Nucleophilic Addition of Lithiated Phenyl Trimethylsilylmethyl Sulfide to Activated Olefins. A Facile Synthesis of 2-(Functionally) Substituted Silylcyclopropanes
作者:Ernst Schaumann、Carsten Friese、Carsten Spanka
DOI:10.1055/s-1986-31864
日期:——
The lithio derivative of phenyl trimethylsilylmethyl sulfide undergoes smooth addition to activated ethylene derivatives to afford trimethylsilylcyclopropanes, except for the addition to methyl 2-phenylpropenoate which leads to the formation of methyl 4-trimethylsilyl-2-phenyl-4-(phenylthio)butanoate.
Copper-Catalyzed Extended Pummerer Reactions of Ketene Dithioacetal Monoxides with Alkynyl Sulfides and Ynamides with an Accompanying Oxygen Rearrangement
and ynamides provided a wide variety of γ,γ‐disulfanyl‐β,γ‐unsaturated carbonyl compounds with an accompanying oxygen rearrangement. The products can be easily converted into 1,4‐dicarbonyl compounds and substituted heteroaromatics. DFT calculations and mechanistic experiments revealed a new interesting stepwise addition/oxygen rearrangement mechanism.
Interrupted Oligomerization Revisited: Simple and Efficient One-Pot Multicomponent Approach to Versatile Synthetic Intermediates
作者:Roman A. Valiulin、Logan M. Halliburton、Andrei G. Kutateladze
DOI:10.1021/ol701847b
日期:2007.9.1
multicomponent reaction allowing for a one-pot formation of three carbon-carbon bonds has been developed. It is based on in situ generation and anionic dimerization of methylenedithiane and produces a versatilesynthetic equivalent of 4-hydroxy-1,3-alkanediones which, among other things, offers expeditious one-pot access to 3(2H)-furanones.
A Novel Synthesis of<i>syn</i>and<i>anti</i>β-Hydroxy Dithioacetals, Masked Cross-Aldols between Aldehydes
作者:Terunobu Saitoh、Naohisa Jimbo、Junji Ichikawa
DOI:10.1246/cl.2004.1032
日期:2004.8
Ketene dithioacetals readily reacted with aldehydes in the presence of a Lewis acid such as BF 3 .OEt 2 or TMSOTI to generate the cationic adducts, which in turn reacted with NaAlH 2 -(OCH 2 CH 2 OCH 3 ) 2 , leading to the corresponding β-hydroxy dithioacetals, masked cross-aldols between aldehydes. Each diastereomer was selectively obtained by choosing the appropriate Lewis acid and substituents on
Intramolecular Diels-Alder reactions of vinylboranes. A highly stereoselective two-step decalin synthesis
作者:Daniel A Singleton、Yu-Kai Lee
DOI:10.1016/0040-4039(95)00568-w
日期:1995.5
1,7,9-Decatrienylboranes, generated in situ from either hydroboration of 5 or boron-tin exchange with 6, undergo very highly stereoselective intramolecular Diels-Alderreactions.