Ruthenium-catalyzed intramolecular cyclization of diazo-β-ketoanilides for the synthesis of 3-alkylideneoxindoles
作者:Wai-Wing Chan、Tsz-Lung Kwong、Wing-Yiu Yu
DOI:10.1039/c2ob06985g
日期:——
With [Ru(p-cymene)Cl2]2 as catalyst, diazo-β-ketoanilides would undergo intramolecular carbenoid arene CâH bond functionalization to afford 3-alkylideneoxindoles in up to 92% yields. The reaction occurs under mild conditions and exhibits excellent chemoselectivity. The lack of primary KIE (kH/kD â¼ 1) suggests that the reaction should not proceed by rate-limiting CâH bond cleavage; a mechanism involving cyclopropanation of the arene is proposed.
Silver catalyzed intramolecular cyclization for synthesis of 3-alkylideneoxindoles via C–H functionalization
作者:Hong-Li Wang、Zhe Li、Gang-Wei Wang、Shang-Dong Yang
DOI:10.1039/c1cc14394h
日期:——
A novel protocol for the preparation of various 3-alkylideneoxindoles via a silver-catalyzed aromatic CâH functionalization has been developed. The process is simple, environmentally conscious, and avoids the use of abundant bases, oxidants, or other additives.
Aqueous Copper Nitrate Catalyzed Synthesis of 3-Alkylideneoxindoles from α-Diazo-β-ketoanilides
作者:Shanyan Mo、Zhanhui Yang、Jiaxi Xu
DOI:10.1002/ejoc.201402206
日期:2014.6
An economical, practical, and green protocol with which to synthesize 3-alkylideneoxindolesfromα-diazo-β-ketoanilides has been developed. The approach employs inexpensive Cu(NO3)2·3H2O as catalyst and environmentally friendly water as solvent, and achieves moderate to excellent yields. The method has good tolerance to a range of N-alkyl and N-aryl groups, including electron-withdrawing and electron-donating