Xn:Harmful;
71-41-0Relevant academic research and scientific papers
Free radical alkylation of the remote nonactivated δ-carbon atom
Petrovi?, Goran,?ekovi?, ?ivorad
, p. 627 - 630 (1997)
A free radical introduction of functionalized alkyl chains into the δ-carbon atom (Michael type alkylation) of alkyl nitrites and alkyl benzenesulfenic-O-esters was achieved.
MOF-derived hcp-Co nanoparticles encapsulated in ultrathin graphene for carboxylic acids hydrogenation to alcohols
Dong, Mei,Fan, Weibin,Gao, Xiaoqing,Zhu, Shanhui
, p. 201 - 211 (2021/06/03)
Highly efficient conversion of carboxylic acids to valuable alcohols is a great challenge for easily corroded non-noble metal catalysts. Here, a series of few-layer graphene encapsulated metastable hexagonal closed-packed (hcp) Co nanoparticles were fabricated by reductive pyrolysis of metal-organic framework precursor. The sample pyrolyzed at 400 °C (hcp-Co@G400) presented outstanding performance and stability for converting a variety of functional carboxylic acids and its turnover frequency was one magnitude higher than that of conventional facc-centered cubic (fcc) Co catalysts. In situ DRIFTS spectroscopy of model reaction acetic acid hydrogenation and DFT calculation results confirm that carboxylic acid initially undergoes dehydroxylation to RCH2CO* followed by consecutive hydrogenation to RCH2CH2OH through RCH2COH*. Acetic acid prefers to vertically adsorb at hcp-Co (0 0 2) facet with a much lower adsorption energy than parallel adsorption at fcc-Co (1 1 1) surface, which plays a key role in decreasing the activation barrier of the rate-determining step of acetic acid dehydroxylation.
Discovery of Anti-TNBC Agents Targeting PTP1B: Total Synthesis, Structure-Activity Relationship, in Vitro and in Vivo Investigations of Jamunones
Hu, Caijuan,Li, Guoxun,Mu, Yu,Wu, Wenxi,Cao, Bixuan,Wang, Zixuan,Yu, Hainan,Guan, Peipei,Han, Li,Li, Liya,Huang, Xueshi
supporting information, p. 6008 - 6020 (2021/05/06)
Twenty-three natural jamunone analogues along with a series of jamunone-based derivatives were synthesized and evaluated for their inhibitory effects against breast cancer (BC) MDA-MB-231 and MCF-7 cells. The preliminary structure-activity relationship revealed that the length of aliphatic side chain and free phenolic hydroxyl group at the scaffold played a vital role in anti-BC activities and the methyl group on chromanone affected the selectivity of molecules against MDA-MB-231 and MCF-7 cells. Among them, jamunone M (JM) was screened as the most effective anti-triple-negative breast cancer (anti-TNBC) candidate with a high selectivity against BC cells over normal human cells. Mechanistic investigations indicated that JM could induce mitochondria-mediated apoptosis and cause G0/G1 phase arrest in BC cells. Furthermore, JM significantly restrained tumor growth in MDA-MB-231 xenograft mice without apparent toxicity. Interestingly, JM could downregulate phosphatidylinositide 3-kinase (PI3K)/Akt pathway by suppressing protein-tyrosine phosphatase 1B (PTP1B) expression. These findings revealed the potential of JM as an appealing therapeutic drug candidate for TNBC.
METHOD FOR PRODUCING BIO ALCOHOL FROM INTERMEDIATE PRODUCTS OF ANAEROBIC DIGESTION TANK
-
Paragraph 0057-0060; 0063; 0065-0066; 0068-0069; 0071, (2021/05/25)
The present invention relates to a method for producing a bio-alcohol by reacting a mixture of volatile fatty acid with methanol in 2 through 11 in a reactor in the presence of a 280 °C-membered alkaline earth metal catalyst or 400 °C transition metal catalyst formed based on a support.
