Massimo Sandal
Freelance journalist

According to a tradition, Aristotle stated that “Compounds do not react unless fluid or dissolved” (De Generatione). Modern medicinal chemistry still marches to the tune of the ancient Greek philosopher: 85% of chemicals used in pharma are solvents (1). This is hardly a sustainable approach. Organic solvents are expensive to process and dispose, and are hazardous polluters. Pharma generates enormous waste per kilogram of product (2,3). Clever processes employing “clean” solvents, from ethanol to supercritical CO2 , are booming. But what is greener and cheaper than giving up solvent completely?

Why mechanochemistry in the pharmaceutical industry?
Mechanochemistry is as old as history. Yet it has often been relegated to the sidelines in pharmaceutical chemistry, or even considered a nuisance: degrading APIs when preparing tablets, for example (4). To a “normal” organic chemist, mechanochemistry can indeed look pretty brutal: it doesn’t involve fine glassware but mortars, pestles, grinding jars. Mechanochemical synthesis however could reach Holy Grail-status in green chemistry: it requires little or no solvent. Mechanochemistry also pr ...