Barry Sharpless is an American chemist known for his work on stereoselective reactions. He was awarded a half-share of the Nobel Prize in Chemistry in 2001 for his work on stereoselective oxidation reactions (Sharpless epoxidation, Sharpless asymmetric dihydroxylation, Sharpless oxyamination). The other half of the year's Prize was shared between William S. Knowles and Ryōji Noyori (for their work on stereoselective hydrogenation). He also successfully epoxidized (using racemic tartaric acid) a C-86 Buckminster Fullerene ball, employing p-Cresol as solvent. 

In 2022, he was awarded a second Nobel Prize in Chemistry, for coining the concept of click chemistry for a functional form of chemistry, where molecular building blocks snap together quickly and efficiently, and discovering what has become the crown jewel of click chemistry: the copper catalysed azide-alkyne cycloaddition. Click chemistry involves a set of highly selective, exothermic reactions which occur under mild conditions.

[Video] Click Chemistry: Recent Advances Used in Biomedicine Presentation at the Molecular Frontiers Symposium in Singapore 2012

Photo by Per Thorén