106380-62-5Relevant academic research and scientific papers
Visible Light-Mediated Direct Decarboxylative C-H Functionalization of Heteroarenes
Garza-Sanchez, R. Aleyda,Tlahuext-Aca, Adrian,Tavakoli, Ghazal,Glorius, Frank
, p. 4057 - 4061 (2017)
The direct visible light-mediated C-H alkylation of heteroarenes using aliphatic carboxylic acids is reported. This mild method proceeds at low catalyst loadings (0.5 mol %) and has a high functional group tolerance and a broad substrate scope. Notably, f
Development of a Quinolinium/Cobaloxime Dual Photocatalytic System for Oxidative C-C Cross-Couplings via H2Release
Li, Jianbin,Huang, Chia-Yu,Han, Jing-Tan,Li, Chao-Jun
, p. 14148 - 14158 (2021/11/27)
Designing molecular photocatalysts for potent photochemical reactivities ranks among the most challenging but rewarding endeavors in synthetic photochemistry. Herein, we document a quinoline-based organophotoredox catalyst, 2,4-bis(4-methoxyphenyl)quinoli
A dual biomimetic process for the selective aerobic oxidative coupling of primary amines using pyrogallol as a precatalyst. Isolation of the [5 + 2] cycloaddition redox intermediates
Deschamps, Patrick,Fleury, Maurice-Bernard,Hammad, Karim,Largeron, Martine
, p. 1894 - 1905 (2020/04/07)
A bioinspired organocatalytic cascade reaction mimicking both purpurogallin biosynthesis and copper amine oxidases (CuAOs) activity is described, at room temperature under ambient air, for the activation of the α-C-H bond of primary amines. The reaction sequence uses low-cost commercially available pyrogallol as a precatalyst which undergoes an in situ oxidative self-processing step, resulting in its conversion into natural purpurogallin, a [5 + 2] cycloaddition redox intermediate. This is further involved in the CuAOs-like transamination mechanism for producing, under single turnover, the active biomimetic organocatalyst which mediates the selective oxidative coupling of primary amines, including the non-activated substrates of CuAOs. Without any metal cocatalyst or additives, the protocol gives access to cross-coupled imines as well as 1,2-disubstituted benzimidazoles. The isolation of not easily accessible [5 + 2] cycloaddition redox intermediates provides direct and clear evidence for the proposed dual biomimetic process.
Green oxidant H2O2 as a hydrogen atom transfer reagent for visible light-mediated Minisci reaction
Zhao, Hong,Li, Zhenlong,Jin, Jian
supporting information, p. 12533 - 12537 (2019/08/21)
A visible light-mediated "green" protocol for metal-free oxidative coupling of heteroarenes and aliphatic C-H components has been achieved via a radical pathway. This cross-dehydrogenative coupling method features a broad scope of substrates. The green ox
Visible Light-Promoted Aliphatic C-H Arylation Using Selectfluor as a Hydrogen Atom Transfer Reagent
Zhao, Hong,Jin, Jian
supporting information, p. 6179 - 6184 (2019/09/06)
A mild, practical method for direct arylation of unactivated C(sp3)-H bonds with heteroarenes has been achieved via photochemistry. Selectfluor is used as a hydrogen atom transfer reagent under visible light irradiation. A diverse range of chem
A Bioinspired Organocatalytic Cascade for the Selective Oxidation of Amines under Air
Largeron, Martine,Fleury, Maurice-Bernard
supporting information, p. 6763 - 6767 (2017/06/05)
A bioinspired organocatalytic cascade reaction for the selective aerobic oxidative cross-coupling of primary amines to imines is described. This approach takes advantages of commercially available pyrogallol monomeric precursor to deliver low loadings of natural purpurogallin in situ, under air. This is further engaged in a catalytic process with the amine substrate affording, under single turnover, the active biomimetic quinonoid organocatalyst and the homocoupled imine intermediate, which is then converted into cross-coupled imine after dynamic transimination. This organocatalytic cascade inspired by both purpurogallin biosynthesis and copper amine oxidases allows the aerobic oxidation of non-activated primary amines that non-enzymatic organocatalysts were not able to accomplish alone.
Molecular Oxygen-Mediated Minisci-Type Radical Alkylation of Heteroarenes with Boronic Acids
Zhang, Lizhi,Liu, Zhong-Quan
supporting information, p. 6594 - 6597 (2017/12/26)
The carbon-carbon bond formation via autoxidation of organoboronic acid using 1 atm of O2 is achieved in a simple, clean, and green fashion. The approach allows a technically facile and environmentally benign access to structurally diverse heteroaromatics with medicinally privileged scaffolds. The strategy also displays its practicality and sustainability in the resynthesis of marketed drugs Crestor and pyrimethamine.
Catalytic Oxidative Coupling of Primary Amines under Air: A Flexible Route to Benzimidazole Derivatives
Nguyen, Khac Minh Huy,Largeron, Martine
, p. 1025 - 1032 (2016/03/01)
Benzimidazoles are of fundamental importance in chemistry and biology, and the development of efficient, environmentally benign methods for their preparation remains a key challenge for organic chemists. In a biomimetic approach inspired by copper amine oxidases, we disclose herein the scope and factors influencing the success of the cooperative action of CuBr2 as electron-transfer mediator and a topaquinone-like substrate-selective catalyst in the oxidative cyclocondensation of primary amines with o-aminoanilines. This one-pot atom-economic multistep process, which works under green conditions with ambient air as the terminal oxidant, low loadings of catalyst, and equimolar amounts of commercially available amine substrates, is particularly suitable for the preparation of 1,2-disubstituted benzimidazoles. Furthermore, it allows the functionalization of nonactivated primary aliphatic amines, which are known to be challenging substrates for non-enzymatic catalytic aerobic systems.
Direct alkylation of heteroarenes with unactivated bromoalkanes using photoredox gold catalysis
McCallum,Barriault
, p. 4754 - 4758 (2016/07/06)
Although visible light photoredox catalysis has emerged as a powerful tool for the construction of C-C bonds, common catalysts and/or their photoexcited states suffer from low redox potentials, limiting their applicability to alkyl radical generation from substrates with activated carbon-halogen bonds. Radicals derived from these activated compounds, being highly electrophilic or stabilized, do not undergo efficient addition to heteroarenes. Herein we describe the photocatalytic generation of nucleophilic alkyl radicals from unactivated bromoalkanes as part of a universal and efficient cross-coupling strategy for the direct alkylation of heteroarenes using a dimeric gold(i) photoredox catalyst, [Au2(bis(diphenylphosphino)methane)2]Cl2. The method proves to be efficient for alkylation of arenes under mild conditions in the absence of directing groups.
Metal-Free Oxidative Decarbonylative Coupling of Aliphatic Aldehydes with Azaarenes: Successful Minisci-Type Alkylation of Various Heterocycles
Tang, Ren-Jin,Kang, Lei,Yang, Luo
supporting information, p. 2055 - 2060 (2015/06/23)
A metal-free oxidative decarbonylative coupling of aliphatic aldehydes with various electron-deficient heterocycles has been developed. This reaction is supposed to be realized via a Minisci-type mechanism, based on the substrate scope, regioselectivity and radical trapping experiments. The ready availability of aliphatic aldehydes, metal-free conditions and broad substrate scope should make this method attractive for the late-stage alkylation of bioactive heterocycles.
