n‐Butanol: an ecologically and economically viable extraction solvent for isolating polar products from aqueous solutions

Water is the solvent of choice in terms of greenness and sustainability. However, it can be difficult to isolate very polar products from water. Here, we discuss the use of n -butanol as a solvent to extract polar compounds from aqueous solution. n -Butanol produces high yields and can also be sourced sustainably from biomass, which makes it attractive from a climate perspective. The reason for its high efficiency is that the wet n-butanol phase is a nanomaterial that incorporates little pockets of water that can stabilize the polar solute. Thus, the environment remains very water-like, and the presence of hydrophobic groups can tip the transfer reaction towards the n -butanol phase. We also discuss a simple estimate whether n -butanol will be an efficient extraction solvent for the compound of interest based on common public databases. This should help to guide practicing organic chemists during the solvent selection process.