Eco-efficiency and scalable synthesis of bisamides in deep eutectic solvent

Solvents define a major part of the environmental performance of processes in chemical industry and also impact on cost, safety and health issues. In order to minimize the environmental impact resulting from the use of volatile organic solvents in chemical production, a deep eutectic solvent (DES) consisting of choline chloride and urea (1:2 molar ratio) was prepared and used as the co-solvent for the preparation of gem-bisamides starting from aldehydes. The deep eutectic solvent fulfills the triple role of being a solvent, as a catalyst and as reagents, and provides a green, safe and cost-effective access to various gem-bisamides without a tedious work-up. The desired compounds were obtained in a few mm (15-120 min) with moderate to good yields (52-90%) and amenable to large scale production without significant loss in its efficiency. (C) 2015 Elsevier B.V. All rights reserved.