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Updated: Aug 24, 2026

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Published on: September 28, 2022
Carbon-carbon bond-forming reaction of cyclic sulfonium ylides stabilized by a carbonyl group
1Department of Chemistry and Materials Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-8585, Japan.
Abstract:
Rhodium(II)-catalyzed decomposition of diazoketones 1 and 5 bearing a cyclic dithioacetal, in the presence of aldehyde and ClTi(Oi-Pr)(3), afforded both or one of the C=C-bonded products, i.e., ring-enlarged enone 2 and ring-transformed thiophenone 3, that were formed between aldehyde and intermediate bicyclosulfonium ylide. The stereochemistry of the exocyclic C=C bond in the products was exclusively Z. The sulfonium atom that transiently composed the ylide was incorporated into products, but no oxirane was formed.
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