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
Intramolecular <i>ipso</i>-Halocyclization of 4-(<i>p</i>-Unsubstituted-aryl)-1-alkynes Leading to Spiro[4,5]trienones: Scope, Application, and Mechanistic Investigations
作者:Bo-Xiao Tang、Yue-Hua Zhang、Ren-Jie Song、Dong-Jun Tang、Guo-Bo Deng、Zhi-Qiang Wang、Ye-Xiang Xie、Yuan-Zhi Xia、Jin-Heng Li
DOI:10.1021/jo300037n
日期:2012.3.16
A new, general method for the synthesis of spiro[4,5]trienores is described by the intramolecular ipso-halocyclization of 4-(p-unsubstituted-aryl)-1-alkynes. In the presence of halide electrophiles, a variety of 4-(p-unsubstituted-aryl)-1-alkynes underwent the intramolecular ipso-halocyclization with water smoothly, affording the corresponding halo-substituted spiro[4,5]trienones in moderate to good yields. The obtained spiro[4,5]trienones can be applied in constructing the azaquaternary tricyclic skeleton via Pd-catalyzed Heck reaction. Notably, the prepared spiro[4,5]trienones and azaquaternary tricycles are of importance in the areas of pharmaceuticals and agrochemicals. The mechanism of the intramolecular ipso-halocyclization reaction is also discussed according to the O-18-labeling experiments and DFT calculations.