91-63-4Relevant academic research and scientific papers
Iridium catalyzed reversible dehydrogenation - Hydrogenation of quinoline derivatives under mild conditions
Manas, Michael G.,Sharninghausen, Liam S.,Lin, Elisa,Crabtree, Robert H.
, p. 184 - 189 (2015)
Abstract The potential of a hydrogen-based energy economy is limited by the fact that hydrogen gas is difficult to store and transport. Storing hydrogen in the form of liquid organic hydrogen-carriers (LOHCs) is a highly attractive alternative to current options but it requires the development of catalytic means of reversibly hydrogenating and dehydrogenating these carriers under mild conditions and ideally using a single catalyst for both processes. We report the optimization of two families of previously reported hydrogenation catalysts for the reverse reaction, dehydrogenation of N-heterocyclic substrates. These complexes are capable of catalyzing both dehydrogenation and hydrogenation reactions in alternation, giving high yields in both directions. Importantly, our complexes do not require high temperatures, high pressures of H2 or strong base for the hydrogenation step.
Redox-active cyclopentadienyl Ni complexes with quinoid N-heterocyclic carbene ligands for the electrocatalytic hydrogen release from chemical fuels
Luca, Oana R.,Huang, Daria L.,Takase, Michael K.,Crabtree, Robert H.
, p. 3402 - 3405 (2013)
We now report the electrocatalytic dehydrogenation of tetrahydroquinaldine by an electron-rich CpNi N-heterocyclic carbene (NHC) with quinoid ligand motifs and explore the effects of quinone additives on CpNi compounds without quinoid NHC ligands. Our CpNi(NHC) catalyst exhibits dehydrogenative electrocatalytic activity and demonstrates that a molecular catalyst precursor can be viable in the electrode-driven (H+ + e-) release step of "virtual hydrogen storage".
Oxygen-implanted MoS2 nanosheets promoting quinoline synthesis from nitroarenes and aliphatic alcohols via an integrated oxidation transfer hydrogenation-cyclization mechanism
Gao, Zhuyan,Huang, Zhipeng,Lu, Jianmin,Mu, Junju,Ren, Puning,Su, Kaiyi,Wang, Feng,Zhang, Chaofeng,Zhang, Shichao
, p. 1704 - 1713 (2022/03/08)
We herein report that MoS2 with oxygen-implanting modification (O-MoS2) can work as a multifunctional catalyst to achieve the one-pot quinoline synthesis from basic nitroarenes and aliphatic alcohols. Different from common knowledge that the application of MoS2-based catalysts and above quinoline synthesis need anaerobic conditions, we conduct the heterogeneous catalysis under an unusual air atmosphere. Catalyst characterization and experimental results indicate that the MoOx clusters implanted in the MoS2 skeleton, not the coordinatively unsaturated Mo sites (CUS Mo), dominate the generation of quinolines. By overturning the catalysis perception that O2 adsorption on MoSx can deactivate the MoS2-based catalysts using an efficient method for in situ healing of the MoOx structure in O-MoS2 and protecting the O-MoS2 catalyst by inhibiting unwanted MoOx elimination with extra H*, we innovatively introduce O2 into the quinoline synthesis. The robust O-MoS2 can be consecutively used ten times without regeneration and it offers 69-75% yields of 2-methylquinoline from nitrobenzene and ethanol. Furthermore, different from the traditional transfer hydrogenation-condensation mechanism, an integrated oxidation-transfer hydrogenation-cyclization mechanism is proposed over the O-MoS2 catalyst.
Photocatalytic Synthesis of Quinolines via Povarov Reaction under Oxidant-Free Conditions
Su, Long-Long,Zheng, Yi-Wen,Wang, Wen-Guang,Chen, Bin,Wei, Xiang-Zhu,Wu, Li-Zhu,Tung, Chen-Ho
supporting information, p. 1180 - 1185 (2022/02/14)
We describe here an approach for synthesizing quinolines either from N-alkyl anilines or from anilines and aldehydes. A dual-catalyst system consisting of a photocatalyst and a proton reduction cocatalyst is employed. Without the use of any sacrificial ox
A biomass-derived N-doped porous carbon catalyst for the aerobic dehydrogenation of nitrogen heterocycles
Cui, Fu-Jun,Guo, Fu-Hu,Liu, Jing-Jiang,Liu, Xiao-Yu,Quan, Zheng-Jun,Ullah, Arif,Wang, Xi-Cun,Zhu, Ji-Hua
, p. 1791 - 1799 (2022/01/31)
N-doped porous carbon (NC) was synthesized from sugar cane bagasse, which is a sustainable and widely available biomass waste. The preferred NC sample had a well-developed porous structure, a graphene-like surface morphology and different N species. More
Rhodium-Catalyzed C-H Annulation of Free Anilines with Vinylene Carbonate as a Bifunctional Synthon
Nan, Jiang,Yin, Jiacheng,Gong, Xue,Hu, Yan,Ma, Yangmin
supporting information, p. 8910 - 8915 (2021/11/24)
Chemical transformation with vinylene carbonate as an emerging synthetic unit has recently attracted considerable attention. This report is a novel conversion pattern with vinylene carbonate, in which such a vibrant reagent unprecedentedly acts as a difunctional coupling partner to complete the C-H annulation of free anilines. From commercially available substrates, this protocol leads to the rapid construction of synthetically versatile 2-methylquinoline derivatives (43 examples) with excellent functionality tolerance.
