Research and Development of Domino Radical Cyclization Reactions

This article highlights our recent studies on radical chemistry using the domino reactions constructing the carbon-carbon and carbon-heteroatom bonds. Stereocontrol in domino radical addition-cyclization-trapping reactions was achieved by new approach, which contains hydroxamate ester moiety as a chiral Lewis acid-coordinating tether between two radical acceptors. The polarity-mismatched perfluoroalkyl radical addition was next studied. The domino reaction with perfluoroallcyl radicals proceeded via the unfavorable polarity-mismatched addition of electrophilic radicals to electron-deficient acceptors. The photo-induced domino reactions were also studied in aqueous media. The photocatalyst, Ru(bpy)(3)C-12 center dot 6H(2)O, has the potential to induce the carbon-carbon bond-forming reactions in aqueous media. In the presence of water, the photoinduced electron transfer (PIET) from the excited singlet state of rhodamine B smoothly proceeded and promoted domino reactions.