35923-45-6Relevant academic research and scientific papers
Aerobic oxygenation of α-methylene ketones under visible-light catalysed by a CeNi3complex with a macrocyclic tris(salen)-ligand
Fujiwara, Sakiko,Kon, Yoshihiro,Mashima, Kazushi,Nagae, Haruki,Okuda, Jun,Sakamoto, Kazutaka,Sato, Kazuhiko,Schindler, Tobias
supporting information, p. 11169 - 11172 (2021/11/04)
A hetero-tetranuclear CeNi3 complex with a macrocyclic ligand catalysed the aerobic oxygenation of a methylene group adjacent to a carbonyl group under visible-light radiation to produce the corresponding α-diketones. The visible-light induced homolysis of the Ce-O bond of a bis(enolate) intermediate is proposed prior to aerobic oxygenation.
Catalyst-Free and Transition-Metal-Free Approach to 1,2-Diketones via Aerobic Alkyne Oxidation
Shen, Duyi,Wang, Hongyan,Zheng, Yanan,Zhu, Xinjing,Gong, Peiwei,Wang, Bin,You, Jinmao,Zhao, Yulei,Chao, Mianran
, p. 5354 - 5361 (2021/05/05)
A catalyst-free and transition-metal-free method for the synthesis of 1,2-diketones from aerobic alkyne oxidation was reported. The oxidation of various internal alkynes, especially more challenging aryl-alkyl acetylenes, proceeded smoothly with inexpensive, easily handled, and commercially available potassium persulfate and an ambient air balloon, achieving the corresponding 1,2-diketones with up to 85% yields. Meanwhile, mechanistic studies indicated a radical process, and the two oxygen atoms in the 1,2-diketons were most likely from persulfate salts and molecular oxygen, respectively, rather than water.
Lanthanide complexes based on an anthraquinone derivative ligand and applications as photocatalysts for visible-light driving photooxidation reactions
Zhu, Ting-Ting,Tao, Yu-Tong,Sun, Yue,Wang, Xue,Zhang, Xiao-Wen,Chai, Jia-Lu,Han, Jie,Zhao, Xiao-Li,Chen, Xu-Dong
, (2021/04/05)
Four isostructural lanthanide coordination complexes based on 3,7-diamino-9,10-anthraquinone-2,6-disulfonate (dianionic, L) have been synthesized by hydrothermal method, namely [Er(L)(H2O)6]?[Er(H2O)8]?2L?8H2O (Er-L), [Tm(L)(H2O)6]?[Tm(H2O)8]?2L?8.5H2O (Tm-L), [Yb(L)(H2O)6]?[Yb(H2O)8]?2L?9H2O (Yb-L), [Lu(L)(H2O)6]?[Lu(H2O)8]?2L?9H2O (Lu-L). Single-crystal X-ray analysis reveals the existence of both coordinated and free ligand L in the crystal structure. Versatile sulfonate groups on these distinct L ligands, together with very rich coordinated and lattice water molecules, form a lot of hydrogen-bonding motifs that contribute to the stabilization of the crystal packing. It is interesting that the ligands stack into columns through strong π-π interactions and the centroid-centroid distances are between 3.281 and 3.331 ?. These ligands are stacked in an alternate off-set mode to avoid the steric hindrance between the bulky sulfonate groups, generating a repeated structural unit involving six stacked ligands. These lanthanide complexes proved to be good heterogeneous photocatalyst for promoting the visible-light driving photooxidation reactions of diarylacetylenes and thioethers. The Er-L complex exhibited the best catalytic activity and showed good catalytic efficiency over a wide range of substrates for both reaction systems. The Er-L photocatalyst can be easily isolated by simple filtration as crystalline material upon completion of the photooxidation reaction without structure change, and can be recycled for at least five catalytic cycles with persistent catalytic efficiency without any need of activation or regeneration. This family of lanthanide complexes represent a category of promising heterogeneous photocatalysts in terms of green chemistry, with the potential of promoting organic transformations highly efficiently under the irradiation of visible light.
One-pot cascade synthesis of α-diketones from aldehydes and ketones in water by using a bifunctional iron nanocomposite catalyst
Song, Tao,Zhou, Xin,Wang, Xiaoxue,Xiao, Jianliang,Yang, Yong
supporting information, p. 1955 - 1959 (2021/03/26)
A new methodology for the synthesis of α-diketones was reportedviaa one-pot cascade process from aldehydes and ketones catalyzed by a bifunctional iron nanocomposite using H2O2as a green oxidant in water. The one-pot strategy showed excellent catalytic stability, comprehensive suitability of substrates and important practical utility for directly synthesizing biologically active and medicinally valuable N-heterocyclesviaan intermittent process.
Rhodium-Catalyzed Aerobic Decomposition of 1,3-Diaryl-2-diazo-1,3-diketones: Mechanistic Investigation and Application to the Synthesis of Benzils
Zhu, Jia-Liang,Tsai, Yi-Ting
, p. 813 - 828 (2020/12/22)
The conversion of 1,3-diaryl-2-diazo-1,3-diketones to 1,2-daryl-1,2-diketones (benzils) is reported based on a rhodium(II)-catalyzed aerobic decomposition process. The reaction occurs at ambient temperatures and can be catalyzed by a few dirhodium carboxylates (5 mol %) under a balloon pressure of oxygen. Moreover, an oxygen atom from the O2 reagent is shown to be incorporated into the product, and this is accompanied by the extrusion of a carbonyl unit from the starting materials. Mechanistically, it is proposed that the decomposition may proceed via the interaction of a ketene intermediate resulting from a Wolff rearrangement of the carbenoid, with a rhodium peroxide or peroxy radical species generated upon the activation of molecular oxygen. The proposed mechanism has been supported by the results from a set of controlled experiments. By using this newly developed strategy, a large array of benzil derivatives as well as 9,10-phenanthrenequinone were synthesized from the corresponding diazo substrates in varying yields. On the other hand, the method did not allow the generation of benzocyclobutene-1,2-dione from 2-diazo-1,3-indandione because of the difficulty of inducing the initial rearrangement.
