Carry out extractions more efficiently at elevated temperatures

19 March 2004

This is not a new idea, but is one that is often forgotten or overlooked. A specific example can be found in a recent paper in Organic Process Research and Development from Johnson and Johnson (2003, 7, 939).

During the work up of the piperazine alkylation shown, the product was extracted, after an aqueous quench, with toluene. The extraction yield at 25°C was only 40%, but at 70°C the extraction was complete.