- Laccase-Based Oxidative Catalytic Systems for the Aerobic Aromatization of Tetrahydroquinazolines and Related N-Heterocyclic Compounds under Mild Conditions
-
In this work, for the first time, laccase (metalloenzyme)/3,5-di-tert-butylcatechol (DTBC) as a new class of bioinspired quinone-based cooperative catalytic oxidation system and laccase/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) catalyst system were used for the aerobic oxidative synthesis of 2-substituted quinazolines through cascade reaction of structurally divers aldehydes with 2-aminobenzylamine. The products were obtained in good to high yields in phosphate buffer (0.1 m, 12.5 mL, pH = 4.5) and acetonitrile (4 vol.-%) mixture as solvent at 45 °C. Other N-heterocycles are also successfully oxidized to their aromatic counterparts.
- Saadati, Shaghayegh,Ghorashi, Nadya,Rostami, Amin,Kobarfard, Farzad
-
-
Read Online
- Copper (II) complex supported on the surface of magnetic nanoparticles modified with S-benzylisothiourea (Fe3O4@SiO2-SMTU-Cu): A new and efficient nanomagnetic catalyst for the synthesis of quinazolines and amides
-
A novel magnetically recoverable copper catalyst was successfully fabricated through the immobilization of Cu(NO3)2 on the surface of silica-coated magnetic Fe3O4 nanoparticles (Fe3O4@SiO2) functionalized with S-benzylisothiourea ligand. The Fe3O4@SiO2-SMTU-Cu nanocomposite was fully characterized by FT-IR spectroscopy, SEM, EDX, TGA, XRD, VSM, ASS and ICP-OES techniques. The Fe3O4@SiO2-SMTU-Cu nanocomposite exhibited high catalytic activity in the synthesis of biologically active quinazolines and amides. According to our research on the literature, this is the first report in the use of magnetic copper nanocatalyst for the synthesis of quinazolines. In this paper, we also presented tentative mechanisms for the synthesis of quinazolines and amides in the presence of catalytic amount of Fe3O4@SiO2-SMTU-Cu nanocomposite. This method gives notable advantages such as easy separation of the catalyst by external magnetic field; excellent yields, short reaction times, nontoxic metal catalyst, and simplicity of operation make this method a facile tool for the synthesis of quinazolines and amides.
- Fakri Mustafa, Yasser,Hussein Ali, Muneam,Jawad Shoja, Sarah,M. Kadhim, Mustafa,Riadi, Yassine,Sajjadi, Ahmad
-
supporting information
(2022/05/07)
-
- BTP-Rh@g-C3N4 as an efficient recyclable catalyst for dehydrogenation and borrowing hydrogen reactions
-
Highly active catalysts play an important role in modern catalysis. A novel and efficient ligand benzotriazole-pyrimidine (BTP) and the corresponding rhodium composite on C3N4 were successfully synthesized. The resulting rhodium composite was fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), thermogravimetric analysis (TGA), and x-ray photoelectron spectroscopy (XPS). The obtained composite exhibited good catalytic activity and good recovery performance in the synthesis of quinoxaline from 2-aminobenzyl alcohol and benzonitrile, and more than 20 quinoxalines were obtained in good yields. Additionally, it also showed that rhodium composite could achieved good catalytic performance in the synthesis of functionalized ketone through borrowing hydrogen strategy.
- Luo, Lan,Liu, Hongqiang,Zeng, Wei,Hu, Wenkang,Wang, Dawei
-
-
- Possible competitive modes of decarboxylation in the annulation reactions ofortho-substituted anilines and arylglyoxylates
-
Annulation reactions ofortho-substituted anilines and arylglyoxylates in the presence of K2S2O8at 80 °C under metal-free neutral conditions have been investigated, which extended a platform for the tandem synthesis of nitrogen heterocycles. While arylglyoxylic acids are known to undergo decarboxylation to form an acyl radical in the presence of K2S2O8and used in the Minisci acylation of electron-deficient (hetero)aromatics, their reactions with electron-richortho-substituted anilines to form nitrogen heterocycles have recently been studied. Depending upon the experimental conditions used in the reactions, the mechanism of the formation of heterocycles involving reactions of an acyl radical or aryl iminocarboxylic acids has been postulated. Given the subtle understanding of the mechanisms of annulation reactions of 2-substituted anilines and arylglyoxylates in the presence of K2S2O8, an extensive mechanistic investigation was undertaken. In the current study, the various mechanistic pathways including the generation of acyl, imidoyl, aminal, and N,O-hemiketal radicals have been postulated based on different possible decarboxylation modes. Some of the proposed intermediates are supported based on the available analytical data. The protocol uses a single, inexpensive reagent K2S2O8, which offers not only transition-metal-free conditions but also serves as the reagent for the key decarboxylation step. Taken together, this study complements the current development of the annulation reactions of 2-substituted anilines and arylglyoxylates in terms of synthesis and mechanistic understanding.
