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Acyl Azolium-Photoredox-Enabled Synthesis of β-Keto Sulfides.

ABSTRACT: α-Heteroatom functionalization is a key strategy for C-C bond formation in organic synthesis, as exemplified by the addition of a nucleophile to electrophilic functional groups, such as iminium ions; oxocarbenium ions; and their sulfur analogues, sulfenium ions. We envisioned a photoredox-enabled radical Pummerer-type reaction realized through the single-electron oxidation of a sulfide. Following this oxidative event, α-deprotonation would afford α-thio radicals that participate in radical-radical coupling reactions with azolium-bound ketyl radicals, thereby accessing a commonly proposed mechanistic intermediate of the radical-radical coupling en route to functionalized additive Pummerer products. This system provides a complementary synthetic approach to highly functionalized sulfurous products, including modification of methionine residues in peptides, and beckons further exploration in C-C bond formations previously limited in the standard two-electron process.

SUBMITTER: Rourke MJ

PROVIDER: S-EPMC10651059 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Acyl Azolium-Photoredox-Enabled Synthesis of β-Keto Sulfides.

Rourke Michael J MJ Wang Charles T CT Schull Cullen R CR Scheidt Karl A KA

ACS catalysis 20230530 12

α-Heteroatom functionalization is a key strategy for C-C bond formation in organic synthesis, as exemplified by the addition of a nucleophile to electrophilic functional groups, such as iminium ions; oxocarbenium ions; and their sulfur analogues, sulfenium ions. We envisioned a photoredox-enabled radical Pummerer-type reaction realized through the single-electron oxidation of a sulfide. Following this oxidative event, α-deprotonation would afford α-thio radicals that partici ...[more]

PMID: 37969469

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