Illustration of the Danish chemist Morten Meldal (born 1954). Meldal is best known for his development of click chemistry, highly reliable, selective reactions for the synthesis of new compounds that produce no, or minimal, by-products. He discovered the first 'click reaction', a copper-catalyzed azide-alkyne cycloaddition (CuACC) reaction, simultaneously with, but independently of, Karl Barry Sharpless. Meldal was awarded a share of the 2022 Nobel Prize in Chemistry along with Sharpless and Carolyn Bertozzi.