Organocatalyzed Domino Reactions to Access Diverse Glycohybrids

Abstract

Organocatalyzed domino (or cascade) reactions are one-pot, step-economical, multi-bond forming processes promoted by small organic molecules, usually amines, amino acids, thioureas, alkaloids, etc. These metal-free reactions are powerful and have special importance in glycoscience as they rapidly increase molecular complexity from carbohydrate-derived building blocks and enable stereoselective functionalization of densely oxygenated sugar scaffolds. These reactions precisely control the stereo- and regio-selectivity by participating actively during the course of the reaction. Further, they avoid metal contamination, crucial for biological and pharmaceutical applications, and offer step-economical access to glycomimetics and glycoconjugates. The excellent C-C bond forming ability and incorporation of new stereocentres in final products have been widely explored in the recent years. Herein, advances in the organocatalyzed domino reactions in glycoscience is covered. The examples clearly demonstrate the growing scope of organocatalytic cascade approaches to access a wide range of glycohybrid frameworks, including complex chiral architectures that are often difficult to obtain through conventional stepwise synthesis. The compatibility of these reactions with various functional groups, along with their ability to generate molecular diversity rapidly, highlights the importance of these reactions in synthetic organic chemistry.