77411-97-3Relevant academic research and scientific papers
Direct Allylic C(sp3)-H Thiolation with Disulfides via Visible Light Photoredox Catalysis
Hong, Soon Hyeok,Kang, Byungjoon,Kim, Jungwon
, p. 6013 - 6022 (2020/07/03)
In spite of the wide utility of allyl thioethers, the direct catalytic allylic C(sp3)-H thiolation remains elusive. Herein, we report the direct allylic C(sp3)-H thiolation mediated by visible light photoredox catalysis. The use of in situ-generated thiyl radical from disulfide as a hydrogen atom transfer (HAT) reagent and a coupling partner enabled selective cleavage of the allylic C(sp3)-H bond followed by C(sp3)-S bond formation. The undesired hydrothiolation, a prevalent reaction from facile thiyl radical addition to olefins, was prevented by the immediate deprotonation of thiol under basic conditions. A wide range of diaryl disulfides and olefins participated in the reaction, producing allyl thioethers with high efficiency. Mechanistic investigations revealed the participation of the photocatalyst as a redox mediator, which was crucial for the transformation of the allyl radical into the allyl cation and further ionic coupling process. Based on the proposed mechanism, a limitation in the synthesis of alkyl allyl sulfide was solved with a rationally designed more reducible unsymmetrical disulfide, which makes the desired catalytic cycle operative.
The Formation of Allyl Sulphides by Phenylthio-migration: Control by Silicon
Fleming, Ian,Paterson, Ian,Pearce, Andrew
, p. 256 - 262 (2007/10/02)
When γ-silyl-β-phenylthio-alcohols are treated with acid, the strategically placed silyl group encourages the rearrangement of the phenylthio-group, both from a secondary migration origin to a secondary migration terminus, and from a secondary migration origin to a tertiary migration terminus (4)->(6).Geraniol/nerol (12) and linalool (14) have been synthesised from a common intermediate (11) using this type of reaction.Phenylthio-migration from a tertiary migration origin (17)->(3) can be controlled to a limited extent by a suitably placed silyl group, but it is easier to achieve direct β-elimination of the silyl and phenylthio-groups (17)->(18).
