organosynthesis

Organosynthesis is the branch of chemistry concerned with the design and execution of chemical routes that construct organic molecules. It encompasses the synthesis of small molecules, natural products, pharmaceuticals, agrochemicals, and advanced materials. Core tasks include the formation of carbon–carbon and heteroatom–carbon bonds, as well as ring formation and functional-group interconversions.

Synthetic methods rely on catalysis and activation strategies to improve efficiency and selectivity. Common approaches include cross-coupling reactions (such as Suzuki–Miyaura, Heck, and related palladium- or nickel-catalyzed couplings), nucleophilic additions, condensations, cycloadditions, and C–H activation. Organocatalysts (amines, thioureas, phosphoric acids) and transition-metal catalysts enable enantioselective and diastereoselective synthesis. Photoredox catalysis, flow chemistry, and enzymatic catalysis are increasingly important for sustainability.

History: Early organic synthesis relied on classical transformations discovered in the 19th and 20th centuries. The modern field expanded with metal-catalyzed cross-coupling in the late 20th century and the rise of organocatalysis and biocatalysis in the early 21st century, driving more efficient and selective routes with milder conditions and lower waste.

Applications and challenges: Organosynthesis underpins drug development, polymer science, and materials chemistry. Its goals include high yield, selectivity, scalability, and reduced environmental impact. Ongoing challenges involve stereocontrol, functional-group compatibility, and scaling laboratory methods to industrial production, with increasing use of computer-assisted retrosynthesis and sustainable reaction design.