6533b860fe1ef96bd12c3209
RESEARCH PRODUCT
From Benzofurans to Indoles: Palladium-Catalyzed Reductive Ring-Opening and Closure via β-Phenoxide Elimination
Raymond GrüberRaymond GrüberLuca Alessandro PeregoLuca Alessandro PeregoLaurent El KaimSimon WagschalSimon WagschalPaul Fleurat-lessardPaul Fleurat-lessardLaurence Grimaudsubject
Indole test010405 organic chemistryChemistry[CHIM.ORGA]Chemical Sciences/Organic chemistryClosure (topology)chemistry.chemical_elementbenzofuranGeneral Chemistry[CHIM.CATA]Chemical Sciences/Catalysis010402 general chemistryRing (chemistry)palladium01 natural sciencesMedicinal chemistry0104 chemical sciencesCatalysischemistry.chemical_compoundHeck reactionindoleHeck reaction[CHIM]Chemical SciencesBenzofuranring openingComputingMilieux_MISCELLANEOUSPalladiumdescription
International audience; Benzofurans can undergo ring-opening by a palladium-catalyzed process resulting in C−O bond breaking. Benzofuran-tethered 2-iodoanilines give synthetically interesting 2-(3-indolylmethyl)phenols in an overall reductive process. Mechanistic studies suggest that this unusual reaction proceeds by carbopalladation of benzofuran giving a 3-palladated 2,3-dihydrobenzofuran intermediate, which then fragments by an uncommon trans-elimination of the phenoxide group β to the metal. In this transformation, N,N-diisopropylethylamine (DIPEA) acts as a base and as a reducing agent: it regenerates palladium(0) from palladium(II), thus allowing catalytic turnover.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2018-01-01 |