Transformations of<i>N</i>-Allyl-<i>N</i>-(phenylethynyl)arenesulfonamides into 2,2-Disubstituted 4-Pentenenitriles through Aza-Claisen Rearrangement that Follows Carbomagnesiation
作者:Hiroto Yasui、Hideki Yorimitsu、Koichiro Oshima
DOI:10.1246/cl.2007.32
日期:2007.1
Treatment of N-allyl-N-(phenylethynyl)arenesulfonamides with Grignard reagents under copper catalysis resulted in carbomagnesiation across the alkynyl parts. The carbomagnesiations yielded 2-magnesio-3-aza-1,5-hexadienes, which underwent the aza-Claisen rearrangement upon heating. The rearrangement followed by elimination of the arenesulfonyl groups provided 2,2-disubstituted 4-pentenenitriles.
Silylcupration and Copper-Catalyzed Carbomagnesiation of Ynamides: Application to Aza-Claisen Rearrangement
作者:Hiroto Yasui、Hideki Yorimitsu、Koichiro Oshima
DOI:10.1246/bcsj.81.373
日期:2008.3.15
Treatment of ynamides with silylcopper reagents resulted in silylcupration to afford (E)-β-silylenamides, after protonolysis, in good yields with high regio- and stereoselectivity. Reaction of ynamides having an allyl group on the nitrogen with Grignard reagents in the presence of a copper catalyst resulted in carbomagnesiation across the alkynyl unit and subsequent heating provided 4-pentenenitriles via aza-Claisen rearrangement.
Sulfilimines as Versatile Nitrene Transfer Reagents: Facile Access to Diverse Aza-Heterocycles
作者:Xianhai Tian、Lina Song、Matthias Rudolph、Frank Rominger、Thomas Oeser、A. Stephen K. Hashmi
DOI:10.1002/anie.201812002
日期:2019.3.11
We herein report the unprecedented synthesis of diverse biologically important aza‐heterocycles by employing sulfilimines as nitrenetransfer reagents. This class of sulfur‐based aza‐ylides had not been successfully used for gold nitrenetransfer before. This work contains an efficient generation of α‐imino gold carbenes by N−S cleavage of sulfilimines. These gold carbenes undergo C−H insertion, cyclopropanation
Keteniminium‐Driven Umpolung Difunctionalization of Ynamides
作者:Shubham Dutta、Shengwen Yang、Rajeshwer Vanjari、Rajendra K. Mallick、Vincent Gandon、Akhila K. Sahoo
DOI:10.1002/anie.201915522
日期:2020.6.26
synthesis of novel triaryl‐substituted enamides is described. This transformation represents the first example of an umpolung regioselective unsymmetrical syn ‐1,2‐diarylation/aryl‐olefination of ynamides. The aryl moieties of the diazonium salt (electrophile) and boronic acid (nucleophile) are explicitly incorporated in the electrophilic α‐ and nucleophilic β‐position, respectively, of the ynamide
Photoinduced oxidative cyclopropanation of ene-ynamides: synthesis of 3-aza[<i>n</i>.1.0]bicycles <i>via</i> vinyl radicals
作者:Yongming Deng、Jason Zhang、Bradley Bankhead、Jonathan P. Markham、Matthias Zeller
DOI:10.1039/d1cc02016a
日期:——
first photoinduced synthesis of polyfunctionalized 3-aza[n.1.0]bicycles from readily available ene-ynamides and 2,6-lutidine N-oxide using an organic acridinium photocatalyst is reported. Applying a photocatalytic strategy to the reactive distonic cation vinyl radical intermediate from ynamide, a series of bio-valuable 3-azabicycles, including diverse 3-azabicyclio[4.1.0]heptanes and 3-azabicyclo[5