695-34-1Relevant articles and documents
Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 1618 - 1629 (2021/01/25)
Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
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.
Syntheses, spectroscopy, electrochemistry, EPR, PXRD-structure and DFT/TD-DFT of bis[2-oxo-1-naphthaldehydato-κO,O’]copper(II)
Enamullah, Mohammed,Joy, Baitul Alif,Islam, Mohammad Khairul
, p. 56 - 64 (2018/09/18)
Reaction of N-2-(R-pyridyl)-2-hydroxy-1-naphthaldimine {R = H (HL1), 4-CH3 (HL2) and 6-CH3 (HL3)} with copper(II) nitrate provides the new complex of bis[2-oxo-1-naphthaldehydato-κO,O’]copper(II) (1) via in-situ hydrolysis of the Schiff base back to 2-hydroxy-1-naphthaldehyde (HL′). Elemental analyses reveal that there are no nitrogen atoms in the complex. X-ray diffraction (PXRD) data indicate that the complex is monoclinic with space group P21/a and Z = 2 and that the ligand acts as bidentate through O?O-chelate system forming a bis-complex with O2O2-coordination sphere around the copper(II) ion. Electrochemical results show two quasi-reversible one electron charge transfer processes attributed to [Cu(L′)2]2?/[Cu(L′)2]? and [Cu(L′)2]?/[Cu(L′)2] (L’ = deprotonated aldehyde) couples in acetonitrile. The magnetic data confirm the paramagnetic property of the complex with one unpaired electron in the metallic centre. The results suggest that the complex assumes a geometry between tetrahedral and square-planar supported by DFT calculations. Thermal analysis shows an irreversible phase transformation from solid to isotropic liquid phase. EPR spectrum in chloroform exhibits an isotropic pattern with four lines due to nuclear hyperfine splitting from the copper(II) ion with spin 3/2. The structural analyses, electrochemical and paramagnetic properties of these complexes explore greater interests for their use in the supramolecular chemistry.