- Laha, Joydev K.,Panday, Surabhi,Tomar, Monika,Patel, Ketul V.
-
p. 845 - 853
(2021/02/09)
-
- Nickel-Catalyzed [4 + 2] Annulation of Nitriles and Benzylamines by C-H/N-H Activation
-
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.
- Sikari, Rina,Chakraborty, Gargi,Guin, Amit Kumar,Paul, Nanda D.
-
p. 279 - 290
(2021/01/09)
-
- Efficient synthesis of quinazolines by the iron-catalyzed acceptorless dehydrogenative coupling of (2-aminophenyl)methanols and benzamides
-
The acceptorless dehydrogenation coupling (ADC) of (2-aminophenyl)methanols with benzamides was achieved with catalytic FeCl2·4H2O in an efficient synthesis of quinazolines. This simple catalytic system is atom-economical, environmentally benign and suited to a variety of substrates.
- Zhang, Shi-Qi,Cui, Yao,Guo, Bin,Young, David J.,Xu, Ze,Li, Hong-Xi
-
-
- Zinc Stabilized Azo-anion Radical in Dehydrogenative Synthesis of N-Heterocycles. An Exclusively Ligand Centered Redox Controlled Approach
-
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.
- Das, Siuli,Mondal, Rakesh,Chakraborty, Gargi,Guin, Amit Kumar,Das, Abhishek,Paul, Nanda D.
-
p. 7498 - 7512
(2021/06/30)
-
- Mn(iii)-mediated cascade cyclization of 1-(azidomethyl)-2-isocyanoarenes with organoboronic acids: Construction of quinazoline derivatives
-
A novel and efficient Mn(iii)-mediated oxidative radical cascade reaction of 1-(azidomethyl)-2-isocyanoarenes with organoboronic acids is reported. The single electron oxidation of a commercially available organo boronic acid in the presence of a mild oxidant, Mn(OAc)3·2H2O, resulted in moderate yields of the corresponding quinazoline derivatives.
- Kumar, Gujjenahalli Ramalingaiah Yogesh,Begum, Noor Shahina
-
p. 9811 - 9817
(2021/06/15)
-
- A cobalt-catalyzed method for synthesizing quinoline and quinazoline compounds
-
The present invention discloses a cobalt-catalyzed synthesis of quinoline and quinazoline compounds, by a benzene compound with amino and hydroxyl groups or benzonitrile compounds as raw materials, in the presence of a catalyst and a base by a receptor-fr
- -
-
Paragraph 0021; 0065
(2022/01/10)
-
- Cooperative iridium complex-catalyzed synthesis of quinoxalines, benzimidazoles and quinazolines in water
-
Herein, an efficient methodology for the synthesis of a diverse class of N-heterocyclic moieties, such as quinoxalines, benzimidazoles and quinazolines, was developed in water using bio-renewable alcohols. The quinoxalines were successfully synthesized from a wide range of diamines and nitroamines with diols in air. Interestingly, benzimidazoles and quinazolines were synthesized with excellent isolated yields without using any external base. Finally, the preparative scale synthesis of various N-heterocycles and pharmaceutically active quinoxalines established the practicability of this protocol. For this iridium system, a metal-ligand cooperative mechanism was proposed based on kinetic and DFT studies.
