Abstract A new method for the synthesis of 3-thioazaspiro[4,5]trienones was developed using Pd nanoparticle catalysts, which are highly efficient, environmentally friendly and recyclable. Alkynes and thiophene phenols are effectively cyclized by Pd/ZrO2 catalyst under visible light irradiation. The present protocol simply utilizes visible light as the safe and ecofriendly energy source, and the Pd/ZrO2
Copper-Catalyzed Difunctionalization of Activated Alkynes by Radical Oxidation-Tandem Cyclization/Dearomatization to Synthesize 3-Trifluoromethyl Spiro[4.5]trienones
A copper‐catalyzed difunctionalizing trifluoromethylation of activated alkynes with the cheap reagent sodium trifluoromethanesulfinate (NaSO2CF3 or Langlois’ reagent) has been developed incorporating a tandem cyclization/dearomatization process. This strategy affords a straightforward route to synthesis of 3‐(trifluoromethyl)‐spiro[4.5]trienones, and presents an example of difunctionalization of alkynes
Transformations of N-arylpropiolamides to indoline-2,3-diones and acids via C≡C triple bond oxidative cleavage and C(sp2)–H functionalization
作者:Ming-Bo Zhou、Yang Li、Xuan-Hui Ouyang、Jin-Heng Li
DOI:10.1007/s11426-019-9633-x
日期:2020.2
A new palladium-catalyzed oxidative conversion of N-arylpropiolamides and H2O to various indoline-2,3-diones and acids through the C≡C triple bond cleavage and C(sp2)–H functionalization is described, which is promoted by a cooperative action of catalytic CuBr2, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and O2. The method provides a practical tool for transformations of alkynes by means of a C–H
Silver-catalyzed direct spirocyclization of alkynes with thiophenols: a simple and facile approach to 3-thioazaspiro[4,5]trienones
作者:Huanhuan Cui、Wei Wei、Daoshan Yang、Jimei Zhang、Zhihong Xu、Jiangwei Wen、Hua Wang
DOI:10.1039/c5ra16548b
日期:——
A new and convenient silver-catalyzed direct oxidative spirocyclization of alkynes with thiophenols is described. This methodology provides a simple and practical approach to various 3-thioazaspiro[4,5]trienones in moderate to good yields with high atom efficiency and excellent functional group tolerance.