An efficient nickel/copper‐catalyzed decarbonylative silylation reaction of carboxylic acid esters with silylboranes is described. This reaction provides access to structurally diverse silanes with ...high efficiency and excellent functional‐group tolerance starting from readily available esters.
Copper and nickel: An efficient nickel/copper‐catalyzed decarbonylative silylation reaction of carboxylic acid esters with silylboranes is described. This process provides access to structurally diverse aryl‐ and heteroarylsilanes directly from the corresponding esters and benefits from superior functional‐group tolerance.
A ligand-controlled and site-selective nickel catalyzed Suzuki–Miyaura cross-coupling reaction with aromatic esters and alkyl organoboron reagents as coupling partners was developed. This methodology ...provides a facile route for C(sp2)–C(sp3) bond formation in a straightforward fashion by successful suppression of the undesired β-hydride elimination process. By simply switching the phosphorus ligand, the ester substrates are converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of key intermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas nickel complexes with bidentate ligands favor the C(aryl)–C bond cleavage in the oxidative addition step leading to the alkylated product via a decarbonylative process, nickel complexes with monodentate phosphorus ligands favor activation of the C(acyl)–O bond, which later generates the ketone product.
A nickel-catalyzed deamidative cross-coupling reaction of amides with terminal alkynes as coupling partners was disclosed. This newly developed methodology allows the direct interconversion of amides ...to alkynes and enables a facile route for C(sp2)–C(sp) bond formation in a straightforward and mild fashion.
An efficient nickel-catalyzed decarbonylative cyanation reaction which allows the direct functional-group interconversion of readily available esters into the corresponding nitriles was developed. ...This reaction successfully offers access to structurally diverse nitriles with high efficiency and excellent functional-group tolerance and provides a good alternative to classical synthetic pathways from diazonium salts or organic halide compounds.
Aza‐ortho‐quinone methides allow the straightforward asymmetric synthesis of natural‐product‐inspired indole scaffolds possessing a quaternary stereocenter. Our approach provides access to diverse ...communesin and spiroindoline derivatives with high enantioselectivity under mild reaction conditions. Predictable substitution patterns are found to be the key to our regiodivergent protocols.
Two protocols have been developed for the regiodivergent, asymmetric Brønsted acid catalyzed addition of indoles to in situ generated aza‐ortho‐quinone methides. Furthermore, a new addition spirocyclization sequence leads, depending on the indole derivative, to communesin and spiroindoline cores with quaternary stereocenters.
A simple and efficient catalytic system for a chemo- and regioselective ortho-alkenylation of anilines is presented. The new magnesium-catalyzed reaction allows the use of a wide range of alkynes and ...anilines with different electronic and steric properties and provides free as well as protected anilines with excellent yields.
An efficient nickel/copper‐catalyzed decarbonylative silylation reaction of carboxylic acid esters with silylboranes is described. This reaction provides access to structurally diverse silanes with ...high efficiency and excellent functional‐group tolerance starting from readily available esters.
Kupfer und Nickel: Eine effiziente Nickel/Kupfer‐katalysierte decarbonylierende Silylierung von Carbonsäureestern mit Silylboranen wird beschrieben. Diese Umsetzung bietet Zugang zu strukturell vielfältigen Aryl‐ und Heteroarylsilanen direkt aus den entsprechenden Estern und toleriert eine Vielzahl funktioneller Gruppen.
A nickel catalyzed cross‐coupling protocol for the straightforward C−S bond formation has been developed. Various mercaptans and a wide range of ester and amide substrates bearing various ...substituents were tolerated in this process which afforded products in good to excellent yields. Furthermore, an intramolecular protocol for the synthesis of thioethers starting from thioesters has been developed. The utility of this protocol has been demonstrated in a new synthetic protocol of benzothiophene.
A nickel catalyzed cross‐coupling protocol for facile C−S bond formation was developed. Various thiols and a wide range of ester and amide substrates bearing various substituents were tolerated in this process which afforded products in good to excellent yields. An intramolecular protocol for the synthesis of thioethers starting from thioesters was also developed and its utility was demonstrated in the synthesis of benzothiophene on the bench top.
An enantioselective addition of thiols and alcohols to aza‐ortho‐quinone methides, starting from diaryl methanols, was developed. The asymmetric additions occur under mild reaction conditions in the ...presence of chiral phosphoric acids and furnish the corresponding adducts with excellent yields and enantioselectivities.
Take two: An enantioselective addition of thiols and alcohols to aza‐ortho‐quinone methides, starting from diaryl methanols, has been developed. The asymmetric oxa‐ and sulfa‐Michael additions proceed under mild reaction conditions in the presence of chiral phosphoric acids to furnish the corresponding adducts with excellent yields and enantioselectivities.
PhSCF2TMS was utilized as a useful gem‐difluoromethylene building block for the synthesis of gem‐difluoromethylenated spiro‐γ‐butyrolactones. The radical cyclization of ...γ‐alkenyl‐γ‐gem‐difluoro(phenylsulfanyl)methyl‐γ‐butyrolactones provided gem‐difluoromethylenated spiro‐γ‐butyrolactones.
PhSCF2TMS (TMS = trimethylsilyl) is utilized as a gem‐difluoromethylenating agent for the synthesis of gem‐difluoromethylenated spiro‐γ‐butyrolactones.
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