Synthesis of unsymmetrical benzilsviapalladium-catalysed a-arylation-oxidation of 2-hydroxyacetophenones with aryl bromides
Matsuda, Takanori,Oyama, Souta
supporting information, p. 3679 - 3683 (2020/06/03)
A diverse set of unsymmetrically substituted benzils were facilely synthesised by a cross-coupling reaction between 2-hydroxyacetophenones and aryl bromides in the presence of a palladium catalyst. Experimental studies suggested a reaction mechanism involving a one-pot tandem palladium-catalysed a-arylation and oxidation, where aryl bromides play a dual role as mild oxidants as well as arylating agents.
Visible light-induced aerobic oxidation of diarylalkynes to α-diketones catalyzed by copper-superoxo at room temperature
Charpe, Vaibhav Pramod,Hwang, Kuo Chu,Sagadevan, Arunachalam
supporting information, p. 4426 - 4432 (2020/08/10)
We have developed the visible light induced simple copper(ii) chloride catalyzed oxidation of diarylacetylenes to α-diketones by molecular oxygen at room temperature. The in situ generated copper(ii)-superoxo complex is a light-absorbing species that oxidizes inert diarylacetylenes to α-diketones. In contrast to reported photochemical processes, the current oxidation protocol does not require any exogenous photocatalyst or radical initiator. The green chemistry metrics evaluation signifies that the E-factor for the current oxidation process is ~2.3 times better than that of reported photochemical processes. The current reaction scores 63 on the EcoScale of 0-100, indicating an adequate synthesis process. Thus, the overall oxidation process is simple, environmentally benign, and economically feasible. This journal is
A Bifunctional Iron Nanocomposite Catalyst for Efficient Oxidation of Alkenes to Ketones and 1,2-Diketones
Ma, Zhiming,Ren, Peng,Song, Tao,Xiao, Jianliang,Yang, Yong,Yuan, Youzhu
, p. 4617 - 4629 (2020/05/19)
We herein report the fabrication of a bifunctional iron nanocomposite catalyst, in which two catalytically active sites of Fe-Nx and Fe phosphate, as oxidation and Lewis acid sites, were simultaneously integrated into a hierarchical N,P-dual doped porous carbon. As a bifunctional catalyst, it exhibited high efficiency for direct oxidative cleavage of alkenes into ketones or their oxidation into 1,2-diketones with a broad substrate scope and high functional group tolerance using TBHP as the oxidant in water under mild reaction conditions. Furthermore, it could be easily recovered for successive recycling without appreciable loss of activity. Mechanistic studies disclose that the direct oxidation of alkenes proceeds via the formation of an epoxide as intermediate followed by either acid-catalyzed Meinwald rearrangement to give ketones with one carbon shorter or nucleophilic ring-opening to generate 1,2-diketones in a cascade manner. This study not only opens up a fancy pathway in the rational design of Fe-N-C catalysts but also offers a simple and efficient method for accessing industrially important ketones and 1,2-diketones from alkenes in a cost-effective and environmentally benign fashion.
Rate Enhancement in CAN-Promoted Pd(PPh3)2Cl2-Catalyzed Oxidative Cyclization: Synthesis of 2-Ketofuran-4-carboxylate Esters
Ruengsangtongkul, Sureeporn,Chaisan, Nattawadee,Thongsornkleeb, Charnsak,Tummatorn, Jumreang,Ruchirawat, Somsak
, p. 2514 - 2517 (2019/04/30)
Stoichiometric ceric ammonium nitrate (CAN) and a catalytic amount of Pd(PPh3)2Cl2 (5 mol %) can rapidly produce multisubstituted 2-ketofuran-4-carboxylate esters from 2-propargylic 1,3-ketoesters via oxidative O-cyclization reaction. Pd(PPh3)2Cl2 was found to be the crucial catalyst as its inclusion greatly enhanced the rate of the reaction and cleanly afforded the products within minutes. Over 30 substrates were successfully converted to the desired compounds in mostly moderate to good yields.
ICl/AgNO3 Co-catalyzed radical oxidation of diaryl- A nd alkylarylalkynes into 1,2-diketones
Yang, Wen,Chen, Yu,Yao, Yongqi,Yang, Xin,Lin, Qifu,Yang, Dingqiao
, p. 11080 - 11090 (2019/09/09)
A novel ICl/AgNO3 co-catalyzed radical oxidation of diaryl- A nd alkylarylalkynes into 1,2-diketones is reported. The reaction proceeded smoothly under mild conditions and generated 1,2-diketones in moderate to good yields with a good tolerance of functional groups. Furthermore, the obtained C4-(1,2-diketoaryl)isoxazoles could react smoothly with 1,2-diaminobenzene to form C4-(3-arylquinoxalin-2-yl)isoxazoles. At last, a new one-pot strategy for the synthesis of quinoxalines from 1,2-diphenylethynes and 1,2-diaminobenzene is also reported.
