Solvents make a large contribution to the environmental impact of manufacturing processes of active pharmaceutical ingredients (API), as well as playing an important role in other chemical industries, with millions of tons used and disposed of each year. GlaxoSmithKline (GSK) has previously reported on the both the development of a GSK solvent selection guide and the incorporation of solvent life cycle inventory and assessment information. The GSK solvent selection guide has been further enhanced by: • Revising the assessments of factors that impact process safety, separating reactivity from fire and explosion rankings. • More than doubling the number of solvents in the guide, to a total of 110 from the initial 47. • Adding a customised solvent selection guide appropriate for medicinal chemistry and analytical laboratories. The new GSK solvent selection guide enables GSK scientists to objectively assess solvents and determine whether existing or new solvents brought to market as ‘greener’ alternatives truly represent a more sustainable choice or whether they are just addressing a single issue associated with sustainability.

Dihydrolevoglucosenone (Cyrene) is a bio-based molecule, derived in two simple steps from cellulose, which demonstrates significant promise as a dipolar aprotic solvent.

A review of the solvent effects that control the productivity of cross-coupling reactions, and suggested safer alternative solvents.

The global bio-based chemical market is growing in size and importance. Bio-based solvents such as glycerol and 2-methyltetrahydrofuran are often discussed as important introductions to the conventional repertoire of solvents. However adoption of new innovations by industry is typically slow. Therefore it might be anticipated that neoteric solvent systems (e.g., ionic liquids) will remain niche, while renewable routes to historically established solvents will continue to grow in importance. This review discusses bio-based solvents from the perspective of their production, identifying suitable feedstocks, platform molecules, and relevant product streams for the sustainable manufacturing of conventional solvents.