Executive Summary : | Synthetic chemists are constantly striving to develop robust, environmentally friendly, atom-economic, and chemoselective transformations using readily available feedstock. However, the challenge lies in the use of suitable aryl radical precursors in arylative cross-couplings, cascade annulations, and direct C-H arylations of heterocycles for late-stage modification of drug-leads. This is particularly relevant given the prevalence of substituted aryl moieties in pharmaceuticals, biologically active compounds, agrochemicals, and functional materials. Despite their existence, the lack of mild conditions for aryl radical generation hampers their utility in organic synthesis. Recently, aryl radicals have been used in arylation reactions, but their applicability is limited due to instability and potential hazards. Diaryliodonium reagents (DIARs), a type of hypervalent iodine(III) reagent, have emerged as a non-toxic, cheap, and bench-stable alternative to aryl radical precursors. DIARs have been used as electrophiles in carbon-carbon and carbon-heteroatom bond-forming reactions under metal-free conditions and in transition metal-catalyzed transformations. However, their use as an aryl transfer reagent under photoinduced conditions is underexplored. The investigator aims to develop novel photoinduced reaction technologies using a range of organic and metallic photocatalysts to unleash the full potential of DIARs towards the generation of various aryl radicals through innovative pathways. The generated structurally and electronically diverse aryl radicals will participate in various cascade annulations and direct arylations for the synthesis and late-stage functionalization of heterocycles and carbocycles. |