7455-77-8Relevant academic research and scientific papers
A bagasse-supported magnetic manganese dioxide nanoparticle: applications in the selective aerobic oxidation of alcohols and one-pot tandem oxidative synthesis of quinazolinones
Farhid, Hassan,Hajishaabanha, Fatemeh,Rashidi Vahid, Adina,Shaabani, Ahmad,Shaabani, Shabnam
, (2022/01/24)
Magnetic manganese dioxide nanoparticles (MnO2-Fe3O4) were coated on sugarcane bagasse as a sugar industrial waste and bio-support (MnO2-Fe3O4@bagasse) via an in situ reduction strategy, in which potassium permanganate was used as the precursor of MnO2 and sugarcane bagasse as a bio-support and reducing agent of KMnO4. The synthesized bio-based catalyst was characterized by X-ray diffraction, thermogravimetric analysis, inductively coupled plasma optical emission spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, Brunauer–Emmett–Teller surface area analysis, and vibrating sample magnetometer analysis. The catalyst was successfully utilized in the selective aerobic oxidation of primary and secondary benzylic alcohols to their corresponding carbonyl compounds and one-pot tandem oxidative synthesis of 2-(substituted)quinazoline-4(3H)-ones from the o-aminobenzamide and aromatic alcohols in the absence of oxidizing reagent or initiator. Graphical abstract: [Figure not available: see fulltext.]
N^N^O hydrazone capped pincer type palladium complex catalysed construction of quinazolinones from alcohols
Anandaraj, Pennamuthiriyan,Kamatchi, Thangavel Sathiya,Ramesh, Rengan
, (2022/01/11)
New Pincer type Pd(II) complex [Pd(NNO)(PPh3)] (1) prompted synthesis of quinazolinones via dehydrogenative coupling of readily accessible alcohols, and o-aminobenzamide is described. A diverse range of quinazolinones has been synthesized efficiently with good to excellent yields employing low catalyst loading (0.5 mol%) under the aerobic condition without any additives/oxidants. A plausible mechanism for the construction of quinazolinones has been proposed via cyclic aminal intermediate. Large-scale synthesis attests to the productiveness of the current strategy.
Access to 2-Arylquinazolin-4(3H)-ones through Intramolecular Oxidative C(sp3)?H/N?H Cross-Coupling Mediated by I2/DMSO
Wen, Simiaomiao,Du, Yifan,Liu, Yiwen,Cui, Xiaofeng,Liu, Qixing,Zhou, Haifeng
, (2021/12/01)
A novel approach for the synthesis of 2-arylquinazolin-4(3H)-ones was developed. A series of title compounds were obtained with good functional group tolerance and good yields by I2/DMSO-mediated intramolecular oxidative cross-coupling of 2-(benzylamino)benzamides to form C=N double bonds. This method was applicable for gram-scale synthesis. A proposed reaction pathway based on some control experiments was also provided.
Aerobic primary and secondary amine oxidation cascade by a copper amine oxidase inspired catalyst
Thorve, Pradip Ramdas,Maji, Biplab
, p. 1116 - 1124 (2021/02/26)
Herein, we report a bioinspired catalytic system for the one-pot cascade oxidation of a native primary amine and anin situgenerated non-native secondary amine. The catalyst consists of ano-quinone cofactor phd (1,10-phenanthroline-5,6-dione) and a copper ion and operates under ambient air conditions. Quinazolin-4(3H)-ones, which are common pharmacophores present in numerous pharmaceuticals and bioactive compounds, were synthesized in high yields. A detailed kinetic and mechanistic study elucidates the role of the catalyst in the multi-step oxidative cascade reaction.
Electro-oxidative cyclization: Access to quinazolinones: Via K2S2O8without transition metal catalyst and base
Hou, Huiqing,Hu, Yongzhi,Ke, Fang,Sun, Weiming,Wu, Xianghua,Yu, Ling,Zhou, Sunying
, p. 31650 - 31655 (2021/11/30)
A K2S2O8-promoted oxidative tandem cyclization of primary alcohols with 2-aminobenzamides to synthesize quinazolinones was successfully achieved under undivided electrolytic conditions without a transition metal and base. The key feature of this protocol is the utilization of K2S2O8 as an inexpensive and easy-to-handle radical surrogate that can effectively promote the reaction via a simple procedure, leading to the formation of nitrogen heterocycles via direct oxidative cyclization at room temperature in a one-pot procedure under constant current. Owing to the use of continuous-flow electrochemical setups, this green, mild and practical electrosynthesis features high efficiency and excellent functional group tolerance and is easy to scale up.