Effect of Terminal Alkylation of Aryl and Heteroaryl Hydrazines in the Fischer Indole Synthesis
Schmidt, Michael A.
, (2021/04/12)
The effect of alkylation on the terminal position of aryl and heteroaryl hydrazines in the Fischer indole synthesis was examined. Compared to their unalkylated counterparts, reactions using alkylated hydrazines provided indole products with higher yields and faster rates. The reactions can be conducted at lower temperatures and are compatible with acid-sensitive functionality. The terminally alkylated hydrazines were readily prepared by a new two-step sequence and held as stable hydrazinium salts. The mild formation of the salts along with the favorable Fischer indole reaction conditions highlights the potential of this approach in later-stage synthetic use.
Mild and efficient copper-catalyzed oxidative cyclization of oximes with 2-aminobenzyl alcohols at room temperature: synthesis of polysubstituted quinolines
Liu, Yan-Yun,Wei, Yang,Huang, Zhi-Hui,Liu, Yilin
supporting information, p. 659 - 666 (2021/02/06)
A simple and efficient ligand-free Cu-catalyzed protocol for the synthesis of polysubstituted quinolinesviaoxidative cyclization of oxime acetates with 2-aminobenzyl alcohols at room temperature has been developed. The presented approach provides a new synthetic pathway leading to polysubstituted quinolines with good functional group tolerance under mild conditions. Moreover, this transformation can be applied for the preparation of quinolines on a gram scale. Oxime acetates serve as the internal oxidants in the reactions, thus making this method very attractive.
Porous FeO(OH) Dispersed on Mg-Al Hydrotalcite Surface for One-Pot Synthesis of Quinoline Derivatives
Motokura, Ken,Ozawa, Nao,Sato, Risako,Manaka, Yuichi,Chun, Wang-Jae
, p. 2915 - 2921 (2021/05/27)
The use of ubiquities elements such as iron instead of expensive precious metals as catalysts is one goal toward realizing environmentally benign synthetic chemistry. Here, we report that porous FeO(OH) dispersed on Mg?Al hydrotalcite acts as a bifunctional heterogeneous catalyst in the one-pot synthesis of 2-substituted quinoline derivatives through dehydrogenative oxidation-cyclization reactions. The catalyst was prepared by a simple grafting method using FeCl3 and Mg?Al hydrotalcite. The prepared porous FeO(OH) possesses a higher surface area than those previously reported for α-FeO(OH) particles. The one-pot quinoline synthesis proceeded effectively under non-noble-metal catalysis in air without requiring additional homogeneous bases or solvents.
Method for realizing oxidative dehydrogenation of nitrogen-containing heterocyclic ring by using biomass-based carbon material
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Paragraph 0010-0011; 0018-0019, (2021/06/26)
The invention provides a method for realizing oxidative dehydrogenation of a nitrogen-containing heterocyclic ring by using a biomass-based carbon material, and belongs to the field of organic synthesis. According to the method, the raw materials of the biomass-based carbon material comprise wheat, sorghum, rice, corn straw, wheat straw, peanut shells, sesame shells, bean shells and the like, and are crushed and then ground into powder, the powder is fully mixed with an inorganic alkali, and calcination is performed in an inert gas atmosphere to prepare the biomass-based carbon material; and by using air as an oxygen source, at a temperature of 50-120 DEG C, oxidative dehydrogenation of nitrogen-containing heterocyclic compounds to synthesize quinoline compounds, isoquinoline compounds, acridine compounds, quinazoline compounds, indole compounds, imine compounds, and even quinoline compounds with pharmaceutical activity can be achieved. According to the present invention, easily available wheat flour is adopted as a raw material to prepare a non-metal catalyst, the alkali is not added during the reaction process, and a remarkable industrial application prospect is achieved.
