A mild, practical, and environmentally friendly route to vinyl sulfones and sulfonamides has been developed based on the reaction of aliphaticamines with arenesulfonyl chlorides in the presence of eosin Y as a photocatalyst under visible light. The method permits the selective formation of vinyl sulfones or sulfonamides, depending on the oxidation environment and solvent. A wide range of products
Tosvinyl and Besvinyl as Protecting Groups of Imides, Azinones, Nucleosides, Sultams, and Lactams. Catalytic Conjugate Additions to Tosylacetylene
作者:Elena Petit、Lluís Bosch、Joan Font、Laura Mola、Anna M. Costa、Jaume Vilarrasa
DOI:10.1021/jo501647w
日期:2014.9.19
The use of the 2-(4-methylphenylsulfonyl)ethenyl (tosvinyl, Tsv) group for the protection of the NH group of a series of imides, azinones (including AZT), inosines, and cyclic sulfonamides has been examined. The Tsv-protected derivatives are obtained in excellent yields by conjugate addition to tosylacetylene (ethynyl p-tolyl sulfone). The stereochemistry of the double bond can be controlled at will:
Direct C(
<i>sp</i>
<sup>2</sup>
)‐H Arylsulfonylation of Enamides
<i>via</i>
Iridium(III)‐Catalyzed Insertion of Sulfur Dioxide with Aryldiazonium Tetrafluoroborates
An iridium(III)‐catalyzed three‐component reaction of enamides, aryldiazonium tetrafluoroborates, and 1,4‐diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO) for the direct C(sp2)−H arylsulfonylation of enamides is developed. This transformation provides a robust and straightforward approach for preparing a diverse array of β‐amidovinyl sulfones in moderate to excellent yields and high stereoselectivities