Electrophilic ipso-Iodocyclization of N-(4-Methylphenyl)propiolamides: Selective Synthesis of 8-Methyleneazaspiro[4,5]trienes
摘要:
[GRAPHICS]A novel and selective method for the synthesis of 8-methylenespiro[4,5]trienes via intramolecular electrophilic ipsoiodocyclization of N-(4-methylphenyl)propiolamides has been developed. In the presence of ICI or I-2, 8-methylene-1-azaspiro[4,5]trienes were selectively prepared from the electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides in moderate to good yields.
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