Diastereoselectivity in the Diels-Alder reactions of thio aldehydes
作者:Edwin. Vedejs、J. S. Stults、R. G. Wilde
DOI:10.1021/ja00224a033
日期:1988.8
La reaction de Diels-Alder de thioaldehydes avec le cyclopentadiene produit preferentiellement l'isomere endo. La selectivite la plus elevee est obtenue avec les thioaldehydes RCHS ou R est un groupe alkyle encombrant tel que t-butyl ou isopropyl
La 反应 de Diels-Alder de thioaldehydes avec le cyclopentadiene produitpreferentiellement l'isomere end。La selectivite la plus elevee est obtenue avec les 硫醛 RCHS ou Rest un groupe 烷基化 tel que t-丁基 ou 异丙基
Sequential One-Pot Addition of Excess Aryl-Grignard Reagents and Electrophiles to<i>O</i>-Alkyl Thioformates
carried out in the presence of cyclopentadiene. As a result, hetero‐Diels–Alder adducts of the thioaldehyde and the diene were formed. The treatment of a mixture of the thioformate and phenyl Grignard reagent with iodine gave 1,2‐bis(phenylsulfanyl)‐1,2‐diphenyl ethane as a product, which indicated the formation of arylsulfanyl benzylic Grignard reagents in the reaction mixture. When electrophiles were
3,6‐Dihydro‐2H‐thiopyrans are important structural motifs both in organic synthesis and medicinal chemistry. A continuous flow‐process for the photochemical generation of thioaldehydes from phenacyl sulfides and the ensuing [4+2]‐cycloaddition with electron‐rich 1,3‐dienes was developed. The cycloadducts were obtained with excellent yields in short reaction times and much improved productivities as
Protiodesilylation of 3-trimethylsilyl-2-thiabicyclo[2.2.1]hept-5-enes and derivatives: a stereochemical study
作者:Bianca F. Bonini、Enza Masi、Stefano Masiero、Germana Mazzanti、Paolo Zani
DOI:10.1016/0040-4020(96)00032-4
日期:1996.3
endo- and exo-trimethylsilyl-3-phenyl-2-thiabicyclo[2.2.1]hept-5-enes, the endo-trimethylsilyl-exo-S-oxide and their S,S-dioxide derivatives were protiodesilylated with fluoride ion. Stereoconvergent reactions were found, affording the endo-phenyl derivatives. These results can be rationalised with the hypothesis of a common carbanionic intermediate. In contrast, the desilylation of 3-endo-trimeth