129218-81-1Relevant articles and documents
Theoretical and experimental analyses of the deprotonation of thiirane S-oxides: The stereoselective formation of trans-alkyl- and gem-silylethenesulfenate anions
Refvik, Mitchell D.,Froese, Robert D. J.,Goddard, John D.,Pham, Hung H.,Pippert, Mark F.,Schwan, Adrian L.
, p. 184 - 192 (1995)
Experimental and theoretical studies of the regioselective deprotonation of thiirane S-oxides are reported. Experimentally under the reaction conditions of LiHMDS/THF/-78°C with anti-alkylthiirane S-oxides or anti-silylthiirane S-oxides as starting materials, the products of ring-opening are (E)-2-alkylethenesulfenate and 1-silylethenesulfenate anions, respectively. Experiments involving deuterium labeling clearly indicate that a regioselective deprotonation reaction was followed by a stereoselective ring-opening. Ab initio methods at both the Hartree-Fock and M?ller-Plesset perturbation theory levels with the 6-31+G(d) basis set were used to examine both lithiated methyl- and silylthiirane S-oxides. Of the possible anti-substituted species, the coordination of the lithium anti to the methyl and gem to the silyl is predicted to be the most stable. These stable intermediates with the lithium syn to the sulfoxide could ring-open to yield the experimentally observed products.
REACTIONS OF EPISULPHOXIDES AND EPISULPHIDES WITH ORGANOLITHIUM REAGENTS
Bonini, Bianca F.,Maccagnani, Gaetano,Mazzanti, Germana,Zani, Paolo
, p. 115 - 121 (2007/10/02)
Reactions of aryl-substituted episulphoxides and episulphides with butyl- and phenyllithium, lithium di-isopropyl amide and lithium dimethylcuprate have been examined.The following reaction paths could be observed: a) attack at sulphur leading to olefins with complete retention of configuration at the carbon skeleton; b) attack at proton leading to a vinyl sulphenate in the case of episulphoxides, or to a thiolate anion, in the case of episulphides, trapped as methyl vinyl sulphoxide or methyl vinyl sulphide, respectively; c) attack at carbon, observed only in thereaction of styrene episulphoxide with lithium dimethylcuprate, leading to a saturated sulphenate anion trapped as alkyl methyl sulphoxide.Mechanisms and stereochemistry of these processes are discussed.
