I see good opportunities to extend this chemistry to other aromatic products and to incorporate such reactions into a more complicated sequence of reactions,’ said Poliakoff. He added that industrial implementation of organic reactions is an important goal in green chemistry and that his work exemplifies effective collaboration between industry and academia.

Niamh O’Connor