An acyl iminium ion-initiated tandem cyclization gave an unexpected dienone product, a seco-azasteroid (2). The factors governing the formation of 2 were investigated in an attempt to optimize its formation. The reaction was applied to a more elaborate system, resulting in the synthesis of the full steroid skeleton of 13-azaandrosta-1,4-diene-3,17-dione (3), which contains the unusual substitution of a chlorine atom for the axial 19-methyl.
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Article Synopsis
- * The study introduces a new method for radical reactions using photoredox techniques which enhances the Pummerer-type reaction through single-electron oxidation of sulfides to create reactive thio radicals.
- * This innovative approach opens up new possibilities for creating highly functionalized sulfur compounds, such as modifying methionine in peptides, and could revolutionize C-C bond formation that was previously limited by traditional methods.
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