Visible-light photoredox-catalyzed fragmentation of methyl N-phthalimidoyl oxalate allows the direct construction of a 1,4-dicarbonyl structural motif by a conjugate addition of the methoxycarbonyl radical to reactive Michael acceptors. The regioselectivity of the addition of this alkoxyacyl radical species to electron-deficient olefins is heavily influenced by the electronic nature of the acceptor, behavior similar to that exhibited by nucleophilic alkyl radicals.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892945PMC
http://dx.doi.org/10.1021/acs.orglett.6b00895DOI Listing

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