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Upstream product

• 21889-88-3 hept-6-en-2-one 
• 882-33-7 diphenyldisulfane 
• 477482-18-1 3-methyl-6-(phenylthio)hex-1-en-3-ol 

Relevant academic research and scientific papers

Cyclization by intramolecular carbolithiation of alkyl- and vinyllithiums prepared by the action of aromatic radical anions on phenyl thioethers. High stereoselectivity in the cyclization accelerated by an allylic lithium oxyanion

The reductive lithiation of alkyl and vinyl phenyl thioethers by aromatic radical anions is shown to be the most general method yet known for preparing organolithiums capable of intramolecular carbometalation of unactivated alkenes to produce five-membered rings and in one case a four-membered ring (in a far higher yield than known cases). The relative rates of cyclization for alkyllithiums are secondary > tertiary > primary, and the yields are very high. In the secondary case, the stereoselectivity is extremely high, producing a cyclopentylmethyllithium with a trans-2-alkyl substituent. A remarkable finding is that for all of the organolithiums a lithium oxyanionic group in the proximal allylic position to the alkene greatly accelerates the cyclization and leads almost exclusively to a trans relationship between the CH2Li group and the OLi group, the opposite relationship from that observed in intramolecular carbolithiations by allyllithiums. A mechanistic rationale for this divergence is discussed. One of the two types of proximal homoallylic lithium oxyanions exerts an analogous effect. An intriguing limitation, even occurring with the highly reactive secondary organolithium and in the presence of an allylic oxyanionic group, is the failure of intramolecular carbolithiation when a methyl group is at the terminus of the alkene.

Cyclization by intramolecular carbolithiation of alkyl- and vinyllithiums prepared by reductive lithiation: Surprising stereochemistry in the lithium oxyanion accelerated cyclization

The versatility of intramolecular carbolithiation of simple alkenes to yield cyclopentylmethyllithiums by unconjugated organolithiums is greatly increased (1) by generating the organolithiums by reductive lithiation of phenyl thioethers with aromatic radi

Intramolecular ketyl-olefin cyclization mediated by magnesium metal

Ketones tethered to carbon-carbon multiple bonds at δ-position are treated with magnesium metal to provide cyclized products which stem from addition of ketyl radical to olefinic or acetylenic bonds.

Samarium(II) Iodide-Induced Reductive Cyclization of Unactivated Olefinic Ketones. Sequential Radical Cyclization/Intermolecular Nucleophilic Addition and Substitution Reactions

Samarium(II) iodide in the presence of HMPA effectively promotes the intramolecular coupling of unactivated olefinic ketones by a reductive ketyl-olefin radical-cyclization process.The reaction is quite general for the formation of 5- and 6-membered carbocycles and even provides modest yields in less facile cyclization processes as evidenced by the generation of methylcyclooctanol via an 8-endo cyclization.Sequential radical cyclization-intermolecular nucleophilic addition/substitution processes set the SmI2 reaction apart from its radical-chain, photochemical, and electrochemical counterparts.In addition to delineating the synthetic potential of this reaction, the role played by HMPA in enhancing SmI2 reactivity has been further refined, and a model correlating the high diastereoselectivity and product distribution in SmI2-promoted reductive coupling processes with HMPA concentration has been established.