4058-18-8Relevant articles and documents
Reductive C?N Coupling of Nitroarenes: Heterogenization of MoO3 Catalyst by Confinement in Silica
Yang, Fu,Dong, Xuexue,Shen, Yang,Liu, Mengting,Zhou, Hu,Wang, Xuyu,Li, Lulu,Yuan, Aihua,Song, Heng
, p. 3413 - 3421 (2021/07/31)
The construction of C?N bonds with nitroaromatics and boronic acids using highly efficient and recyclable catalysts remains a challenge. In this study, nanoporous MoO3 confined in silica serves as an efficient heterogeneous catalyst for C?N cross-coupling of nitroaromatics with aryl or alkyl boronic acids to deliver N-arylamines and with desirable multiple reusability. Experimental results suggest that silica not only heterogenizes the Mo species in the confined mesoporous microenvironment but also significantly reduces the reaction induction period and regulates the chemical efficiency of the targeted product. The well-shaped MoO3@m?SiO2 catalyst exhibits improved catalytic performance both in yield and turnover number, in contrast with homogeneous Mo catalysts, commercial Pd/C, or MoO3 nanoparticles. This approach offers a new avenue for the heterogeneous catalytic synthesis of valuable bioactive molecules.
Design, preparation and characterization of aerogel NiO-CuO-CoO/SiO2 nanocomposite as a reusable catalyst for C-N cross-coupling reaction
Ghasemi, Amir Hossein,Naeimi, Hossein
supporting information, p. 5056 - 5063 (2020/04/09)
Aerogels are porous, non-crystalline solid materials with high specific surface space, plentiful three-dimensional (3D) porous construction, ultra-low density and significant porosity. The aerogel nanocomposite is produced using sol-gel and supercritical drying processes. CO2 supercritical drying (SCD) is the most powerful process, ensuring optimal product properties such as high porosity, low density, and high thermal conductivity. On this account, we used the CO2 supercritical drying method to produce NiO-CuO-CoO/SiO2 nanocomposite aerogels and applied it as a reusable catalyst for the C-N cross-coupling reaction (Buchwald-Hartwig amination). Powerful catalytic activity for the C-N cross-coupling reaction was obtained for the new nanocomposite aerogel, that is, NiO-CuO-CoO/SiO2. The catalyst was characterized by X-ray Powder Diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), elemental mapping and Brunauer-Emmett-Teller (BET). Also, organic compounds were identified by melting point, Fourier-transform infrared spectroscopy (FT-IR) and hydrogen-1 nuclear magnetic resonance (1H NMR) analyses.
Reductive Molybdenum-Catalyzed Direct Amination of Boronic Acids with Nitro Compounds
Suárez-Pantiga, Samuel,Hernández-Ruiz, Raquel,Virumbrales, Cintia,Pedrosa, María R.,Sanz, Roberto
supporting information, p. 2129 - 2133 (2019/01/25)
The synthesis of aromatic amines is of utmost importance in a wide range of chemical contexts. We report a direct amination of boronic acids with nitro compounds to yield (hetero)aryl amines. The novel combination of a dioxomolybdenum(VI) catalyst and triphenylphosphine as inexpensive reductant has revealed to be decisive to achieve this new C?N coupling. Our methodology has proven to be scalable, air and moisture tolerant, highly chemoselective and engages both aliphatic and aromatic nitro compounds. Moreover, this general and step-economical synthesis of aromatic secondary amines showcases orthogonality to other aromatic amine syntheses as it tolerates aryl halides and carbonyl compounds.
