remote cross Rauhut−Currier reaction utilizing vinyl ketones and para‐quinone methides derived from isatins was realized, which was successfully catalyzed using bifunctional phosphines, furnishing chiral 3,3‐disubstituted oxindoles in excellent enantioselectivities and high yields. The mechanistic studies demonstrated the key role of the alkyl hydrogen of the vinyl ketones, which conceivably interacted
Enantioselective Copper-Catalyzed [3 + 3] Cycloaddition of Tertiary Propargylic Esters with 1<i>H</i>-Pyrazol-5(4<i>H</i>)-ones toward Optically Active Spirooxindoles
作者:You-Wei Xu、Ling Li、Xiang-Ping Hu
DOI:10.1021/acs.orglett.0c03587
日期:2020.12.18
A copper-catalyzed enantioselective [3 + 3] cycloaddition of 3-ethynyl-2-oxoindolin-3-yl acetates with 1H-pyrazol-5(4H)-ones for the construction of optically active spirooxindoles bearing a spiro all-carbon quaternarystereocenter has been realized. With a combination of Cu(OTf)2 and chiral tridentate ketimine P,N,N-ligand as the catalyst, the reaction displayed broad substrate scopes, good yields
Syntheses of Spirocyclic Oxindole-Butenolides by Using Three-Component Cycloadditions of Isocyanides, Allenoates, and Isatins
作者:Jian Li、Yuejin Liu、Chunju Li、Xueshun Jia
DOI:10.1002/chem.201100977
日期:2011.6.27
Spiro workflow! Efficient syntheses of spirocyclic oxindole‐butenolides from readily available isocyanides, allenoates, and isatins are disclosed (see scheme; R1=alkyl, aryl; R2=halide, nitro, methoxy; PG=protecting group). This protocol also allows the insertion of carbon monoxide into organic molecules without the aid of a transition‐metal catalyst after the hydrolysis process.
Spiro工作流程!公开了由容易获得的异氰化物,烯醇酸酯和异族素有效合成螺环氧基吲哚-丁烯内酯的方法(参见方案; R 1 =烷基,芳基; R 2 =卤化物,硝基,甲氧基; PG =保护基)。该方案还允许在水解过程后无需过渡金属催化剂的帮助下将一氧化碳插入有机分子。
Asymmetric Synthesis of Spiro-epoxyoxindoles by the Catalytic Darzens Reaction of Isatins with Phenacyl Bromides
The asymmetricDarzensreaction between phenacyl bromides and N-protected isatins was developed to synthesize potentially bioactive spiro-epoxyoxindoles. The optically active products were obtained in moderate to good yields and enantioselectivities catalyzed by chiral N,N′-dioxide-Co(acac)2 complexes. A retro-aldol process accompanying the ring-closure step was observed in the process. A chiral control
Dialkyl Phosphite-Initiated Cyclopropanation of α,β-Unsaturated Ketones Using α-Ketoesters or Isatin Derivatives
作者:Deng Yin、Hui Liu、Chong-Dao Lu、Yan-Jun Xu
DOI:10.1021/acs.joc.6b03009
日期:2017.3.17
cyclopropanation of α,β-unsaturatedketones using α-ketoesters or isatin derivatives is reported. The cyclopropanation reaction occurs via a cascade transformation that starts with addition of deprotonated dialkyl phosphite to the keto groups of α-ketoesters or isatin derivatives, followed by [1,2]-phosphonate/phosphate rearrangement to generate α-phosphonyloxyenolate intermediates, which are trapped by α,β-unsaturated