Cascade radical reactions via the formation of carbon-carbon/heteroatom bondsAuthor(s): Timothy Wilson
To build radical chemistry-based cascade events for forming carbon-carbon and carbon heteroatom bonds. The radical and anionic carbon-carbon bond-forming procedure produced,-disubstituted amino acids via the diethylzinc-promoted reaction of dehydroamino acid derivatives with acid anhydride or-allyl palladium complex. Using Bu3SnH and Pd (PPh3)4, this reaction was effectively developed into the reductive transformation of N-phthaloyl dehydroalanine. Using hydroxamate ester functionality as a chiral Lewis acid-coordinating tether between two radical acceptors, the chiral Lewis acid-mediated cascade radical addition-cyclization-trapping reaction went smoothly with good enantioselectivities. This approach was used in a cascade reaction involving the addition of electrophilic perfluoroalkyl radicals to electron-deficient acceptors with adverse polarity mismatch. In addition, a cascade sequence was observed that was terminated by radical-radical coupling. Cascade process strategies have the benefit of forming many carbon-carbon and/or carbon-heteroatom bonds in a single operation.