6397-82-6Relevant articles and documents
Friedel-Crafts acylation of anisole with hexanoic acid catalyzed by Hβ zeolite-supported tungstophosphoric acid
Bai, Guoyi,Zhang, Huanhuan,Li, Tianyu,Dong, Huixian,Han, Jie
, p. 5041 - 5048 (2015)
Friedel-Crafts acylation of anisole with hexanoic acid was studied and an efficient method was established for the green synthesis of 4-methoxy phenyl hexyl ketone over an Hβ zeolite-supported tungstophosphoric acid catalyst (HPW/Hβ). The conversion of hexanoic acid was 100 % and the yield of 4-methoxy phenyl hexyl ketone reached 89.2 % under the optimized reaction conditions over HPW/Hβ, due to the synergistic effect between HPW and Hβ zeolite. Inductively coupled plasma results indicated the dealumination of the Hβ zeolite due to the treatment of tungstophosphoric acid (HPW), offering more active centers in HPW/Hβ. X-ray diffraction and Brunauer-Emmett-Teller results demonstrated that HPW was highly dispersed on the surface and in the larger pores of the Hβ zeolite. NH3 temperature-programmed desorption results showed HPW/Hβ has larger amounts of strongly acidic sites than the Hβ zeolite, accounting for its good catalytic performance. Furthermore, this catalyst can be recycled for four times with the yield of 4-methoxy phenyl hexyl ketone maintained at roughly 70 %, demonstrating its relatively good stability.
Iron-Catalyzed C-C Single-Bond Cleavage of Alcohols
Liu, Wei,Wu, Qiang,Wang, Miao,Huang, Yahao,Hu, Peng
supporting information, p. 8413 - 8418 (2021/11/01)
An iron-catalyzed deconstruction/hydrogenation reaction of alcohols through C-C bond cleavage is developed through photocatalysis, to produce ketones or aldehydes as the products. Tertiary, secondary, and primary alcohols bearing a wide range of substituents are suitable substrates. Complex natural alcohols can also perform the transformation selectively. A investigation of the mechanism reveals a procedure that involves chlorine radical improved O-H homolysis, with the assistance of 2,4,6-collidine.
AN IMPROVED AND COMMERCIALLY VIABLE PROCESS FOR PREPARATION OF ARYL KETONES
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Paragraph 0077; 0087, (2020/09/12)
The present disclosure provides a process for preparing an aryl ketone of Formula I, comprising reacting a substituted benzene of Formula II with a carboxylic acid of formula IIIa and/or a carboxylic anhydride of formula IIIb in presence of an alkyl sulfonic acid acting as catalyst cum solvent/contacting medium. I, II, IIIa, IIIb, wherein, R1, R2, R3 and R4 are as defined in the description.
Transition-Metal-Free Coupling of 1,3-Dipoles and Boronic Acids as a Sustainable Approach to C?C Bond Formation
Livingstone, Keith,Bertrand, Sophie,Kennedy, Alan R.,Jamieson, Craig
, p. 10591 - 10597 (2020/07/25)
The need for alternative, complementary approaches to enable C?C bond formation within organic chemistry is an on-going challenge in the area. Of particular relevance are transformations that proceed in the absence of transition-metal reagents. In the current study, we report a comprehensive investigation of the coupling of nitrile imines and aryl boronic acids as an approach towards sustainable C?C bond formation. In situ generation of the highly reactive 1,3-dipole facilitates a Petasis–Mannich-type coupling via a nucleophilic boronate complex. The introduction of hydrazonyl chlorides as a complementary nitrile imine source to the 2,5-tetrazoles previously reported by our laboratory further broadens the scope of the approach. Additionally, we exemplify for the first time the extension of this protocol into another 1,3-dipole, through the synthesis of aryl ketone oximes from aryl boronic acids and nitrile N-oxides.
Acylation of anisole with carboxylic acids catalyzed by tungsten oxide supported on titanium dioxide
Okumura, Kazu,Iida, Masaki,Yamashita, Hajime
, (2019/06/11)
Friedel-Crafts (F-C) acylation of anisole with octanoic acid was carried out on tungsten oxide (WO3) supported on various types of oxide supports. We have found that the highest activity was obtained when TiO2 was used as the support. WO3/TiO2 was found to be active in the acylation of anisole with carboxylic acids of varying alkyl chain lengths (C6–C10). It was possible to recycle the WO3/TiO2 catalyst for up to 5 times without deactivation. The turnover frequency (TOF) of the catalyst was closely correlated with the electronegativity of the cation of the support used for WO3. When a strong basic oxide such as CeO2 was used as a support, the acid strength of WO3 was diminished, while the strong acidity of WO3 was retained on a weak basic support like TiO2. This explains why the acid strength and consequently, the activity, were found to be the highest for the WO3/TiO2 catalyst. The trend of the catalytic performance was consistent with the order of acid strength of WO3 on different supports measured by temperature-programmed desorption of NH3.
