Executive Summary : | Tandem catalysis is a promising method for replacing hazardous and waste-generating methods in modern science. It can be performed in one-pot, single-step processes, reducing time, energy, and waste production. However, the complexity of this process requires careful planning and selection of ideal reaction parameters. The substitution of expensive and toxic C-C and C-N bond-forming reagents with inexpensive, renewable, and bench-stable alcohols can enhance the synthetic value of the protocol. To successfully carry out the proposed tandem catalysis, a variety of homogeneous and heterogeneous catalysts are proposed. For homogeneous systems, proton responsive units and/or carbene fragments are incorporated in the ligand platform, as metal complexes bearing these fragments display better reactivity in alcohol dehydrogenation. Various multicomponent tandem methodologies are proposed for the transformation of small molecules like acetonitrile, aldehyde, ketone, amine, azide, nitro, nitrile, etc. to more complex compounds. These methodologies will have a significant impact on organic synthesis and have not yet been reported in the literature. Tandem synthesis of functionalized nitriles/amines/amides directly from acetonitrile is also explored. Tandem dehydrogenative functionalization of saturated N-heterocycles is also explored. The direct access to asymmetric tertiary amines from aldehydes/ketones and amines is also explored. Reductive functionalization of α, β-unsaturated ketones is also proposed, with tandem transfer hydrogenation followed by alkylation of α, β-unsaturated ketones using alcohol being explored. |