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
Palladium-Catalyzed Conjugate Addition to Electron-Deficient Alkynes with Benzenesulfinic Acid Derived from 1,2-Bis(phenylsulfonyl)ethane: Selective Synthesis of (<i>E</i>)-Vinyl Sulfones
作者:Ren-Jie Song、Yu Liu、Yan-Yun Liu、Jin-Heng Li
DOI:10.1021/jo102359n
日期:2011.2.4
A new, selective method for the synthesis of (E)-vinyl sulfones is presence by palladium-catalyzed C−S bond cleavage/conjugate addition. In the presence of Pd(OAc)2 and DMEDA (N1,N2-dimethylethane-1,2-diamine), 1,2-bis(phenylsulfonyl)ethane underwent the C−S bond cleavage, followed by conjugate addition to numerous electron-deficient alkynes afforded the corresponding (E)-vinyl sulfones in moderate
Electrophilic <i>ipso</i>-Halocyclization
of <i>N</i>-Arylpropynamides with Polyfluoroalkyl
Alcohols: Selective Synthesis of 8-(Polyfluoroalkoxy)azaspiro[4.5]trienes
作者:Zhi-Qiang Wang、Bo-Xiao Tang、Hong-Ping Zhang、Feng Wang、Jin-Heng Li
DOI:10.1055/s-0028-1087972
日期:——
polyfluoroalkyl alcohols. In the presence of N-halosuccinimides (NXS), a variety of N-arylpropynamides underwent an electrophilic ipso-halocyclization reaction with polyfluoroalkyl alcohols to afford the corresponding 8-(polyfluoroalkoxy)spiro[4.5]trienes in good yields. Note that molecular sieves can improve the yield of the reaction. electrophilic ipso-halocyclization - N-arylpropynamide - N-halosuccinimide