Chromium-Catalyzed Production of Diols From Olefins
-
Paragraph 0111, (2021/03/19)
Processes for converting an olefin reactant into a diol compound are disclosed, and these processes include the steps of contacting the olefin reactant and a supported chromium catalyst comprising chromium in a hexavalent oxidation state to reduce at least a portion of the supported chromium catalyst to form a reduced chromium catalyst, and hydrolyzing the reduced chromium catalyst to form a reaction product comprising the diol compound. While being contacted, the olefin reactant and the supported chromium catalyst can be irradiated with a light beam at a wavelength in the UV-visible spectrum. Optionally, these processes can further comprise a step of calcining at least a portion of the reduced chromium catalyst to regenerate the supported chromium catalyst.
Disproportionation of aliphatic and aromatic aldehydes through Cannizzaro, Tishchenko, and Meerwein–Ponndorf–Verley reactions
Sharifi, Sina,Sharifi, Hannah,Koza, Darrell,Aminkhani, Ali
, p. 803 - 808 (2021/07/20)
Disproportionation of aldehydes through Cannizzaro, Tishchenko, and Meerwein–Ponndorf–Verley reactions often requires the application of high temperatures, equimolar or excess quantities of strong bases, and is mostly limited to the aldehydes with no CH2 or CH3 adjacent to the carbonyl group. Herein, we developed an efficient, mild, and multifunctional catalytic system consisting AlCl3/Et3N in CH2Cl2, that can selectively convert a wide range of not only aliphatic, but also aromatic aldehydes to the corresponding alcohols, acids, and dimerized esters at room temperature, and in high yields, without formation of the side products that are generally observed. We have also shown that higher AlCl3 content favors the reaction towards Cannizzaro reaction, yet lower content favors Tishchenko reaction. Moreover, the presence of hydride donor alcohols in the reaction mixture completely directs the reaction towards the Meerwein–Ponndorf–Verley reaction. Graphic abstract: [Figure not available: see fulltext.].
Ruthenium (II) complexes with C2- and C1-symmetric bis-(+)-camphopyrazole ligands and their evaluation in catalytic transfer hydrogenation of aldehydes
Agrifoglio, Giuseppe,Blanco, Christian O.,Dorta, Romano,Herrera, Alberto,Landaeta, Vanessa R.,Llovera, Ligia,Pastrán, Jesús,Venuti, Doménico
supporting information, (2021/05/10)
Ruthenium (II) piano-stool complexes with bis-(+)-camphopyrazole ligands of C2 and C1 symmetry were prepared in good yields (66–98%). New C2-C1 ligands and complexes were characterized by multinuclear NMR spectroscopy, FT-IR and elemental analysis. The catalytic performance of the Ru(II)-bis-(+)-camphopyrazole complexes in the transfer hydrogenation of benzaldehyde and valeraldehyde using isopropanol/potassium carbonate and formic acid/triethylamine mixtures as hydrogen donors, was evaluated, resulting in moderate yields (>54%) for the reduction to the desired primary alcohols. The system with isopropanol as hydrogen source proved to be more selective than the analogous system using the azeotropic formic acid/triethylamine mixture, allowing benzyl alcohol to be obtained in quantitative yield (>99%) for a particular catalyst precursor. Furthermore, complexes with C2 symmetry ligands showed higher yields than those with C1 symmetry ligands in all of the evaluated systems.
