40800-77-9Relevant articles and documents
Asymmetric synthesis of pyrrolidinoindolines. Application for the practical total synthesis of (-)-phenserine
Huang, Audris,Kodanko, Jeremy J.,Overman, Larry E.
, p. 14043 - 14053 (2007/10/03)
A versatile route to enantiopure 3,3-disubstituted oxindoles and 3a-substituted pyrrolidinoindolines is described in which diastereoselective dialkylation of enantiopure ditriflate 10 with oxindole enolates is the central step. These reactions are rare examples of alkylations of prostereogenic enolates with chiral sp3 electrophiles that proceed with high facial selectivity (10-20:1). The scope of this method is explored, and a model to rationalize the sense of stereoselection is advanced. This dialkylation chemistry was used to synthesize (-)-phenserine on a multigram scale in six steps and 43% overall yield from 5-methoxy-1,3-dimethyloxindole (27) and to complete a short formal total synthesis of (-)-physostigmine (2).
A VERSATILE AND EFFICIENT PROCESS TO 3-SUBSTITUTED INDOLES FROM ANILINES
Wierenga, Wendell,Griffin, John,Warpehoski, Martha A.
, p. 2437 - 2440 (2007/10/02)
Borane-mediated reductive elimination of α-thiomethyl-, α-hydroxy-, or α-alkoxy-, α'-substituted oxindoles affords 3-substituted indoles in high yield.Isatins, available via several routes from oxindoles, also afford indoles.
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.