328-74-5Relevant articles and documents
Stereoselective Synthesis of Pyrroloquinolines by a Br?nsted Acid Catalyzed [4+2]-Heterocyclization of Indole-7-Carbaldehydes, Anilines and Electron-Rich Alkenes
Galván, Alicia,Fontaneda, Raquel,Fa?anás, Francisco J.,Rodríguez, Félix
, p. 1741 - 1745 (2016)
The pyrrolo[3,2,1-ij]quinoline heterocyclic core is found in the structure of a variety of compounds with interesting applications and then, new efficient and flexible strategies to construct this skeleton are required. Here, a new diastereoselective tetrafluoroboric acid (HBF4)-catalyzed three-component coupling reaction of 1H-indole-7-carbaldehyde derivatives, anilines and electron-rich alkenes to give pyrrolo[3,2,1-ij]quinolines is described. The reaction involves an unusual [4+2]-heterocyclization between an in situ formed imine and an alkene. The new catalytic method, where water is the only by-product, is efficient, robust and flexible, and allows for multigram-scale synthesis.
Electronic Structures and Reactivity Profiles of Aryl Nitrenoid-Bridged Dicopper Complexes
Carsch, Kurtis M.,Lukens, James T.,Dimucci, Ida M.,Iovan, Diana A.,Zheng, Shao-Liang,Lancaster, Kyle M.,Betley, Theodore A.
supporting information, p. 2264 - 2276 (2020/02/18)
Dicopper complexes templated by dinucleating, pacman dipyrrin ligand scaffolds (Mesdmx, tBudmx: Dimethylxanthine-bridged, cofacial bis-dipyrrin) were synthesized by deprotonation/metalation with mesitylcopper (CuMes; Mes: Mesityl) or by transmetalation with cuprous precursors from the corresponding deprotonated ligand. Neutral imide complexes (Rdmx)Cu2(μ2-NAr) (R: Mes, tBu; Ar: 4-MeOC6H4, 3,5-(F3C)2C6H3) were synthesized by treatment of the corresponding dicuprous complexes with aryl azides. While one-electron reduction of (Mesdmx)Cu2(μ2-N(C6H4OMe)) with potassium graphite initiates an intramolecular, benzylic C-H amination at room temperature, chemical reduction of (tBudmx)Cu2(μ2-NAr) leads to isolable [(tBudmx)Cu2(μ2-NAr)]-product salts. The electronic structures of the thermally robust [(tBudmx)Cu2(μ2-NAr)]0/-complexes were assessed by variable-temperature electron paramagnetic resonance spectroscopy, X-ray absorption spectroscopy (Cu L2,3/K-edge, N K-edge), optical spectroscopy, and DFT/CASSCF calculations. These data indicate that the formally Class IIIA mixed valence complexes of the type [(Rdmx)Cu2(μ2-NAr)]-feature significant NAr-localized spin following reduction from electronic population of the [Cu2(μ2-NAr)] ? manifold, contrasting previous methods for engendering iminyl character through chemical oxidation. The reactivity of the isolable imido and iminyl complexes are examined for prototypical radical-promoted reactivity (e.g., nitrene transfer and H-atom abstraction), where the divergent reactivity is rationalized by the relative degree of N-radical character afforded from different aryl substituents.
Copper(ii)-catalyzed c-n coupling of aryl halides and n-nucleophiles promoted by quebrachitol or diethylene glycol
Chen, Guoliang,Chen, Yuanguang,Du, Fangyu,Fu, Yang,Wu, Ying,Zhou, Qifan
supporting information, p. 2161 - 2168 (2019/11/25)
Herein, we report the natural ligand quebrachitol (QCT) as a promoter for a Cu(II) catalyst, which is highly effective for N-Arylation of various amines and related aryl halides. A series of diarylamine derivatives were obtained in high yields by using diethylene glycol (DEG) as both ligand and solvent. The C-N coupling reactions proceed under mild conditions and exhibit good functional group tolerance.
