18740-08-4Relevant academic research and scientific papers
Regio- and enantioselective iridium-catalyzed allylation of thiophenol: Synthesis of enantiopure allyl phenyl sulfides
Zheng, Shengcai,Gao, Ning,Liu, Wei,Liu, Dongge,Zhao, Xiaoming,Cohen, Theodore
scheme or table, p. 4454 - 4457 (2010/11/19)
A highly regio- and enantioselective allylic alkylation of sodium thiophenoxide has been realized by [Ir(COD)Cl]2/phosphoramidite along with CsF as an additive, producing highly enantioenriched allyl phenyl sulfide compounds with up to 99% ee.
Fast ruthenium-catalysed allylation of thiols by using allyl alcohols as substrates
Zaitsev, Alexey B.,Caldwell, Helen F.,Pregosin, Paul S.,Veiros, Luis F.
experimental part, p. 6468 - 6477 (2010/02/28)
The allylation of aromatic and aliphatic thiols, by using allyl alcohols as substrates, requires only minutes at ambient temperature with either a Ru Iv catalyst, [Ru(Cp*)(n3CH5)(CH 3CN)2](PF6)2 (2; Cp* = pentamethylcyclopentadienyl) or a combination of [Ru(Cp*)(CH 3CN)3](PF6) and camphor sulfonic acid. Quantitative conversion is normal and the catalyst possesses high functional-group tolerance. The use of [Ru(Cp*)(CH3CN) 3](PF6) alone affords poor results. A comparison is made to the results from catalytic runs based on the use of carbonates rather than alcohols, by using 2 as the catalyst, and it is shown that the products from the alcohols are formed faster, so there is no advantage in using a carbonate substrate. The observed branched-to-linear (b/1) ratios when using substituted alcohols decrease with time suggesting that the catalysts isomerise the products. A new methodology from which one can select the desired isomeric product is proposed. DFT calculations and NMR spectroscopic measurements, by using an arene sulfonic acid as co-catalyst, suggest that 6-complexes are not relevant for the catalytic system. Moreover, the DFT results indicate that l)any rf-complexes from the acids RC6H4SO 3H result from deprotonation of the acid, 2) complexation of the thiol, via the deprotonated sulfur atom, is preferred over complexation of the O atom of the sulfonate, RC6H4SO3and 3) a sulfonate O-atom complex will be difficult to detect.
Cleavage of Co-C bond in allyl cobaloximes with arenesulphenyl chloride
Gupta,Dixit,Singh,Kanth
, p. 830 - 834 (2007/10/03)
Arenesulphenyl chlorides (ArSCl; Ar = Ph, C6Cl5, 2,4(NO2)2 C6H3) are reacted with allylcobaloximes, RCo(dmgH)2Py (R= allyl), under thermal and photochemical conditions to obtain the corresponding sulphides as the major organic products. α-Pinenyl cobaloxime forms the ring opened product as well. The homolytic as well as heterolytic cleavage of the Co-C bond is considered.
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).
PHENYLSELENODESILYLATION OF ALLYLSILANES AND REGIOSPECIFIC TRANSFORMATION OF ALLYLSILANES TO ALLYLIC ALCOHOLS VIA ALLYLSELENIDES
Nishiyama, Hisao,Itagaki, Kazuyoshi,Sakuta, Koji,Itoh, Kenji
, p. 5285 - 5288 (2007/10/02)
Allylsilanes were converted regiospecifically to allylselenides by reaction with phenylselenenyl chloride and subsequent treatment with anhydrous tin(II)chloride or florisil.Oxidative work-up of these allylselenides gave the corresponding allylic alcohols regiospecifically.
