67205-04-3Relevant academic research and scientific papers
A cooperative catalytic system of platinum/iridium alloyed nanoclusters and a dimeric catechol derivative: An efficient synthesis of quinazolines through a sequential aerobic oxidative process
Yuan, Hao,Yoo, Woo-Jin,Miyamura, Hiroyuki,Kobayashi, Shu
, p. 2899 - 2904 (2012)
A cooperative catalytic system of heterogeneous polymer-supported bi-metallic platinum/iridium (Pt/Ir) alloyed nanoclusters and 5,5′,6,6′-tetrahydroxy-3,3,3′,3′-tetramethyl-1, 1′-spiro-bisindane (TTSBI) enabled the facile preparation of quinazoline derivatives with low catalyst loadings and broad substrate scope under mild aerobic oxidative conditions. The ability to perform the reaction in gram-scale and under open-air conditions highlights the synthetic application of this cooperative catalytic system. Copyright
Method for catalyzing nitrogen heterocyclic ring aerobic dehydrogenation based on ionic liquid porous carbon material
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Paragraph 0057-0060, (2022/01/24)
The invention discloses a method for catalyzing nitrogen heterocycle aerobic dehydrogenation based on an ionic liquid porous carbon material, and is suitable for the field of organic synthesis. A heterogeneous catalysis system takes nitrogen heterocycle and derivatives thereof as substrates, a carbon material as a catalyst, water or ethanol as a solvent and air or oxygen spheres as an oxygen source, and a reaction is carried out at 0-80 DEG C under normal pressure, oxidative dehydrogenation of nitrogen heterocyclic compounds can be realized, and target products such as indole, quinoline, isoquinoline, quinazoline, quinoxaline, benzothiazole, Hanus ester and derivatives thereof and other medical intermediates can be synthesized. The non-metal catalyst is prepared by using the ionic liquid as the precursor, no activating agent or other additives are used in the reaction process, and the method has industrial application prospects.
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
supporting information, 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
Palladium(ii): N, N, O -pincer type complex-mediated dehydrogenative coupling of alcohols to quinazolines
Anandaraj, Pennamuthiriyan,Kumaradhas, Poomani,Ramesh, Rengan
, p. 16572 - 16580 (2021/10/01)
A new palladium(ii) N,N,O-pincer type complex-promoted one-pot cascade synthesis of quinazolines through the dehydrogenative coupling of easily available alcohols and 2-aminobenzylamine is reported. A distinct set of Pd(ii) complexes (1-2) was synthesized
Zinc Stabilized Azo-anion Radical in Dehydrogenative Synthesis of N-Heterocycles. An Exclusively Ligand Centered Redox Controlled Approach
Das, Siuli,Mondal, Rakesh,Chakraborty, Gargi,Guin, Amit Kumar,Das, Abhishek,Paul, Nanda D.
, p. 7498 - 7512 (2021/06/30)
Herein we report an exclusively ligand-centered redox controlled approach for the dehydrogenation of a variety of N-heterocycles using a Zn(II)-stabilized azo-anion radical complex as the catalyst. A simple, easy-to-prepare, and bench-stable Zn(II)-complex (1b) featuring the tridentate arylazo pincer, 2-((4-chlorophenyl)diazenyl)-1,10-phenanthroline, in the presence of zinc-dust, undergoes reduction to form the azo-anion radical species [1b]- which efficiently dehydrogenates various saturated N-heterocycles such as 1,2,3,4-tetrahydro-2-methylquinoline, 1,2,3,4-tetrahydro-isoquinoline, indoline, 2-phenyl-2,3-dihydro-1H-benzoimidazole, 2,3-dihydro-2-phenylquinazolin-4(1H)-one, and 1,2,3,4-tetrahydro-2-phenylquinazolines, among others, under air. The catalyst has further been found to be compatible with the cascade synthesis of these N-heterocycles via dehydrogenative coupling of alcohols with other suitable coupling partners under air. Mechanistic investigation reveals that the dehydrogenation reactions proceed via a one-electron hydrogen atom transfer (HAT) pathway where the zinc-stabilized azo-anion radical ligand abstracts the hydrogen atom from the organic substrate(s), and the whole catalytic cycle proceeds via the exclusive involvement of the ligand-centered redox events where the zinc acts only as the template.
Type I ‘Lighted Metal-free’ Photosensitizing Assemblies of Phenazine for Aerobic Oxidative Transformations
Kaur, Lovjot,Kaur, Harpreet,Kumar, Manoj,Bhalla, Vandana
supporting information, p. 4179 - 4186 (2021/11/23)
Highly photostable supramolecular photosensitizing ‘lighted metal-free’ assemblies of DPZ-Th have been developed which show strong absorption in the visible region and excellent electron transportation potential from donor to acceptor units. The as-prepar
Iron(II)-Catalyzed Aerobic Biomimetic Oxidation of N-Heterocycles
Manna, Srimanta,Kong, Wei-Jun,B?ckvall, Jan-E.
supporting information, p. 13725 - 13729 (2021/09/08)
Herein, an iron(II)-catalyzed biomimetic oxidation of N-heterocycles under aerobic conditions is described. The dehydrogenation process, involving several electron-transfer steps, is inspired by oxidations occurring in the respiratory chain. An environmentally friendly and inexpensive iron catalyst together with a hydroquinone/cobalt Schiff base hybrid catalyst as electron-transfer mediator were used for the substrate-selective dehydrogenation reaction of various N-heterocycles. The method shows a broad substrate scope and delivers important heterocycles in good-to-excellent yields.
Visible-light-mediated organoboron-catalysed metal-free dehydrogenation of N-heterocycles using molecular oxygen
Wei, Lanfeng,Wei, Yu,Xu, Liang,Zhang, Jinli
supporting information, p. 4446 - 4450 (2021/06/30)
The surge of photocatalytic transformation not only provides unprecedented synthetic methods, but also triggers the enthusiasm for more sustainable photocatalysts. On the other hand, oxygen is an ideal oxidant in terms of atom economy and environmental friendliness. However, the poor reactivity of oxygen at the ground state makes its utilization challenging. Herein, a visible-light-induced oxidative dehydrogenative process is disclosed, which uses an organoboron compound as the photocatalyst and molecular oxygen as the sole oxidant.Viathis approach, an array of N-heterocycles have been accessed under metal-free mild conditions, in good to excellent yields.
Method for preparing N - heterocyclic ring through visible light mediated dehydrogenation
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Paragraph 0080-0085, (2021/10/02)
The invention discloses a method for preparing N - heterocyclic rings through visible light mediated dehydrogenation, and the reaction can be carried out under the conditions of room temperature and visible light without heating. The novel tetra-coordination N-N - diaryl chelating borate compound serves as a photocatalyst, so that the use of a noble metal photocatalyst is avoided, precious metal residue in the reaction product can be reduced as much as possible, and the method is more suitable for synthesizing bioactive molecules.
Nickel-Catalyzed [4 + 2] Annulation of Nitriles and Benzylamines by C-H/N-H Activation
Sikari, Rina,Chakraborty, Gargi,Guin, Amit Kumar,Paul, Nanda D.
, p. 279 - 290 (2021/01/09)
Nickel-catalyzed [4 + 2] annulation of benzylamines and nitriles via C-H/N-H bond activation, providing straightforward atom-economic access to a wide variety of multisubstituted quinazolines, is reported. Mechanistic investigation revealed that the in situ formed amidines from the coupling of benzylamines and nitriles direct the nickel catalyst to activate the ortho-C-H bond of the phenyl ring of the benzylamine.