- Chakrabarti, Kaushik,Maji, Milan,Kundu, Sabuj
-
supporting information
p. 1999 - 2004
(2019/04/27)
-
- Application of laccase/DDQ as a new bioinspired catalyst system for the aerobic oxidation of tetrahydroquinazolines and Hantzsch 1,4-dihydropyridines
-
Laccase/DDQ as a new bioinspired quinone-based cooperative catalytic system was used for the biomimetic aerobic oxidative synthesis of 2-substituted quinazolines and Hantzsch pyridines from the oxidative cyclocondensation of 2-aminobenzylamine and aldehyd
- Shariati, Mastaneh,Imanzadeh, Gholamhassan,Rostami, Amin,Ghoreishy, Nadya,Kheirjou, Somayyeh
-
p. 337 - 346
(2019/04/25)
-
- Synergistic catalysis on Fe-N: X sites and Fe nanoparticles for efficient synthesis of quinolines and quinazolinones via oxidative coupling of amines and aldehydes
-
In this paper, we developed a reusable heterogeneous non-precious iron nanocomposite comprising metallic Fe-Fe3C nanoparticles and Fe-Nx sites on N-doped porous carbon, which allows for highly efficient synthesis of quinolines and quinazolinones via oxidative coupling of amines and aldehydes using H2O2 as the oxidant in aqueous solution under mild conditions. A set of quinazolines and quinazolinones were synthesized in high yields with a broad substrate scope and good tolerance of functional groups. Characterization and control experiments disclose that a synergistic effect between the metallic Fe nanoparticles and built-in Fe-Nx sites is primarily responsible for the outstanding catalytic performance. Furthermore, the iron nanocomposite could be readily recovered for successive use without appreciable loss in catalytic activity and selectivity. This work provides an expedient and sustainable method to access pharmaceutically relevant N-heterocycles.
- Ma, Zhiming,Song, Tao,Yuan, Youzhu,Yang, Yong
-
p. 10283 - 10289
(2019/11/20)
-
- Method for preparing benzimidazole and quinazoline compounds by adopting supported nickel catalyst (by machine translation)
-
The invention discloses a method for synthesizing benzimidazole and quinazoline compounds by oxidative coupling and dehydrogenation of a nitrogen-doped hierarchical porous biomass-based carbon material supported catalyst and a preparation method. The method comprises the following steps: adding o-phenylenediamine compound, alcohol, supported catalyst, toluene and potassium tert-butoxide as a solvent, carrying out reaction under 50~150 °C conditions, carrying out reaction 4~24 hours, cooling to room temperature, filtering the reaction liquid, and obtaining a benzimidazole compound or quinazoline compound. The method adopts "one-pot method" preparation, the intermediate can be separated and purified, energy consumption can be reduced, and the efficiency. (by machine translation)
- -
-
Paragraph 0061-0063; 0064; 0066
(2019/07/16)
-
- Method for synthesizing quinazoline and quinazolinone compounds
-
The invention discloses a method for synthesizing quinazoline and quinazolinone compounds by oxidative coupling dehydrogenation with a nitrogen-doped hierarchical porous biomass basic carbon materialsupported catalyst. The method comprises the steps of adding 2-aminobenzylamine, 2-aminobenzamide, a formaldehyde compound R-CHO, the supported catalyst, a mixed solvent of water and tetrahydrofuran and hydrogen peroxide under a closed reaction condition, reacting at 60-140 DEG C for 6-24 hours, cooling to room temperature, filtering a reaction solution, and obtaining the quinazoline compound or the quinazolinone compound by silica gel column chromatography. The method adopts a low-cost metallic iron nanocatalyst through a 'one-pot' series reaction which is a green synthetic chemical strategy.Compared with a previous noble metal catalyst system, the reaction system is simple in operation, mild in condition and low in cost, and is favorable for large-scale production and industrial application.
- -
-
Paragraph 0042-0045; 0049
(2019/06/12)
-
- NNN pincer Ru(II)-catalyzed dehydrogenative coupling of 2-aminoarylmethanols with nitriles for the construction of quinazolines
-
An efficient NNN pincer Ru(II)-catalyzed preparation of quinazolines via acceptorless dehydrogenative strategy has been developed. Under the optimized conditions, a broad range of substituted o-aminobenzyl alcohols and (hetero)aryl or alkyl nitriles were well tolerated to afford various 2-substituted quinazolines in high yields. Subsequently, a set of control experiments have been performed to elucidate the reaction mechanism, which underwent alcohol oxidation, nitrile hydration, and cyclocondensation steps. The current protocol is featured with several advantages, such as environmental benignity, operational simplicity, broad substrate scope (compatible with aliphatic nitriles, up to 87% yield), and short reaction time (mostly in 2 h).
