5071-96-5Relevant academic research and scientific papers
Studies on the synthesis, pungency and anti-biofouling performance of capsaicin analogues
Peng, Bixian,Wang, Junlian,Peng, Zhenghong,Zhou, Shengze,Wang, Fengqi,Ji, Yongliang,Ye, Zhangji,Zhou, Xiangfeng,Lin, Tong,Zhang, Xiaobin
, p. 435 - 442 (2012)
Ten capsaicin analogues were synthesized and their pungency degrees were determined through Scoville Organoleptic Test. The relationship between the structure and pungency degree of these capsaicin analogues was discussed. Then four of these capsaicin analogues with higher pungency degree were picked out and added to anti-biofouling paints as repellents to study their anti-biofouling performance by shallow sea buoyant raft hung-plate experimentation. The results showed that capsaicin and dihydrocapsaicin exhibited equally good anti-biofouling performance while nordihydrocapsaicin and N-vanillylnonanamide had poor anti-biofouling performance. Experimental results also showed that the paints with only 0.1% capsaicin or dihydrocapsaicin as repellent without any other biocides had also exhibited good anti-biofouling performance, which provided a new idea for developing novel, more environment-friendly and Cu 2O-free antifouling paints.
Method for preparing primary amine by catalytically reducing nitrile compounds through nano-porous palladium catalyst
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Paragraph 0077-0080, (2021/05/29)
The invention belongs to the technical field of heterogeneous catalysis, and provides a method for preparing primary amine by catalytically reducing nitrile compounds with a nano-porous palladium catalyst. According to the invention, aromatic and aliphatic nitrile compounds are adopted as raw materials, nano-porous palladium is adopted as a catalyst, ammonia borane is adopted as a hydrogen source, no additional additive is added, and selective hydrogenation is performed to prepare the corresponding primary amine. The method provided by the invention has the beneficial effects of mild reaction conditions, no additive, environmental protection, no need of hydrogen, simple operation, stable hydrogen source, safety, harmlessness, high conversion rate, high selectivity and good catalyst stability, and makes industrialization possible.
Cobalt-Catalyzed Hydrogenative Transformation of Nitriles
Zhang, Shaoke,Duan, Ya-Nan,Qian, Yu,Tang, Wenyue,Zhang, Runtong,Wen, Jialin,Zhang, Xumu
, p. 13761 - 13767 (2021/11/17)
Here, we report the transformation of nitrile compounds in a hydrogen atmosphere. Catalyzed by a cobalt/tetraphosphine complex, hydrogenative coupling of unprotected indoles with nitriles proceeds smoothly in a basic medium, yielding C3 alkylated indoles. In addition, the direct hydrogenation of nitriles under the same conditions yielded primary amines. Isotope labeling experiments, along with a series of control experiments, revealed a reaction pathway that involves nucleophilic addition of indoles and 1,4-reduction of a conjugate imine intermediate. Different from reductive alkylation of indoles under an acidic condition, E1cB elimination is believed to occur in this base-promoted hydrogenative coupling reaction.
Self-regulated catalysis for the selective synthesis of primary amines from carbonyl compounds
Fan, Xiaomeng,Gao, Jin,Gao, Mingxia,Jia, Xiuquan,Ma, Jiping,Xu, Jie
supporting information, p. 7115 - 7121 (2021/09/28)
Most current processes for the general synthesis of primary amines by reductive amination are performed with enormously excessive amounts of hazardous ammonia. It remains unclear how catalysts should be designed to regulate amination reaction dynamics at a low ammonia-to-substrate ratio for the quantitative synthesis of primary amines from the corresponding carbonyl compounds. Herein we show a facile control of the reaction selectivity in the layered boron nitride supported ruthenium catalyzed reductive amination reaction. Specifically, locating ruthenium to the edge surface of layered boron nitride leads to an increased hydrogenation activity owing to the enhanced interfacial electronic effects between ruthenium and the edge surface of boron nitride. This enables self-accelerated reductive amination reactions which quantitatively synthesize structurally diverse primary amines by reductive amination of carbonyl compounds with twofold ammonia. This journal is
Ultra-small cobalt nanoparticles from molecularly-defined Co-salen complexes for catalytic synthesis of amines
Beller, Matthias,Chandrashekhar, Vishwas G.,Gawande, Manoj B.,Jagadeesh, Rajenahally V.,Kalevaru, Narayana V.,Kamer, Paul C. J.,Senthamarai, Thirusangumurugan,Zbo?il, Radek
, p. 2973 - 2981 (2020/03/27)
We report the synthesis of in situ generated cobalt nanoparticles from molecularly defined complexes as efficient and selective catalysts for reductive amination reactions. In the presence of ammonia and hydrogen, cobalt-salen complexes such as cobalt(ii)-N,N′-bis(salicylidene)-1,2-phenylenediamine produce ultra-small (2-4 nm) cobalt-nanoparticles embedded in a carbon-nitrogen framework. The resulting materials constitute stable, reusable and magnetically separable catalysts, which enable the synthesis of linear and branched benzylic, heterocyclic and aliphatic primary amines from carbonyl compounds and ammonia. The isolated nanoparticles also represent excellent catalysts for the synthesis of primary, secondary as well as tertiary amines including biologically relevant N-methyl amines.
