60344-99-2Relevant academic research and scientific papers
The effect of meta-substitution on the photochemical properties of benzoxazole derivatives
Ohshima, Asuka,Ikegami, Masashi,Shinohara, Yoshihiro,Momotake, Atsuya,Arai, Tatsuo
, p. 561 - 566 (2007)
The photochemistry of 2-(2-hydroxy-3-methoxyphenyl)benzoxazole (3-MHBO) and 2-(2-hydroxy-4-methoxyphenyl) benzoxazole (4-MHBO) have been investigated. The excited-state properties of 4-MHBO were similar to those for the parent compound 2-(2-hydroxyphenyl)
A Magnetic Heterogeneous Biocatalyst Composed of Immobilized Laccase and 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO) for Green One-Pot Cascade Synthesis of 2-Substituted Benzimidazole and Benzoxazole Derivatives under Mild Reaction Conditions
Mogharabi-Manzari, Mehdi,Kiani, Mahshid,Aryanejad, Sima,Imanparast, Somaye,Amini, Mohsen,Faramarzi, Mohammad Ali
, p. 3563 - 3571 (2018/09/22)
The design of reusable high-performance heterogeneous catalysts via the immobilization of chemical and biochemical species on magnetic nanoparticles increases the efficiency of catalytic systems by facilitating easy, fast, and clean separation processes. Laccase and 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl were separately immobilized on amine functionalized iron (II, III) oxide nanoparticles with covalent bonding using glutaraldehyde as a coupling reagent. The prepared catalyst was used to synthesize 12 benzoxazole and benzimidazole derivatives. The one-pot, two-step enzymatic aerobic oxidation reaction included the condensation of in situ-produced salicylaldehyde derivatives with aromatic amines, followed by an enzymatic dehydrogenation process. Optimal reaction conditions consisted of a citrate buffer (10 mM, pH 4.5) at 40 °C for an incubation time of 10 h and a heterogeneous catalyst containing immobilized laccase (80 mg, 100 U) and immobilized 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) (40 mg, 2 mol%). The catalyst retained more than 85% of its initial activity after 10 runs. In addition to the potential for reuse without significant losses in performance, eco-friendly attributes of this catalytic system include its high catalytic activity and the ease with which it can be recovered from the reaction mixture using an external magnet. (Figure presented.).
Highly efficient AgNO3-catalyzed approach to 2-(benzo[d]azol-2-yl)phenols from salicylaldehydes with 2-aminothiophenol, 2-aminophenol and benzene-1,2-diamine
He, Xinwei,Wu, Yuhao,Jin, Wenjing,Wang, Xiaoshun,Wu, Cong,Shang, Yongjia
, (2018/02/13)
A new, convenient and efficient AgNO3-catalyzed strategy for the preparation of 2-(benzo[d]azol-2-yl)phenol derivatives in good to excellent yields (63–98%) is described. The reaction proceeds via condensation/intramolecular nucleophilic addition/oxidation process between substituted salicylaldehydes and 2-aminothiophenol, 2-aminophenol or benzene-1,2-diamine under mild reaction conditions. Notably, this reaction utilizes cheap AgNO3 as a readily available and low-cost benign oxidant at low catalyst loadings with excellent functional group tolerance.
Rhodium(III)-Catalyzed ortho-Heteroarylation of Phenols through Internal Oxidative C-H Activation: Rapid Screening of Single-Molecular White-Light-Emitting Materials
Li, Bijin,Lan, Jingbo,Wu, Di,You, Jingsong
, p. 14008 - 14012 (2016/01/25)
Reported herein is the first example of a transition-metal-catalyzed internal oxidative C-H/C-H cross-coupling between two (hetero)arenes through a traceless oxidation directing strategy. Without the requirement of an external metal oxidant, a wide range of phenols, including phenol-containing natural products, can undergo the coupling with azoles to assemble a large library of highly functionalized 2-(2-hydroxyphenyl)azoles. The route provides an opportunity to rapidly screen white-light-emitting materials. As illustrative examples, two bis(triphenylamine)-bearing 2-(2-hydroxyphenyl)oxazoles, which are difficult to access otherwise, exhibit bright white-light emission, high quantum yield, and thermal stability. Also presented is the first example of the white-light emission, in a single excited-state intramolecular proton transfer system, of 2-(2-hydroxyphenyl)azoles, thus highlighting the charm of C-H activation in the discovery of new organic optoelectronic materials.
Synthesis of luminescent 2-(2′-hydroxyphenyl)benzoxazole (HBO) borate complexes
Massue, Julien,Frath, Denis,Ulrich, Gilles,Retailleau, Pascal,Ziessel, Raymond
, p. 230 - 233 (2012/02/16)
Complexation of boron trifluoride by a series of electron donor/acceptor substituted 2-(2′-hydroxy phenyl)benzoxazole (HBO) derivatives yields luminescent B(III) complexes with an emission wavelength ranging from 385 to 425 nm in dichloromethane or toluene. Appropriate chemical functionalization of these new dyes allows connection to different photoactive subunits (Boranil, BODIPY), endowing an efficient cascade energy transfer.