- Wan, Xiao-Min,Liu, Zi-Lin,Liu, Wan-Qing,Cao, Xiao-Niu,Zhu, Xinju,Zhao, Xue-Mei,Song, Bing,Hao, Xin-Qi,Liu, Guoji
-
p. 2697 - 2705
(2019/04/04)
-
- Dehydrogenative Synthesis of Quinolines, 2-Aminoquinolines, and Quinazolines Using Singlet Diradical Ni(II)-Catalysts
-
Simple, straightforward, and atom economic methods for the synthesis of quinolines, 2-aminoquinolines, and quinazolines via biomimetic dehydrogenative condensation/coupling reactions, catalyzed by well-defined inexpensive and easy to prepare singlet diradical Ni(II)-catalysts featuring two antiferromagnetically coupled singlet diradical diamine type ligands are described. Various polysubstituted quinolines, 2-aminoquinolines, and quinazolines were synthesized in moderate to good yields from different low-cost and readily accessible starting materials. Several control experiments were carried out to get insight into the reaction mechanism which shows that the nickel and the coordinated diamine ligands participate in a synergistic way during the dehydrogenation of alcohols.
- Chakraborty, Gargi,Sikari, Rina,Das, Siuli,Mondal, Rakesh,Sinha, Suman,Banerjee, Seemika,Paul, Nanda D.
-
p. 2626 - 2641
(2019/02/26)
-
- Accessing Polysubstituted Quinazolines via Nickel Catalyzed Acceptorless Dehydrogenative Coupling
-
Two environmentally benign methods for the synthesis of quinazolines via acceptorless dehydrogenative coupling of 2-aminobenzylamine with benzyl alcohol (Path A) and 2-aminobenzylalcohol with benzonitrile (Path B), catalyzed by cheap, earth abundant and easy to prepare nickel catalysts, containing tetraaza macrocyclic ligands (tetramethyltetraaza[14]annulene (MeTAA) or 6,15-dimethyl-8,17-diphenyltetraaza[14]annulene (MePhTAA)) are reported. A wide variety of substituted quinazolines were synthesized in moderate to high yields starting from cheap and easily available starting precursors. A few control reactions were performed to understand the mechanism and to establish the acceptorless dehydrogenative nature of the catalytic reactions.
- Parua, Seuli,Sikari, Rina,Sinha, Suman,Chakraborty, Gargi,Mondal, Rakesh,Paul, Nanda D.
-
p. 11154 - 11166
(2018/09/06)
-
- Molecular Iodine Catalysed Benzylic sp 3 C-H Bond Amination for the Synthesis of 2-Arylquinazolines from 2-Aminobenzaldehydes, 2-Aminobenzophenones and 2-Aminobenzyl Alcohols
-
Molecular iodine catalysed benzylic sp 3 C-H bond amination has been developed for the synthesis of quinazolines from 2-aminobenzaldehydes and 2-aminobenzophenones with benzylamines. The use of oxygen as a green oxidant combined with the transition-metal-, additive- and solvent-free conditions makes the methodology economical and greener. The lack of aqueous work up also enhances the efficiency of this protocol. A series of 2-arylquinazolines was synthesised in good to excellent yields by using the developed protocol. 2-Aminobenzyl alcohols could also be employed to prepare the corresponding quinazoline derivatives.
- Deshmukh, Dewal S.,Bhanage, Bhalchandra M.
-
supporting information
p. 979 - 985
(2018/04/23)
-
- Synthesis of 2-aryl quinazolines from (2-aminophenyl)methanol and oxime ether catalyzed by copper ferrite nanoparticles
-
Magnetically separable copper ferrite nps as a catalytic system, under solvent free reaction condition for synthesis of 2-arylquinazolines has been reported. (2-aminoaryl)methanols and various types of oxime ethers were efficiently converted into desired products in moderate to good yields. This protocol offers a greener and atom efficient process, using recyclable heterogeneous catalytic system.
- Sarode, Sachin A.,Jadhav, Vilas G.,Nagarkar, Jayashree M.
