The first facile one‐pot synthesis of sulfone‐containing oxindoles with easily accessible disulfides as the sulfonylating precursors is described. This reaction occurs smoothly under transition metal‐free conditions and shows excellent functional group tolerance, allowing the facile and efficient green synthesis of various sulfone‐containing oxindoles in aqueous solution. Preliminary mechanistic studies
描述了第一个简便的单锅合成含砜的吲哚类化合物,其中二硫醚作为磺酰化的前体很容易获得。该反应在不含过渡金属的条件下可平稳进行,并具有出色的官能团耐受性,可在水溶液中轻松高效地绿色合成各种含砜的羟吲哚。初步的机理研究表明,水(H 2 O)和过硫酸钾(K 2 S 2 O 8)均可以是产物中砜基的氧源。
Catalyst-free direct arylsulfonylation of N-arylacrylamides with sulfinic acids: a convenient and efficient route to sulfonated oxindoles
作者:Wei Wei、Jiangwei Wen、Daoshan Yang、Juan Du、Jinmao You、Hua Wang
DOI:10.1039/c4gc00231h
日期:——
A catalyst-free procedure has been developed for the construction of sulfonated oxindoles via direct arylsulfonylation of activated alkenes with sulfinic acids.
visible-light-driven cascade cyclization reaction to synthesize 3-methyl-3-acetophenone-2-oxindoles and 3-methyl-3-(methylsulfonyl)benzene-2-oxindoles in yields up to 96% and 99%, via benzoyl and phenylsulfinyl radicals with acrylamide derivatives is reported, respectively. Extensive studies, including gram-scale, radical capture and isotope experiments, were performed to indicate that the reaction may involve a radical
Transition-Metal-Free TBAI-Facilitated Addition–Cyclization of<i>N</i>-Methyl-<i>N</i>-arylacrylamides with Arylaldehydes or Benzenesulfonohydrazides: Access to Carbonyl- and Sulfone-Containing<i>N</i>-Methyloxindoles
A highly efficient addition cyclization of Nmethyl-N-arylacrylamides with arylaldehydes or benzene-sulfonohydrazides was developed using a catalytic amount of the quaternary ammonium salt (TBAI) under metal-free conditions, leading to the carbonyl- and sulfone-containing oxindoles. Compared to previous Methods, which require excessive amounts of explosive organic peroxides and precious or toxic metal reagents, the present protocol, which gave access to 3,3-disubstituted oxindoles, is,a safe and green approach, resulting in the formation of various useful carbonyl- and sulfone-containing oxindoles in yields of 40-94%.