779-90-8Relevant academic research and scientific papers
Coordination preferences of 4-dimethylaminobut-3-en-2-one in thermally and photochemically activated reactions with Ru3(CO)12
Osintseva, Svetlana V.,Shtel'tser, Nikolay A.,Peregudov, Alexander S.,Kreindlin, Arkadii Z.,Dolgushin, Fedor M.
, p. 147 - 160 (2018)
The thermally and photochemically activated reactions of Ru3(CO)12 with 4-dimethylaminobut-3-en-2-one (L) were studied and several mononuclear and polynuclear products were isolated and fully characterized by a combination of spectro
Selective electrochemical oxidation of aromatic hydrocarbons and preparation of mono/multi-carbonyl compounds
Li, Zhibin,Zhang, Yan,Li, Kuiliang,Zhou, Zhenghong,Zha, Zhenggen,Wang, Zhiyong
, p. 2134 - 2141 (2021/09/29)
A selective electrochemical oxidation was developed under mild condition. Various mono-carbonyl and multi-carbonyl compounds can be prepared from different aromatic hydrocarbons with moderate to excellent yield and selectivity by virtue of this electrochemical oxidation. The produced carbonyl compounds can be further transformed into α-ketoamides, homoallylic alcohols and oximes in a one-pot reaction. In particular, a series of α-ketoamides were prepared in a one-pot continuous electrolysis. Mechanistic studies showed that 2,2,2-trifluoroethan-1-ol (TFE) can interact with catalyst species and generate the corresponding hydrogen-bonding complex to enhance the electrochemical oxidation performance. [Figure not available: see fulltext.]
Iron-catalyzed trimerization of terminal alkynes enabled by pyrimidinediimine ligands: A regioselective method for the synthesis of 1,3,5-substituted arenes
Doll, Julianna S.,Eichelmann, Robert,Hertwig, Leif E.,Bender, Thilo,Kohler, Vincenz J.,Bill, Eckhard,Wadepohl, Hubert,Ro?ca, Drago?-Adrian
, p. 5593 - 5600 (2021/05/31)
The development of pyrimidine-based analogues of the well-known pyridinediimine (PDI) iron complexes enables access to a functional-group-tolerant methodology for the catalytic trimerization of terminal aliphatic alkynes. Remarkably, in contrast to established alkyne trimerization protocols, the 1,3,5-substituted arenes are the main reaction products. Preliminary mechanistic investigations suggest that the enhanced π-acidity of the pyrimidine ring, combined with the hemilability of the imine groups coordinated to the iron center, facilitates this transformation. The entry point in the catalytic cycle is an isolable iron dinitrogen complex. The catalytic reaction proceeds via a 1,3-substituted metallacycle, which explains the observed 1,3,5-regioselectivity. Such a metallacycle could be isolated and represents a rare 1,3-substituted ferracycle obtained through alkyne cycloaddition.
Light and oxygen-enabled sodium trifluoromethanesulfinate-mediated selective oxidation of C-H bonds
Fu, Hua,Liu, Can,Liu, Yong,Yang, Haijun,Zhu, Xianjin
supporting information, p. 4357 - 4363 (2020/07/14)
Visible light-induced organic reactions are important chemical transformations in organic chemistry, and their efficiency highly depends on suitable photocatalysts. However, the commonly used photocatalysts are precious transition-metal complexes and elaborate organic dyes, which hamper large-scale production due to high cost. Here, for the first time, we report a novel strategy: light and oxygen-enabled sodium trifluoromethanesulfinate-mediated selective oxidation of C-H bonds, allowing high-value-added aromatic ketones and carboxylic acids to be easily prepared in high-to-excellent yields using readily available alkyl arenes, methyl arenes and aldehydes as materials. The mechanistic investigations showed that the treatment of inexpensive and readily available sodium trifluoromethanesulfinate with oxygen under irradiation of light could in situ form a pentacoordinate sulfide intermediate as an efficient photosensitizer. The method represents a highly efficient, economical and environmentally friendly strategy, and the light and oxygen-enabled sodium trifluoromethanesulfinate photocatalytic system represents a breakthrough in photochemistry. This journal is
Cyclotrimerization of alkynes catalyzed by a self-supported cyclic tri-nuclear nickel(0) complex with α-diimine ligands
Shen, Lingyi,Zhao, Yanxia,Luo, Qiong,Li, Qian-Shu,Liu, Bin,Redshaw, Carl,Wu, Biao,Yang, Xiao-Juan
supporting information, p. 4643 - 4649 (2019/04/05)
A cyclic tri-nuclear α-diimine nickel(0) complex [{Ni(μ-LMe-2,4)}3] (2) was synthesized from a “pre-organized”, trimerized trigonal LNiBr2-type precursor [Ni3(μ2-Br)3(μ3-Br)2(LMe-2,4)3]·Br (1; LMe-2,4 = [(2,4-Me2C6H3)NC(Me)]2). In complex 2, the α-diimine ligands not only exhibit the normal N,N′-chelating mode, but they also act as bridges between the Ni atoms through an unusual π-coordination of a C═N bond to Ni. Complex 2 is able to catalyze the cyclotrimerization of alkynes to form substituted benzenes in good yield and regio-selectivity for the 1,3,5-isomers, which is found to vary with the nature of the alkyne employed. This complex represents a convenient self-supported nickel(0) catalyst with no need for additional ligands and reducing agent.