-
supporting information
p. 779 - 784
(2017/03/31)
-
- A facile and versatile protocol for the one-pot PhI(OAc)2 mediated divergent synthesis of quinazolines from 2-aminobenzylamine
-
In this present work iodobenzenediacetate (PIDA) has been found to be the key reagent in absence or presence of catalytic amount of molecular iodine (I2)/zinc chloride (ZnCl2) to construct quinazoline scaffold from 2-aminobenzylamine and a variety of easily available aldehydes, aryl and aliphatic amines, aliphatic and aryl alcohols and nitriles. This protocol provides mild and robust conditions along with great versatility to synthesize 2-substituted quinazolines from diverse starting materials in good to excellent yields. The developed protocol is also well applicable to reactants containing ease to oxidation prone functional groups.
- Saha, Moumita,Mukherjee, Prasun,Das, Asish R.
-
supporting information
p. 2044 - 2049
(2017/05/04)
-
- Dehydrogenation of Nitrogen Heterocycles Using Graphene Oxide as a Versatile Metal-Free Catalyst under Air
-
Graphene oxide (GO) has been developed as an inexpensive, environmental friendly, metal-free carbocatalyst for the dehydrogenation of nitrogen heterocycles. Valuable compounds, such as quinoline, 3,4-dihydroisoquinoline, quinazoline, and indole derivatives, have been successfully used as substrates. The investigation of various oxygen-containing molecules with different conjugated systems indicated that both the oxygen-containing groups and large π-conjugated system in GO sheets are essential for this reaction. (Figure presented.).
- Zhang, Jingyu,Chen, Shiya,Chen, Fangfang,Xu, Wensheng,Deng, Guo-Jun,Gong, Hang
-
supporting information
p. 2358 - 2363
(2017/07/22)
-
- Iron-catalyzed cascade reaction of 2-aminobenzyl alcohols with benzylamines: Synthesis of quinazolines by trapping of ammonia
-
A novel approach to construct 2-aryl/heteroaryl quinazolines was developed through an iron-catalyzed cascade reaction of 2-aminobenzyl alcohols with benzylamines under aerobic oxidative conditions. The reaction proceeds via the formation of N-benzylideneb
- Gopalaiah, Kovuru,Saini, Anupama,Devi, Alka
-
p. 5781 - 5789
(2017/07/22)
-
- Synthesis of 2-substituted quinazolines by CsOH-mediated direct aerobic oxidative cyclocondensation of 2-aminoarylmethanols with nitriles in air
-
By using air as the superior oxidant, a highly atom-efficient synthesis of 2-substituted quinazolines is developed by a CsOH-mediated direct aerobic oxidative reaction of the readily available and stable 2-aminoarylmethanols and nitriles. Effectively working as the promoter in the alcohol oxidation, nitrile hydration, and cyclocondensation steps, CsOH is the best base for the reaction. A similar method can also be extended to the synthesis of substituted quinolines starting from methyl ketones instead of nitriles.
- Yao, Song,Zhou, Kaijing,Wang, Jiabing,Cao, Hongen,Yu, Lei,Wu, Jianzhang,Qiu, Peihong,Xu, Qing
-
supporting information
p. 2945 - 2951
(2017/07/24)
-
- Synthesis of quinazolines from 2-aminobenzylamines with benzylamines and N-substituted benzylamines under transition metal-free conditions
-
This work reports the synthesis of quinazolines from 2-aminobenzylamines with N-substituted benzylamines in the presence of molecular iodine. The developed methodology works smoothly under transition-metal free, additive free and solvent free conditions. The use of O2 as a green oxidant makes it a greatly economical, green and sustainable protocol. Moreover, no aqueous work up is required thereby enhancing the efficiency. A series of quinazoline derivatives were synthesized successfully in good to excellent yields.
- Tiwari, Abhishek R.,Bhanage, Bhalchandra M.
