Aryldiazenyl Radicals from Arylazo Sulfones: Visible Light‐Driven Diazenylation of Enol Silyl Ethers
作者:Havall Othman Abdulla、Simone Scaringi、Ahmed A. Amin、Mariella Mella、Stefano Protti、Maurizio Fagnoni
DOI:10.1002/adsc.201901424
日期:2020.5.26
A versatile protocol for the diazenylation of enolsilylethers under visible light irradiation is presented herein. The reaction is based on the underused reaction of a nitrogen‐based radical (the diazenyl radical) with an enolsilylether. Arylazo sulfones were used as photoactivatable precursors of these diazenyl radicals. The resulting azaderivatives are potentially bioactive compounds as well
corresponding triflates, are subject to nucleophile-triggered fragmentation as part of a tandem process for generating functionalized alkynes. Advantages to the use of nonaflates in lieu of triflates include cost and stability. Computational analysis supports a postulated fragmentation mechanism involving a closed (cyclic) transition state with concerted extrusion of lithium sulfonate. Vinylogous acyl nonaflates
N‐Heterocyclic Carbene Catalyzed Synthesis of δ‐Sultones via α,β‐Unsaturated Sulfonyl Azolium Intermediates
作者:Andrei Ungureanu、Alison Levens、Lisa Candish、David W. Lupton
DOI:10.1002/anie.201504633
日期:2015.9.28
A limited array of reactive intermediates have enabled a wealth of discoveries in N‐heterocycliccarbene organocatalysis. In this study, the viability of α,β‐unsaturatedsulfonylazoliums as double electrophiles in new reactions is examined. Specifically, the (3+3) annulation of such species with the trimethylsilyl enol ethers of various 1,3‐dicarbonyl compounds has been developed. This reaction provides
The synthesis of angularly fused aromatic ring systems. The synthesis of 3-deoxyrabelomycin
作者:George A. Kraus、Yusheng Wu
DOI:10.1016/s0040-4039(00)79380-4
日期:1991.7
3-deoxyrabelomycin was synthesized from the electron-deficient naphthoquinone 21 in four steps in 17% overall yield. The angularly-fused ring system was made by the conjugate addition of 5-methylcyclohexane-1,3-dione to 21 followed by methylation and base-induced cyclization.