Ketide compounds, method for manufacturing, and use for treating diabetes thereof
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Paragraph 0078; 0178-0181; 0231-0233, (2019/08/27)
The present invention relates to ketide compounds, as well as ketide compounds. The present invention relates to a method for preparing a ketide compound, and a use thereof, in which various anti-diabetic TMPA derivative designs can be induced, and is effective in comparison with existing multi-stage synthesis. In addition, the ketide compounds according to the present invention have strong AMPMPK activity and are expected to be useful as a therapeutic agent for diabetes. (by machine translation)
A Redox Strategy for Light-Driven, Out-of-Equilibrium Isomerizations and Application to Catalytic C-C Bond Cleavage Reactions
Ota, Eisuke,Wang, Huaiju,Frye, Nils Lennart,Knowles, Robert R.
supporting information, p. 1457 - 1462 (2019/01/25)
We report a general protocol for the light-driven isomerization of cyclic aliphatic alcohols to linear carbonyl compounds. These reactions proceed via proton-coupled electron-transfer activation of alcohol O-H bonds followed by subsequent C-C β-scission of the resulting alkoxy radical intermediates. In many cases, these redox-neutral isomerizations proceed in opposition to a significant energetic gradient, yielding products that are less thermodynamically stable than the starting materials. A mechanism is presented to rationalize this out-of-equilibrium behavior that may serve as a model for the design of other contrathermodynamic transformations driven by excited-state redox events.
Synthesis and catalytic reactivity in Friedel–Crafts acylations of monobridged bis(cyclopentadienyl)molybdenum(I) carbonyl complexes
Yan, Xin Long,Zhang, Ning,Hao, Zhi Qiang,Ma, Zhi Hong,Han, Zhan Gang,Zheng, Xue Zhong,Lin, Jin
, p. 75 - 79 (2018/04/11)
When the monobridged biscyclopentadienes (C5H5)R(C5H5) [R = C(CH3)2 (1), Si(CH3)2 (2), C(CH2)5 (3)] reacted with Mo(CO)6 in refluxing xylene, the corresponding complexes [(η5-C5H4)2R][Mo(CO)3]2 [R = C(CH3)2 (4), Si(CH3)2 (5), C(CH2)5 (6)] were obtained. These complexes were separated by chromatography and characterized by elemental analysis, IR, and 1H NMR spectroscopy. The molecular structures of 4 and 5 were determined by X-ray diffraction analysis. Friedel–Crafts acylation reactions of anisole derivatives with aromatic or aliphatic acyl chlorides catalyzed by complexes 4–6 showed that all of these monobridged bis(cyclopentadienyl)molybdenum carbonyl complexes have catalytic activity.
Syntheses, structures, and catalytic activity in Friedel–Crafts acylations of substituted tetramethylcyclopentadienyl molybdenum carbonyl complexes
Li, Tong,Yan, Xin-Long,Li, Zhan-Wei,Ma, Zhi-Hong,Li, Su-Zhen,Han, Zhan-Gang,Zheng, Xue-Zhong,Lin, Jin
, p. 313 - 322 (2018/02/22)
Reactions of the substituted tetramethylcyclopentadienes [C5HMe4R] [R?=?tBu, Ph, CH2CH2C(CH3)3] with Mo(CO)3(CH3CN)3 in refluxing xylene gave a series of dinuclear molybdenum carbonyl complexes [(η5-C5Me4R)Mo(CO)3]2 [R?=?tBu (1), Ph (2), CH2CH2C(CH3)3 (3)], [(η5-C5MetBu)Mo(μ-CO)2]2 (4)], and [(η5-C5Me4)tBu]2Mo2O4(μ-O) (5)], respectively. Complexes 1–5 were characterized by elemental analysis, IR, 1H NMR, and 13C NMR spectroscopy. In addition, their crystal structures were determined by X-ray crystal diffraction analysis. The catalytic activities of complexes 1–3 in Friedel–Crafts acylation in the presence of o-chloranil has also been investigated; the reactions were achieved under mild conditions to give the corresponding products in moderate yields.
Isolation and Characterization of Regioisomers of Pyrazole-Based Palladacycles and Their Use in α-Alkylation of Ketones Using Alcohols
Mamidala, Ramesh,Samser, Shaikh,Sharma, Nishant,Lourderaj, Upakarasamy,Venkatasubbaiah, Krishnan
supporting information, p. 3343 - 3351 (2017/09/18)
Regioisomers of 3,5-diphenyl-1-(4-(trifluoromethyl)phenyl)-1H-pyrazole-based palladacycles (1 and 2) were synthesized by the aromatic C-H bond activation of N/3-aryl ring. The application of these regioisomers as catalysts to enable the formation of α-alkylated ketones or quinolines with alcohols using a hydrogen borrowing process is evaluated. Experimental results reveal that palladacycle 2 is superior over palladacycle 1 to catalyze the reaction under similar reaction conditions. The reaction mechanisms for the palladacycles 1 and 2 catalyzed α-alkylation of acetophenone were studied using density functional theoretical (DFT) methods. The DFT studies indicate that palladacycle 2 has an energy barrier lower than that of palladacycle 1 for the alkylation reaction, consistent with the better catalytic activity of palladacycle 2 seen in the experiments. The palladacycle-phosphine system was found to tolerate a wide range of functional groups and serves as an efficient protocol for the synthesis of α-alkylated products under solvent-free conditions. In addition, the synthetic protocol was successfully applied to prepare donepezil, a drug for Alzheimer's disease, from simple starting materials.