Role of Ga3+promoter in the direct synthesis of iso-butanolviasyngas over a K-ZnO/ZnCr2O4catalyst
Zhang, Tao,Zeng, Chunyang,Wu, Yingquan,Gong, Nana,Yang, Jiaqian,Yang, Guohui,Tsubaki, Noritatsu,Tan, Yisheng
, p. 1077 - 1088 (2021/02/26)
The direct synthesis of iso-butanol is an important reaction in syngas (composed of CO and H2) conversion. K-ZnO/ZnCr2O4(K-ZnCr) is a commonly used catalyst. Here, Ga3+is used as an effective promoter to boost the efficiency of the catalyst and retard the production of CO2. X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflection spectroscopy and electron microscopy were used to characterize the structural variations with different amounts of Ga3+, the results showed that the particle size of the catalyst decreases with the addition of Ga3+. The temperature-programmed desorption of NH3and CO2, and diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTs) analysis of the CO adsorption revealed that the acidity and basicity were altered owing to the different forms of Ga3+adoption. X-ray photoelectron spectroscopy and density functional theory (DFT) calculations revealed that the formation of Ga clusters that are coordinated on the exposed surfaces of ZnCr2O4, and undergo a tetra-coordinated Ga3+exchange with one of the Zn in ZnCr2O4(ZG) and ZnGa2O4, probably depends on the amount of Ga added. The structural evolution of the Ga3+promoted K-ZnO/ZnCr2O4catalysts can be described as follows: (i) the main forms are ZG and Ga coordinated ZnCr2O4, in which the amount of Ga3+is below 1.10 wt%; and (ii) the Ga3+containing compound is gradually changed from ZG to ZnGa2O4and the amount of gallium clusters increased when the amount of Ga3+was higher than 1.10 wt%. The catalytic performance evaluation results show that K-Ga1.10ZnCr exhibits the highest space time yield and selectivity of alcohols, in which the three compounds play different roles in syngas conversion: ZG is the main active site that boosts the efficiency of the catalysts, owing to the intensified CO adsorption and decreased activation energy of CHO formation through CO hydrogenation; ZnGa2O4only modifies the surface basicity and acidity on the catalyst, thereby impacting the carbon chain growth after the CO is adsorbed. The effects of Ga coordinated with ZnCr2O4shows little impact on the CO adsorption owing to the weak electron donating effects of Ga.
Effect of second metal component on the reduction property and catalytic performance of NiO-MOx/Nb2O5-TiO2 for direct synthesis of 2-propylheptanol from n-valeraldehyde
An, Hualiang,Wang, Yanji,Zhao, Lili,Zhao, Xinqiang
, (2020/11/02)
In order to improve the catalytic performance of NiO/Nb2O5-TiO2, several kinds of the second metal oxide component MOx (M = Pd, Co, Ir or Rh) were separately introduced and their effects on the reduction propert
Effect of Ni/Co mass ratio and NiO-Co3O4loading on catalytic performance of NiO-Co3O4/Nb2O5-TiO2for direct synthesis of 2-propylheptanol from n -valeraldehyde
Zhao, Lili,An, Hualiang,Zhao, Xinqiang,Wang, Yanji
, p. 1736 - 1742 (2021/01/20)
In the direct synthesis of 2-propylheptanol (2-PH) from n-valeraldehyde, a second-metal oxide component Co3O4 was introduced into NiO/Nb2O5-TiO2 catalyst to assist in the reduction of NiO. In order to optimize the catalytic performance of NiO-Co3O4/Nb2O5-TiO2 catalyst, the effects of the Ni/Co mass ratio and NiO-Co3O4 loading were investigated. A series of NiO-Co3O4/Nb2O5-TiO2 catalysts with different Ni/Co mass ratios were prepared by the co-precipitation method and their catalytic performances were evaluated. The result showed that NiO-Co3O4/Nb2O5-TiO2 with a Ni/Co mass ratio of 8/3 demonstrated the best catalytic performance because the number of d-band holes in this catalyst was nearly equal to the number of electrons transferred in hydrogenation reaction. Subsequently, the NiO-Co3O4/Nb2O5-TiO2 catalysts with different Ni/Co mass ratios were characterized by XRD and XPS and the results indicated that both an interaction of Ni with Co and formation of a Ni-Co alloy were the main reasons for the reduction of NiO-Co3O4/Nb2O5-TiO2 catalyst in the reaction process. A higher NiO-Co3O4 loading could increase the catalytic activity but too high a loading resulted in incomplete reduction of NiO-Co3O4 in the reaction process. Thus the NiO-Co3O4/Nb2O5-TiO2 catalyst with a Ni/Co mass ratio of 8/3 and a NiO-Co3O4 loading of 14 wt% showed the best catalytic performance; a 2-PH selectivity of 80.4% was achieved with complete conversion of n-valeraldehyde. Furthermore, the NiO-Co3O4/Nb2O5-TiO2 catalyst showed good stability. This was ascribed to the interaction of Ni with Co, the formation of the Ni-Co alloy and further reservation of both in the process of reuse.
