405-67-4Relevant articles and documents
A highly efficient Co-based catalyst fabricated by coordination-assisted impregnation strategy towards tandem catalytic functionalization of nitroarenes with various alcohols
Li, Guangming,Li, Jingfang,Li, Weizuo,Li, Xuewei,Li, Zhibin,Mao, Guijie,She, Wei,Wang, Jing
, p. 462 - 474 (2021/11/11)
A well-defined hexamethylenetetramine (abbreviated as HMTA) based two-dimensional (2D) MOFs metalloligand (termed Zn-HMTA), with free uncoordinated tertiary amine groups, has been synthesized via solution diffusion method for the first time. The crystal structure of 2D Zn-HMTA metalloligand was determined by the single crystal X-ray diffraction (SCXRD). The SCXRD and X-ray photoelectron spectroscopy (XPS) analyses have revealed that the 2D Zn-HMTA metalloligand is rich in- free tertiary amine groups, which are of strong coordination ability to transition metal ions (e.g. Ni2+, Co2+, Zn2+, Cu2+). As a result, a 2D bimetallic Co@Zn-HMTA MOFs was synthesized via coordination-assisted impregnation (CAI) strategy attributed to the unique feature of strong coordinated ability of free tertiary amine groups. Furthermore, a series of self-supported Co-ZnO-CN nanocatalysts were afforded upon the as-synthesized Co@Zn-HMTA MOFs served as a self-sacrificial template for pyrolysis at different temperatures. The optimized catalyst (termed as Co-ZnO@CN-CAI) demonstrated the excellent catalytic performance for hydrogenation-alkylation tandem reaction in comparison with the classic ZnO@CN composite (derived from Zn-HMTA MOFs) supported metallic Co catalyst (Co-ZnO@CN-IWI) prepared by incipient wetness impregnation method. Moreover, the kinetic study was also performed to confirm that the alkylation is the rate-determining step in the hydrogenation-alkylation tandem reaction. The origin of enhanced catalytic performance of Co-ZnO@CN-CAI and the role of Co@Zn-HMTA MOFs precursor have been explored by way of various characterizations, e.g. HADDF-STEM-EDS, SEM-EDS, 13C MAS NMR, XRD, Raman and XPS, etc. It is anticipated that the prepared low-cost and easily prepared 2D Zn-HMTA metalloligand will become a general template for synthesis of highly self-supported catalysts with coordination-assisted impregnation strategy (CAI) for various catalytic reactions.
Homogeneous cobalt-catalyzed deoxygenative hydrogenation of amides to amines
Papa, Veronica,Cabrero-Antonino, Jose R.,Spannenberg, Anke,Junge, Kathrin,Beller, Matthias
, p. 6116 - 6128 (2020/11/03)
The first general and efficient cobalt-catalyzed deoxygenative hydrogenation of amides to amines is presented. The optimal catalytic system based on a combination of [Co(NTf2)2] and (p-anisyl)triphos (L3) in the presence of [Me3SiOTf] as acidic co-catalyst facilitates the direct hydrogenation of a broad range of amides to the corresponding amines under mild conditions. A set of control experiments indicate that, after the initial reduction of the amide carboxylic group to the well-known hemiaminal intermediate, the reaction mainly proceeds through C-O bond cleavage though other pathways might be also involved to a minor extent. This journal is
Ru-Catalyzed Deoxygenative Transfer Hydrogenation of Amides to Amines with Formic Acid/Triethylamine
Pan, Yixiao,Luo, Zhenli,Xu, Xin,Zhao, Haoqiang,Han, Jiahong,Xu, Lijin,Fan, Qinghua,Xiao, Jianliang
supporting information, p. 3800 - 3806 (2019/07/12)
A ruthenium(II)-catalyzed deoxygenative transfer hydrogenation of amides to amines using HCO2H/NEt3 as the reducing agent is reported for the first time. The catalyst system consisting of [Ru(2-methylallyl)2(COD)], 1,1,1-tris(diphenylphosphinomethyl) ethane (triphos) and Bis(trifluoromethane sulfonimide) (HNTf2) performed well for deoxygenative reduction of various secondary and tertiary amides into the corresponding amines in high yields with excellent selectivities, and exhibits high tolerance toward functional groups including those that are reduction-sensitive. The choice of hydrogen source and acid co-catalyst is critical for catalysis. Mechanistic studies suggest that the reductive amination of the in situ generated alcohol and amine via borrowing hydrogen is the dominant pathway. (Figure presented.).
