53512-44-0Relevant academic research and scientific papers
N-Chlorophthalimide as a mild and efficient chlorination reagent in the Gassman ortho alkylation of aromatic amines. Synthesis of 3-(methylthio)oxindoles
Cybulski, Marcin,Formela, Adam,Fokt, Izabela
, p. 5423 - 5425 (2014)
A practical modification of the Gassman 3-(methylthio)oxindole synthesis is reported. In our method, substituted anilines and 2-(methylthio)acetamide were reacted under mild reaction conditions, in the presence of N-chlorophthalimide as a chlorinating agent to give α-amidosulfides, which, in the next step of the process, were cyclized to give 3-(methylthio)oxindoles. The method was successfully applied for the synthesis of the key intermediate, 2-(2-amino-3-benzoylphenyl)-2-(methylthio)acetamide, in the process of the preparation of nepafenac, a commonly used ophthalmic drug.
Synthesis of oxindoles from anilines and β-thio carboxylic esters or amides
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, (2008/06/13)
Preparing oxindoles and intermediates therefor by reacting an N-haloaniline with β-thio esters or β-thio amides to form an azasulfonium halide, reacting the azasulfonium halide with a base to form an ortho-[thio-ether (hydrocarbonoxycarbonyl) alkyl]aniline, or a [thio-ether (aminocarbonyl) alkyl]aniline, reacting the orthosubstituted aniline with an acid to form a 3-thio-ether-2-oxindole, and then reducing the 3-thio-ether-2-oxindole with Raney Nickel to form the 2-oxindole.
