An efficient and practical method for synthesis of C2‐phosphorylated indoles has been disclosed via a metal‐free 1,2‐phosphorylation of 3‐indolylmethanols with H‐phosphine oxides or H‐phosphonates. This alternative protocol features a broad substrate scope with respect to both 3‐indolylmethanols derived from isatins, acyclic α‐keto amide, α‐keto ester, 1,2‐diketone and simple ketones and H‐phosphine
3-Hydroxy-3-((3-methyl-4-nitroisoxazol-5-yl)methyl)indolin-2-one as a versatile intermediate for retro-Henry and Friedel–Crafts alkylation reactions in aqueous medium
retro-Henry type reaction is reported using 3-hydroxy-3-((3-methyl-4-nitroisoxazol-5-yl)methyl)indolin-2-ones which are prepared via catalyst-free Henry reaction of 3,5-dimethyl-4-nitroisoxazole and isatin. These compounds were used for the selective synthesis of 3-hydroxy-indolyl-2-oxindoles and bis-indolyl-2-oxindoles (symmetric/unsymmetric) via retro-Henry type reaction followed by Friedel–Crafts alkylation
Kaolin/KOH Is an Efficient Heterogeneous Catalyst for the Synthesis of 3-Hydroxy-3-indolyl Oxindoles
作者:G. Srihari、M. Marthanda Murthy
DOI:10.1080/00397911.2010.515342
日期:2011.9.15
3-Hydroxy-3-indolyl oxindoles were synthesized from isatins and indoles in good to excellent yields by using heterogeneous catalyst kaolin preloaded with KOH.