Schotten-Baumann reaction RXNO RXNO:0000165 The coupling of an alcohol or amine with an acyl chloride to give an ester or amide. A two-phase solvent system is often used, to enable the acid generated during the reaction to be neutralised by the aqueous base, while the starting materials and products remain in the organic phase. https://www.rsc.org/Merck-Index/reaction/r392/ substitution step