We report the first organocatalytic asymmetric synthesis of 3,3-disubstituted oxindoles featuring two heteroatoms at the C3 position. Importantly, 3-thiooxindoles and 3-alkoxyoxindoles are demonstrated to be reactive nucleophiles for the development of catalytic asymmetric reactions for the first time.
Alkoxylation Followed by Iodination of Oxindole with Alcohols Mediated by Hypervalent Iodine Reagent in the Presence of Iodine
作者:Rajendraprasad Kotagiri、Ramesh Adepu
DOI:10.1002/ejoc.201800723
日期:2018.9.9
Iodoalkoxylation of oxindole with alcohols was achieved by using a hypervalentiodine species in combination with iodine under metal‐free conditions. This method is useful for the synthesis of 3‐alkoxy oxindole, 5‐iodo‐3‐alkoxy oxindole and 5‐iodo‐3,3‐dialkoxy oxindole by sequentially in moderate to good yields.
Synergistic-Catalysis-Enabled Reaction of 2-Indolymethanols with Oxonium Ylides for the Construction of 3-Indolyl-3-Alkoxy Oxindole Frameworks
作者:Chun Ma、Jia-Yu Zhou、Yi-Zhu Zhang、Yinchun Jiao、Guang-Jian Mei、Feng Shi
DOI:10.1002/asia.201800620
日期:2018.9.4
synergistic‐catalysis‐enabled reaction of 2‐indolymethanols with oxoniumylides has been established that makes use of a three‐component reaction between 3‐diazooxindoles, alcohols, and 2‐indolymethanols under the cooperative catalysis of a metal complex and a Brønsted acid. This reaction has not only provided a new approach for the construction of 3‐indolyl‐3‐alkoxy oxindole scaffolds by utilizing the
Herein, we present a general electrochemical method to access unsymmetrical 3,3-disubstituted oxindoles by direct C–H functionalization where the oxindole fragment behaves as an electrophile. This Umpolung approach does not rely on stoichiometric oxidants and proceeds under mild, environmentally benign conditions. Importantly, it enables the functionalization of these scaffolds through C–O, and by
Selective Insertion of Alkynes into C–C σ Bonds of Indolin-2-ones: Transition-Metal-Free Ring Expansion Reactions to Seven-Membered-Ring Benzolactams or Chromone Derivatives
作者:Mengdan Wang、Yajie Yang、Bo Song、Liqiang Yin、Shuhui Yan、Yanzhong Li
DOI:10.1021/acs.orglett.9b04081
日期:2020.1.3
An unprecedented ring expansion reaction of indolin-2-ones with alkynyl ketones under transition-metal-free conditions has been developed. Base-promoted selective cleavage of a C-Cσbond of the amide is the key in this process, which provides a straightforward and efficient way to synthesize seven-membered-ring benzolactams or chromone derivatives. The significant advantages of this method include