Executive Summary : | Photoredox catalysis uses light energy to catalyze organic reactions, revolutionizing synthetic organic chemistry by achieving difficult and strenuous transformations under mild conditions. Nickel catalysis, on the other hand, has played a significant role in achieving C(sp2)-C(sp3) & C(sp3)-C(sp3) cross-coupling reactions elegantly due to its facile oxidative addition step and less β-hydride elimination. When combined with photoredox catalysis, it can achieve more interesting transformations. Carbodifunctionalization of alkenes and alkynes has attracted many synthetic chemists as it allows access to densely functionalized carbon skeletons in a single step. Traditional two-electron strategies using transition metal catalysis often suffer from disadvantages such as higher temperature, use of sensitive organometallic reagent, and expensive catalysts. Recently, few research groups have adopted a dual nickel-photoredox catalytic system for carbodifunctionalization of alkenes and alkynes due to the mild reaction conditions and facile C(sp2)-C(sp3) coupling under these conditions. This proposal proposes a more challenging multicomponent radical cascade addition-cyclization-coupling strategy for carbodifunctionalization of 1,5-enynes (& 1,6-enynes) in a sequential sequence manner. This process can directly give access to densely functionalized carbocycles such as indanes and other heterocycles, opening up new chemical space and reactivity patterns for synthetic chemists. The proposal aims to achieve four main objectives: multicomponent acylative cyclization of 1,5-enynes, multicomponent sulfonylative cyclization of 1,5-enynes, multicomponent acylative arylation of 1,5-enynes using a dual Ni-photoredox catalysis, and multicomponent synthesis of heterocycles from 1,6-enynes. |