Research Projects

The design of new molecular architectures to give a promising catalyst free and developing novel methodologies that are economical (cost, atom and stepwise) and sustainable are the current interests. The synthesis of aza heterocyclic compounds remains significant interest in the area of synthetic organic chemistry. The iminoiodinane as nitrene is recognized as a versatile N1 synthon, which is highly reactive and commonly used to synthesize various nitrogen-containing building blocks. Considering the importance of N-heterocycles and unique reactivity of photoexcited triplet nitrene, the proposal aims to access nitrogen containing mono and bicyclic compounds through visible light promoted annulation of functionalized alkenes and polyenes using nitrene derived from iminoiodinanes. Nitrene transfer reactions with vinyl cycloalkane gives novel tetrahydroazepine derivatives with suitable conditions. Further extension of the proposed strategy with vinyl cyclopropane derived from indoline derivative is expected to offer potent nitrogen based spiro cyclic compounds (Scheme 1b). The tunable substituents of vinyl cyclopropane, vinyl cyclobutanes and iminoiodinanes extends the scope of the methodology. These new products will be an active intermediate for a wide range of applications in pharmaceuticals, agrochemicals, natural products, etc. Extend the reactivity of triplet nitrenes, the nitrene transfer radical cascade cyclisation has been envisaged for the synthesis of novel 3-aza bicyclic compounds under photochemical condition from non-conjugated dienes and iminoiodinanes. Due to the presence of two different alkenes in the molecule, potential regioselectivity issue is anticipated, which will be addressed through suitable choice of substituents to stabilize the intermediate radicals. Furthermore, use of alkene tethered vinyl cycloalkane under the visible light nitrene annulation conditions is expected to offer structurally different N-heterocycles. The conditions will be appropriated optimized to achieve the required chemo and regioselectivity. We further developed the method to synthesis novel aza bicyclo compounds will be explored employing donor-acceptor bicyclobutane and triplet nitrene intermediate generated from iminoiodinanes. This reaction would furnish the new aza bicyclo[1.1.1]pentane, which could potentially as bioisosters in drug discovery.