Dual Photoredox/Nickel-Catalyzed 1,4-Sulfonylarylation of 1,3-Enynes with Sulfinate Salts and Aryl Halides: Entry into Tetrasubstituted Allenes
作者:Ting Xu、Shuang Wu、Quan-Na Zhang、You Wu、Ming Hu、Jin-Heng Li
DOI:10.1021/acs.orglett.1c03179
日期:2021.11.5
A radical-mediated three-component 1,4-sulfonylarylation of 1,3-enynes with aryl iodides and sulfinate salts using cooperativephotoredox/nickelcatalysis is described. This protocol enables the synthesis of tetrasubstituted sulfonyl-containing allenes under redox-neutral conditions and provides a versatile 1,3-enyne 1,4-difunctionalization platform for the synthesis of a diverse range of tetrasubstituted
A copper-catalyzed 1,4-addition reaction of sulfonyl iodides with 1,3-enynes affording various allenyl halides in high yields under mild conditions has been developed. Mechanistic studies showed that the reaction proceeds through a radical mechanism.
Synthesis of Polycyclic Compounds by a Cascade Cycloisomerisation/Diels-Alder Reaction
作者:José Barluenga、Jonás Calleja、Abraham Mendoza、Félix Rodríguez、Francisco J. Fañanás
DOI:10.1002/chem.201000515
日期:2010.6.25
Running rings around gold: A new cascade reactioncatalysed by AuCl3 that is based upon an initial cycloisomerisation reaction of enynol or enynamine derivatives, which form 1,3‐butadiene derivatives, followed by a Diels–Alder cycloaddition reaction to give fused or spirocyclic compounds is reported (see scheme).
Silver(I)-Catalyzed Cascade: Direct Access to Furans from Alkynyloxiranes
作者:Aurélien Blanc、Katharina Tenbrink、Jean-Marc Weibel、Patrick Pale
DOI:10.1021/jo900483m
日期:2009.6.5
Functionalized furans are conveniently formed by a new silver(I)-catalyzed reaction of alk-1-ynyl oxiranes in the presence of p-toluenesulfonic acid and methanol. Evidence supported a cascade mechanism.
Mechanistic Studies and Improvement of Coinage Metal-Catalyzed Transformation of Alkynyloxiranes to Furans: An Alcohol Addition−Cyclization−Elimination Cascade
作者:Aurélien Blanc、Katharina Tenbrink、Jean-Marc Weibel、Patrick Pale
DOI:10.1021/jo9008172
日期:2009.8.7
In the presence of alcohol Ag or Au salts or complexes catalyze the conversion of alkynyloxiranes to substituted furans. Both-catalysts are effective, and a large furan diversity can be obtained in high yield with one or the other catalyst. Mechanistic studies revealed that a cascade pathway and not the sometimes reported direct intra molecular nucleophilic addition of oxirane oxygen atom to intermediate acetylene-metal pi-complex occurs. Under the defined conditions, the intermediate formation of epoxide opening products has been identified. Depending on the catalyst, one or both of the latter cyclized to dihydrofurans, and further elimination of the alcohol led to the corresponding furans. These results highlight the duality between oxophilicity and alkynophilicity of Ag or Au salts.