1116-76-3Relevant articles and documents
A multifaceted role of a mobile bismuth promoter in alcohol amination over cobalt catalysts
Bahri, Mounib,Ersen, Ovidiu,Khodakov, Andrei Y.,Kusema, Bright T.,Niu, Feng,Ordomsky, Vitaly V.,Yan, Zhen
, p. 4270 - 4278 (2020)
Promotion with small amounts of different elements is an efficient strategy for the enhancement of the performance of many heterogeneous catalysts. Supported cobalt catalysts exhibit significant activity in the synthesis of primary amines via alcohol amination with ammonia, which is an economically efficient and environmentally friendly process. Insufficient selectivity to primary amines, low activity and fast cobalt catalyst deactivation remain serious issues restricting the application of alcohol amination in the industry. In this work, we have discovered the multifaceted role of the bismuth promoter, which is highly mobile under reaction conditions, in 1-octanol amination over supported cobalt catalysts. First, the overall reaction rate was enhanced more than twice on promotion with bismuth. Second, the selectivity to primary amines increased 6 times in the presence of Bi at high alcohol conversion. Finally, the bismuth promotion resulted in extremely high stability of the cobalt catalyst. Characterization by XRD, temperature programmed reduction, STEM, CO chemisorption, BET, TGA and FTIR has showed that the enhancement of the catalytic performance on promotion with bismuth is due to better cobalt reducibility, easy removal of strongly adsorbed intermediates and products by the mobile promoter and suppression of amine coupling reactions resulting in secondary and tertiary amines.
Catalytic amination of octanol for synthesis of trioctylamine and catalyst characterization
Li, Yunling,Li, Qiuxiao,Zhi, Lifei,Zhang, Minghui
, p. 1635 - 1642 (2011)
Synthesis of trioctylamine by the amination of octanol and ammonia under atmospheric pressure over an excellent Ni-Cu catalyst supported on diatomite is studied in this article. The key factor for the synthesis is the preparation of catalyst with a high activity and selectivity. The activity and selectivity can be adjusted by varying the Ni to Cu ratios. The optimum molar ratio of Ni to Cu was 1.25:1. For the catalyst with a Ni/Cu ratio of 1.25:1, the conversion of octanol and the selectivity of trioctylamine reached 100 and 97.3%, respectively, at 5 h. The reaction of dioctylamine with octanol was the rate-determining step for the formation of trioctylamine. The Physical properties of catalysts, such as particle size, Brunauer-Emmett-Teller (BET) surface area, valence state of catalyst elements, morphology and reduction properties of catalysts were investigated by using X-ray diffraction, nitrogen adsorption-desorption isotherms (BET), X-ray photoelectron spectroscopy, Transmission electron microscopy, and temperature programmed reduction, respectively. The reaction scheme of catalytic amination of octanol with ammonia was discussed. Graphical Abstract: [Figure not available: see fulltext.][Figure not available: see fulltext.]
Highly Selective Hydrogenative Conversion of Nitriles into Tertiary, Secondary, and Primary Amines under Flow Reaction Conditions
Furugen, Chikara,Ito, Naoya,Jiang, Jing,Park, Kwihwan,Sajiki, Hironao,Shimizu, Eisho,Yamada, Tsuyoshi
, (2021/12/13)
Flow reaction methods have been developed to selectively synthesize tertiary, secondary, and primary amines depending on heterogeneous platinum-group metal species under catalytic hydrogenation conditions using nitriles as starting materials. A 10 % Pd/C-packed catalyst cartridge affords symmetrically substituted tertiary amines in good to excellent yields. A 10 % Rh/C-packed catalyst cartridge enables the divergent synthesis of secondary and primary amines, with either cyclohexane or acetic acid as a solvent, respectively. Reaction parameters, such as the metal catalyst, solvent, and reaction temperature, and continuous-flow conditions, such as flow direction and second support of the catalyst in a catalyst cartridge, are quite important for controlling the reaction between the hydrogenation of nitriles and nucleophilic attack of in situ-generated amines to imine intermediates. A wide variety of aliphatic and aromatic nitriles could be highly selectively transformed into the corresponding tertiary, secondary, and primary amines by simply changing the metal species of the catalyst or flow parameters. Furthermore, the selective continuous-flow methodologies are applied over at least 72 h to afford three different types of amines in 80–99 % yield without decrease in catalytic activities.
Direct Synthesis of Lactams from Keto Acids, Nitriles, and H2 by Heterogeneous Pt Catalysts
Siddiki,Touchy, Abeda S.,Bhosale, Ashvini,Toyao, Takashi,Mahara, Yuji,Ohyama, Junya,Satsuma, Atsushi,Shimizu, Ken-Ichi
, p. 789 - 795 (2018/02/27)
We report herein the first general catalytic system for the direct synthesis of N-substituted γ- and δ-lactams by reductive amination/cyclization of keto acids (including levulinic acid) with nitriles and H2 under mild conditions (7 bar H2, 110 °C, solvent free). The most effective catalyst, Pt and MoOx co-loaded TiO2 (Pt-MoOx/TiO2), shows a wide substrate scope, high turnover number (TON), and good reusability.