Electrochemical synthesis of quinazolinone: via I2-catalyzed tandem oxidation in aqueous solution
Hou, Huiqing,Ma, Xinhua,Lin, Yingying,Lin, Jin,Sun, Weiming,Wang, Lei,Xu, Xiuzhi,Ke, Fang
, p. 17721 - 17726 (2021/05/29)
The development of protocols for synthesizing quinazolinones using biocompatible catalysts in aqueous medium will help to resolve the difficulties of using green and sustainable chemistry for their synthesis. Herein, using I2 in coordination with electrochemical synthesis induced a C-H oxidation reaction which is reported when using water as the environmentally friendly solvent to access a broad range of quinazolinones at room temperature. The reaction mechanism strongly showed that I2 cooperates electrochemically promoted the oxidation of alcohols, then effectively cyclizing amides to various quinazolinones.
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.
Visible light induced tandem reactions: An efficient one pot strategy for constructing quinazolinones using in-situ formed aldehydes under photocatalyst-free and room-temperature conditions
Xie, Zongbo,Lan, Jin,Zhu, Haibo,Lei, Gaoyi,Jiang, Guofang,Le, Zhanggao
supporting information, p. 1427 - 1431 (2020/11/02)
A facile tandem route has been developed for constructing quinazolinones from various aminobenzamides and in-situ generated aldehydes. Visible light was found to play a dual role: first oxidizes the alcohol to the aldehyde and then facilitates its cyclization with o-substituted aniline. Furthermore, alcohols are perfect alternatives to aldehydes because they are greener, more available, more economical, more stable, and less toxic than aldehydes. The first reaction step continuously provides material for the second step, which effectively reduces loss through volatilization, oxidation, and polymerization of the aldehyde, while avoiding its toxicity. A variety of quinazolinones can be prepared in the presence of visible light without any additional photocatalyst. The developed synthesis protocol proceeds with the merits of mild conditions, broad substrate scope, operational simplicity, and high atom efficiency, with an eco-energy source under metal-free, photocatalyst-free, and ambient conditions.
Palladium(II) N^O Chelating Complexes Catalyzed One-Pot Approach for Synthesis of Quinazolin-4(3 H)-ones via Acceptorless Dehydrogenative Coupling of Benzyl Alcohols and 2-Aminobenzamide
Balaji, Sundarraman,Balamurugan, Gunasekaran,Ramesh, Rengan,Semeril, David
, p. 725 - 734 (2021/04/06)
A convenient protocol for the one-pot synthesis of quinazolin-4(3H)-ones using palladium(II) complexes via dehydrogenative coupling of readily available benzyl alcohols and 2-aminobenzamide has been described. New structurally related Pd(II) N^O chelating complexes of general configuration [Pd(L)Cl(PPh3)] (where L = dimethylamino benzoylhydrazone ligands) have been designed and synthesized. The formation of the complexes has been recognized by analytical and spectral methods (FT-IR, NMR, HR-MS). The presence of a square-planar geometry around the palladium(II) ion was confirmed by single crystal X-ray diffraction study. A wide range of substituted quinazolinones have been successfully achieved from a diverse range of benzyl alcohols in good to excellent yields using 1.0 mol % of catalyst loading under aerobic conditions. Furthermore, control experiments reveal that the dehydrogenative coupling reaction involves initially the formation of an aldehyde intermediate and subsequent formation of a cyclic aminal intermediate.
Copper-Catalyzed One-Pot Synthesis of Quinazolinones from 2-Nitrobenzaldehydes with Aldehydes: Application toward the Synthesis of Natural Products
Pal, Shantanu,Sahoo, Subrata
, p. 18067 - 18080 (2021/12/06)
A novel, efficient, and atom-economical approach for the construction of quinazolinones from 2-nitrobenzaldehydes has been unveiled via copper-catalyzed nitrile formation, hydrolysis, and reduction in one pot for the first time. In this reaction, urea is used as a source of nitrogen for nitrile formation, hydrazine hydrate is used for both the reduction of the nitro group and the hydrolysis of nitrile, and atmospheric oxygen is used as the sole oxidant. The method portrays a wide substrate scope with good functional group tolerances. Moreover, this method was applied for the synthesis of schizocommunin, tryptanthrin, phaitanthrin-A, phaitanthrin-B, and 8H-quinazolino[4,3-b]quinazolin-8-one.
