Research Projects

Science is being upgrading with lot of innovative concepts day-by-day. One of such innovative concepts is “click chemistry” which was first introduced in 2001 by K. B. Sharpless; it deals with a class of chemical reactions which are modular, wide in scope, biocompatible, insensitive to oxygen or water, simple to perform, stereospecific (not essentially enantiospecific), high yielding, obey the 12 principles of green chemistry by generating the harmless by-products and utilizes readily available starting materials. After this discovery, many scientists all over the world started using this concept for the synthesis of various medicinally important molecules. Despite of numerous applications, these click reactions are restricted to either terminal alkynes under metal catalysis or strain promoted alkynes. In this context, in 2008, our research group first discovered the proline catalyzed synthesis of NH-1,2,3-triazoles from cylohexenones and azides under biocompatible conditions as a green alternative to metal based click reactions. Motivated by this work, later in 2011, Wang and co-workers, Bressy and co-workers demonstrated the preparation of 1,4,5-trisubstited 1,2,3-triazoles in good to excellent yields respectively, in the presence of organocatalysts. Our continuous efforts in this area led to an elegant and efficient approaches for the high yielding synthesis of 1,4-disubstituted and 1,4,5-trisubstituted 1,2,3-triazoles through an enolate-mediated organocatalytic azide-carbonyl [3+2]-cycloaddition (OrgACC) reactions. Indeed, these metal-free click reactions provide a solution to minimize the metal residues in the 1,2,3-triazole products, offers wide scope and utilize relatively cheap or easily accessible carbonyl compounds as azide reacting partners (dipolarophiles). Consequently, the OrgACC’s evolved as an appealing strategy for pharmaceutical and biomedical applications. But till date, there is no protocol or methodology available for the synthesis of atroposelective 1,2,3-triazoles using asymmetric organocatalysis. The synthesis and application of biocompatible and pharmaceutically interesting 1,2,3-triazoles containing atropoisomeric scaffolds are rarely studied because of the absence of efficient synthetic protocols and also due to the low conformational stability of the products. The lack of green, efficient and metal-free approaches for the synthesis of axially chiral 1,2,3-triazoles and the increasing demand for single enantiomer drugs featuring chiral axis in pharmaceutical industry and modern drug discovery is encouraging us to focus on design and development of asymmetric variant of OrgACC click chemistry. Thus, we are very much interested in the development of atropeselective methodologies toward the synthesis of natural product-like and pharmaceutically privileged scaffolds.