Efficient Palladium(0) supported on reduced graphene oxide for selective oxidation of olefins using graphene oxide as a ‘solid weak acid’
Gao, Xi,Zhou, Jianhao,Peng, Xinhua
, p. 73 - 78 (2019/02/06)
Selective oxidation of olefin derivatives to ketones has made innovative development over palladium(0) supported on reduced graphene oxide. Compared to traditional Wacker oxidation, the novel method offers an economical and environment-friendly option by using graphene oxide (GO) as a ‘solid weak acid’ instead of classical homogeneous catalysts like H2SO4 and CF3COOH. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscopy images of Pd0/RGO showed that the nanoscaled Pd particles generated at the flake structure of reduced graphene oxide. Under optimized condition, up to 44 kinds of ketones with different structures can be prepared with excellent yields.
Synthesis, crystal structure, and supramolecular understanding of 1,3,5-tris(1-phenyl-1H-pyrazol-5-yl)benzenes
Martins, Marcos A. P.,Meyer, Alexandre R.,Salbego, Paulo R. S.,Dos Santos, Daniel M.,De Moraes, Guilherme A.,Bonacorso, Helio G.,Zanatta, Nilo,Frizzo, Clarissa P.,H?rner, Manfredo
, (2018/01/03)
Understanding the supramolecular environment of crystal structures is necessary to facilitate designing molecules with desirable properties. A series of 12 novel 1,3,5-tris(1-phenyl-1H-pyrazol-5-yl)benzenes was used to assess the existence of planar stacking columns in supramolecular structures of pyrazoles. This class of molecules with different substituents may assist in understanding how small structural changes affect the supramolecular environment. The obtained compounds did not present the formation of planar stacking interactions between benzenes in solid or liquid states. This supposition was indicated by single crystal diffraction, Density Functional Theory (DFT) and quantum theory of atoms in molecules (QTAIM) calculations, and concentration-dependent liquid-state1H nuclear magnetic resonance (NMR). NMR showed that chemical shifts of benzene and pyrazole hydrogens confirm that planar stacking interactions are not formed in solution. The crystalline structures presented different molecular conformations. The molecular structures of 5 and 9b are in a twisted conformation, while compound 7 showed a conformation analogous to a calyx form.
Transformation of Alkynes into Chiral Alcohols via TfOH-Catalyzed Hydration and Ru-Catalyzed Tandem Asymmetric Hydrogenation
Liu, Sensheng,Liu, Huan,Zhou, Haifeng,Liu, Qixing,Lv, Jinliang
supporting information, p. 1110 - 1113 (2018/02/23)
A novel full atom-economic process for the transformation of alkynes into chiral alcohols by TfOH-catalyzed hydration coupled with Ru-catalyzed tandem asymmetric hydrogenation in TFE under simple conditions has been developed. A range of chiral alcohols was obtained with broad functional group tolerance, good yields, and excellent stereoselectivities.
Organopromoted Selectivity-Switchable Synthesis of Polyketones
Liu, Jie,Hu, Kang-Fei,Qu, Jian-Ping,Kang, Yan-Biao
supporting information, p. 5593 - 5596 (2017/10/25)
In this work, an organopromoted metal-free pharmaceutical-oriented selectivity-switchable benzylic oxidation was developed, affording mono-, di-, and trioxygenation products, respectively, using oxygen as the oxidant under mild conditions. This process facilitates dioxygenation of 2,6-benzylic positions of heterocycles, which could be inhibited by heterocycle chelation to the metal cocatalysts. Enantiopure chiral ketones could also be prepared. The noninvolvement of transition metals and toxins avoids metal or hazardous residues, consequently ensuring a final-stage gram-scale synthesis of Lenperone.
Alternative tandem cyclisation pathways in the reaction between imines and enones
Girling, P. Ricardo,Batsanov, Andrei S.,Calow, Adam D.J.,Shen, Hong C.,Whiting, Andrew
, p. 1105 - 1113 (2016/07/06)
Dihydroisoquinoline reacts with Danishefsky's diene under Lewis acidic conditions or neat, to give low to moderate yields of the formal aza-Diels-Alder, [4+2]-cycloadduct. However, using methoxyvinyl methylketone with Lewis acid catalysis does not give the aza-Diels-Alder adduct, rather a formal [2+2+2]-cycloaddition occurs to provide access to a diacetyl dihydropyridine. Increased Lewis acid loading results in reduced dihydropyridine formation, and instead, a trimerisation reaction of the methoxyvinyl methyl ketone occurs, to give 1,3,5-triacetylbenzene from a different formal [2+2+2]-cycloaddition. The formal [4+2]-cycloaddition reaction of methoxyvinyl methylketone requires a cyclic imine in order to form the dihydropyridine because the reaction with acyclic imines produced a dihydropyridine from a formal [1+2+1+2]-cycloaddition. Evidence resulting from the isolation of reaction intermediates and in situ spectroscopic studies, shows that the reaction between 3,4-dihydroisoquinoline and methyl vinyl ketone, catalysed by oxy-philic Lewis acids, proceeds via a Mannich-Michael pathway and an imminium ion species. All reactions occur by one-pot cascade routes.
