Transition-Metal-Free Synthesis of Oxindoles by Potassium tert-Butoxide-Promoted Intramolecular α-Arylation
摘要:
Potassium tert-butoxide-mediated intramolecular alpha-arylations of fluoro- and chloro-substituted anilides provide oxindoles in DMF at 80 degrees C. In this manner, diversely substituted products have been obtained in moderate to high yields.
Photoredox‐Catalyzed Tandem Demethylation of
<i>N</i>
,
<i>N</i>
‐Dimethyl Anilines Followed by Amidation with α‐Keto or Alkynyl Carboxylic Acids
作者:Pritha Das、Hasina Mamataj Begam、Samir Kumar Bhunia、Ranjan Jana
DOI:10.1002/adsc.201900525
日期:2019.9.3
for highly selective monodemethylation of N,N‐dimethyl anilines to generate secondary amines and subsequent coupling with α‐ketocarboxylic acids or alkynyl carboxylic acids to form α‐ketoamides or alkynamides respectively undervisiblelight photoredox catalyst in a single operation. From the deuterium‐labeling experiment, it was probed that demethylation is the slowest step in this tandem process
Multiple Aryne Insertions into Oxindoles: Synthesis of Bioactive 3,3-Diarylated Oxindoles and Dibenzo[<i>b</i>,<i>e</i>]azepin-6-ones
作者:Ramesh Samineni、Chandramohan Reddy C. Bandi、Pabbaraja Srihari、Goverdhan Mehta
DOI:10.1021/acs.orglett.6b03224
日期:2016.12.2
bioactive di- and triarylated oxindoles in good yields under mild conditions. A temperature controlled “reaction switch” enables ready access to dibenzo[b,e]azepin-6-one derivatives employing the same reaction regime. This tactic has been extended to a short synthesis of potent antiulcer agent darenzepine.
Transition metal and base-free synthesis of 3,3-diaryl-2-oxindoles from 2,2,N-triarylacetamides
作者:Jin Woo Lim、Ko Hoon Kim、Hye Ran Moon、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2016.01.024
日期:2016.2
A transitionmetal and base-free synthesis of 3,3-diaryl-2-oxindoles has been developed from 2,2,N-triarylacetamides in the presence of montmorillonite K-10 in 1,2-dichlorobenzene under O2 balloon atmosphere.
Oxindole synthesis <i>via</i> polar–radical crossover of ketene-derived amide enolates in a formal [3 + 2] cycloaddition
作者:Niklas Radhoff、Armido Studer
DOI:10.1039/d1sc07134c
日期:——
and transition-metal free method for the preparation of valuable and sterically hindered 3,3-disubstituted oxindoles via polar–radical crossover of ketene derived amide enolates. Various easily accessible N-alkyl and N-arylanilines are added to disubstituted ketenes and the resulting amide enolates undergo upon single electron transfer oxidation a homolytic aromatic substitution (HAS) to provide 3,3-disubstituted
in the aromaticringvia metal-free catalysis is very important. In this regard, we have developed a facile metal-free, extremely selective, user-friendly, environmentally benign and cost-effective Friedel-Crafts (FC) alkylation protocol for 2-oxindoles and anilines with donor-acceptor cyclopropanes. Real-time NMR studies reveal that the transformation is governed by the cooperative catalysis of Brønsted