Nitrile Synthesis by Aerobic Oxidation of Primary Amines and in situ Generated Imines from Aldehydes and Ammonium Salt with Grubbs Catalyst
Utsumi, Tatsuki,Noda, Kenta,Kawauchi, Daichi,Ueda, Hirofumi,Tokuyama, Hidetoshi
, p. 3583 - 3588 (2020/08/05)
Herein, a Grubbs-catalyzed route for the synthesis of nitriles via the aerobic oxidation of primary amines is reported. This reaction accommodates a variety of substrates, including simple primary amines, sterically hindered β,β-disubstituted amines, allylamine, benzylamines, and α-amino esters. Reaction compatibility with various functionalities is also noted, particularly with alkenes, alkynes, halogens, esters, silyl ethers, and free hydroxyl groups. The nitriles were also synthesized via the oxidation of imines generated from aldehydes and NH4OAc in situ. (Figure presented.).
Method for preparing primary amines through hydrogen transfer selective nitrile reduction
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Paragraph 0052-0056, (2019/05/02)
The invention discloses a method for preparing primary amines through hydrogen transfer selective nitrile reduction. The method includes the step of adding low-price copper, iron and other metal saltsor low-price easy-to-obtain iodine elementary substances as additives with a nitrile compound as the raw material and oxazole borane as the hydrogen transfer agent under the mild conditions, therebypromoting the hydrogen transfer reaction and selectively synthesizing a series of corresponding primary amines under different conditions respectively. The high yield and high selectivity are achievedin the reaction. The oxazole borane is obtained through reaction of alkamine and a tetrahydrofuran complex of borane. In addition, the method is mild in reaction condition, easy to operate, free of high-pressure devices, environmentally friendly and high in raw material general applicability, the agents required for the reaction are all low in price and easy to obtain, the reduction product is only primary amines, and selectivity and repeatability are high. Thus, an effective scheme is provided for the industrial production of other high-additional-value compounds of similar structures in future.
Mild palladium-catalysed highly efficient hydrogenation of CN, C-NO2, and CO bonds using H2 of 1 atm in H2O
Liu, Yaxu,He, Shaopo,Quan, Ziyi,Cai, Huizhuo,Zhao, Yang,Wang, Bo
supporting information, p. 830 - 838 (2019/02/27)
Here we present the first example of a mild and high-efficiency protocol enabling a process in water using 1 atm of H2 for the efficient and selective hydrogenation of nitriles, nitro compounds, ketones, and aldehydes to yield primary amines and alcohols with satisfactory yields of up to >99%. Several palladium-based nanoparticle catalysts were prepared from K2PdCl4 and ligands, and one of them was found to be the best and most suitable for the hydrogenation of CN, C-NO2, and CO bonds. In addition, the catalyst Pd-NPs can be easily recycled and reused without losing their activity and selectivity. A plausible mechanism for the hydrogenation of a CN bond was also proposed, representing the first example that possesses great potential for sustainable industrial purposes.
A ppm level Rh-based composite as an ecofriendly catalyst for transfer hydrogenation of nitriles: Triple guarantee of selectivity for primary amines
Liu, Lei,Li, Jifan,Ai, Yongjian,Liu, Yuhong,Xiong, Jialiang,Wang, Hongdong,Qiao, Yijun,Liu, Wenrui,Tan, Shanchao,Feng, Shaofei,Wang, Kunpeng,Sun, Hongbin,Liang, Qionglin
, p. 1390 - 1395 (2019/03/26)
Hydrogenation of nitriles to afford amines under mild conditions is a challenging task with an inexpensive heterogeneous catalyst, and it is even more difficult to obtain primary amines selectively because of the accompanying self-coupling side reactions. An efficient catalytic system was designed as Fe3O4@nSiO2-NH2-RhCu@mSiO2 to prepare primary amines through the transfer hydrogenation of nitrile compounds with economical HCOOH as the hydrogen donor. The loading of rhodium in the catalyst could be at the ppm level, and the TOF reaches 6803 h-1 for Rh. This catalytic system has a wide substrate range including some nitriles that could not proceed in the previous literature. The experimental results demonstrate that the excellent selectivity for primary amines is guaranteed by three tactics, which are the strong active site, the inhibition of side products by the hydrogen source and the special pore structure of the catalyst. In addition, the catalyst could be reused ten times without activity loss through convenient magnetic recovery.
Highly efficient nitrobenzene and alkyl/aryl azide reduction in stainless steel jars without catalyst addition
Martina, Katia,Baricco, Francesca,Tagliapietra, Silvia,Moran, Maria Jesus,Cravotto, Giancarlo,Cintas, Pedro
supporting information, p. 18881 - 18888 (2018/11/26)
The mechanochemical and selective reduction of aryl nitro and aryl/alkyl azide derivatives, with either formate salts or hydrazine, to the corresponding, synthetically useful amines occurs in excellent yields in a planetary ball mill without the addition of a catalyst. This newly developed and solvent-free protocol is efficient, fast and does not require the addition of a metal hydrogenation catalyst as the stainless steel jar itself fulfils that role. The method has been applied to a broad range of compounds and excellent yields have been obtained. The formylation of alkyl amines has been successfully performed, by means of mechanochemical activation, in the presence of ammonium formate alone.