-
supporting information
p. 10567 - 10571
(2016/11/30)
-
- Magnesium iodide-catalyzed synthesis of 2-substituted quinazolines using molecular oxygen and visible light
-
A novel and efficient approach for the synthesis of quinazolines by aerobic photooxidation with an iodine reagent at room temperature is reported. This method uses harmless visible light from compact fluorescent lamps and molecular oxygen as the sole oxid
- Yamaguchi,Sakairi,Yamaguchi,Tada,Itoh
-
p. 56892 - 56895
(2016/07/07)
-
- Synthesis method for 2-substituted quinazoline heterocyclic compound
-
The invention discloses a synthesis method for a 2-substituted quinazoline heterocyclic compound. According to the efficient synthesis method, 2-aminobenzylalcohol and nitrile are subjected to an oxidation-cyclization reaction in air under the alkaline condition to prepare the 2-substituted quinazoline heterocyclic compound. By means of the method, no transition metal catalyst or ligand is needed, and the reaction is directly carried out through heating under the alkaline condition to obtain the 2-substituted quinazoline heterocyclic compound. The reaction condition is simple, operation is easy, air serves as an economical, safe and environment-friendly catalyst, a by-product is water, and atom efficiency is high. The requirement of the method for the reaction condition is low, and the method has certain research and industrial application prospects.
- -
-
Paragraph 0041; 0042; 0043; 0044
(2016/12/22)
-
- Copper-Catalyzed Multicomponent Domino Reaction of 2-Bromoaldehydes, Benzylamines, and Sodium Azide for the Assembly of Quinazoline Derivatives
-
An efficient three-component domino reaction of 2-bromoaldehydes, benzylamines, and sodium azide has been developed for the synthesis of quinazoline derivatives. This domino process involves copper-catalyzed SNAr, oxidation/cyclization, and denitrogenation sequences. The mild catalytic system enabled the effective construction of three C-N bonds in one operation.
- Xu, Cheng,Jia, Feng-Cheng,Zhou, Zhi-Wen,Zheng, Si-Jie,Li, Han,Wu, An-Xin
-
p. 3000 - 3006
(2016/04/26)
-
- A convenient palladium-catalyzed carbonylative synthesis of quinazolines from 2-aminobenzylamine and aryl bromides
-
A novel and practical strategy towards quinazoline scaffolds synthesis has been achieved. Through palladium-catalyzed carbonylative coupling of 2-aminobenzylamine with aryl bromides, the desired quinazolines were produced in moderate to good yields for the first time. The reactions followed an aminocarbonylation-condensation-oxidation sequence in a one-pot one-step manner. Preliminary investigation showed DMSO serves both as solvent and oxidant in this procedure.
- Chen, Jianbin,Natte, Kishore,Neumann, Helfried,Wu, Xiao-Feng
-
p. 56502 - 56505
(2015/02/02)
-
- Bioinspired aerobic oxidation of secondary amines and nitrogen heterocycles with a bifunctional quinone catalyst
-
Copper amine oxidases are a family of enzymes with quinone cofactors that oxidize primary amines to aldehydes. The native mechanism proceeds via an iminoquinone intermediate that promotes high selectivity for reactions with primary amines, thereby constraining the scope of potential biomimetic synthetic applications. Here we report a novel bioinspired quinone catalyst system consisting of 1,10-phenanthroline-5,6-dione/ZnI2 that bypasses these constraints via an abiological pathway involving a hemiaminal intermediate. Efficient aerobic dehydrogenation of non-native secondary amine substrates, including pharmaceutically relevant nitrogen heterocycles, is demonstrated. The ZnI2 cocatalyst activates the quinone toward amine oxidation and provides a source of iodide, which plays an important redox-mediator role to promote aerobic catalytic turnover. These findings provide a valuable foundation for broader development of aerobic oxidation reactions employing quinone-based catalysts.
- Wendlandt, Alison E.,Stahl, Shannon S.
-
supporting information
p. 506 - 512
(2014/01/23)
-
- Synthesis of 2-substituted quinazolines via iridium catalysis
-
An iridium-catalyzed hydrogen transfer reaction was successfully applied in the synthesis of 2-substituted quinazolines in moderate yields starting from aldehydes or alcohols with 2-aminobenzylamines.
- Fang, Jie,Zhou, Jianguang,Fang, Zhijie
-
p. 334 - 336
(2013/03/28)
-
- Mild and efficient ligand-free copper-catalyzed condensation for the synthesis of quinazolines
-
Condensation of o-iodobenzaldehydes 1a_c with amidine hydrochlorides 2a_p under ligand-free copper-catalyzed Ullmann N-arylation conditions afforded the corresponding quinazolines 3a-r in good to excellent yields.
- Truong, Vouy Linh,Morrow, Michelle
-
scheme or table
p. 758 - 760
(2010/04/05)
-