PRACTICAL SYNTHESES OF ALLYLSILANES FROM 1-BENZENESULFONYL-2-TRIMETHYLSILYLETHANE
The methanesulfonates of the adducts of aldehydes and ketones with 1-(1-benzenesulfonyl-2-trimethylsilyl)ethyllithium are converted by sodium-amalgam to allylsilanes.
2-(3-Cyanopropyldimethylsilyl)ethyl as a Polar Sulfur Protecting Group
Organosulfur compounds are ubiquitous in synthetic chemistry, biology and materials chemistry. The reactivity of free sulfhydryls requires their masking in many synthetic strategies. To facilitate the isolation of protected thiols by chromatography, we propose 2-(3-cyanopropyldimethylsilyl)ethyl as a polar protecting group analogue of 2-(trimethylsilyl)ethyl. The masked thiophenol is obtained in two synthetically complementing ways. Either an existing thiophenol is protected, or the protected thiol group is introduced by a cross-coupling reaction. In both cases the required reagents are readily available from inexpensive starting materials. Thiol protection and thiol introduction both tolerate a large variety of functional groups and substitution patterns, and the protected thiophenols are stable toward a broad range of reaction conditions. The stability of the protected derivatives in cross-coupling reactions and the mild reaction conditions for the release of the protecting group further emphasizes the potential of the methodology.
Bannwart, Linda M.,Mayor, Marcel,Rieder, Pascal S.
p. 4153 - 4164
(2019/11/14)
Bu2SnIH-promoted proximal bond cleavage of methylenecyclopropanes and successive radical cyclization and/or Pd-catalyzed coupling reaction
The unprecedented regioselective hydrostannation of methylenecyclopropanes to give vinyltins was achieved using dibutyliodotin hydride (Bu2SnIH), which could be applied to intramolecular radical cyclization. Copyright
Treatment of trimethylsilylethanes bearing α-phenyl groups and β-phenylthio, phenylsulfonyl or cyano groups with LDA causes elimination-rearrangement mediated by the β-carbanionic species. Mechanistic conclusions are based on isotopic labelling experiment
Menichetti, Stefano,Stirling, Charles J. M.
p. 1511 - 1515
(2007/10/03)
Synthesis of Enantiomerically Pure -CoA: The Causative Agent of Jamaican Vomiting Sickness