4853-56-9Relevant articles and documents
Nelson et al.
, p. 399 (1968)
Synthesis, Characterization, and Photocatalytic Application of Type-II CdS/Bi2W2O9 Heterojunction Nanomaterials towards Aerobic Oxidation of Amines to Imines
Bhoi, Yagna Prakash,Mishra, Braja G.
, p. 2648 - 2658 (2018)
A series of new type-II CdS/Bi2W2O9 heterojunction nanomaterials is prepared by a two stage process. Initially, phase-pure Bi2W2O9, with orthorhombic crystalline structure, is prepared by a facile combustion-synthesis route. The combustion-synthesized Bi2W2O9 is subsequently modified by CdS nanoparticles using a hydrothermal route. The CdS/Bi2W2O9 heterojunctions are characterized using XRD, XPS, FTIR spectroscopy, UV/Vis DRS, PL, and FESEM and HRTEM studies. The occurrence of ultrafine CdS nanoparticles, with diameters of 8–15 nm, well-dispersed over BWO plates, is inferred from microscopic characterization studies. The two crystalline phases exhibit microscopic close contact across grain boundaries, facilitating the transfer of excitons. The heterojunction materials exhibit improved visible-light absorption, enhanced charge-carrier separation, and suitable band-alignment characteristics of a type-II heterojunction. The CdS/Bi2W2O9 heterojunctions are evaluated as visible-light-active photocatalysts for the aerobic oxidation of amines to imines. Structurally and functionally diverse amine molecules are oxidized to the corresponding imines, with excellent selectivity, in a short span of time.
Cyclometalated Half-Sandwich Iridium(III) Complexes: Synthesis, Structure, and Diverse Catalytic Activity in Imine Synthesis Using Air as the Oxidant
Li, Rong-Jian,Ling, Chun,Lv, Wen-Rui,Deng, Wei,Yao, Zi-Jian
, p. 5153 - 5162 (2021/05/04)
Four air-stable cyclometalated half-sandwich iridium complexes 1-4 with C,N-donor Schiff base ligands were prepared through C-H activation in moderate-to-good yields. These complexes have been well characterized, and their exact structure was elaborated on by single-crystal X-ray analysis. The iridium(III) complexes 1-4 showed good catalytic activity in the imine synthesis under open-flask conditions (air as the oxidant) from primary amine oxidative homocoupling, secondary amine dehydrogenation, and the cross-coupling reaction of amine and alcohol. Substituents bonded on the ligands of the iridium complexes displayed little effect on the catalytic efficiency. The stability and good catalytic efficiency of the iridium catalysts, mild reaction conditions, and substrate universality showed their potential application in industrial production.
Confined pyrolysis of a dye pollutant for two-dimensional F,N,S tri-doped nanocarbon as a high performance oxidative coupling reaction catalyst
Chen, Sian,Hu, Yajing,Li, Fang-Fang,Liu, Sijie,Peng, Ping,Wang, Haining,Yu, Ao,Yu, Bingzhe
, p. 7839 - 7847 (2020/11/30)
Nanocarbon materials as metal-free catalysts for the oxidative coupling of primary amines to imines suffer from high catalyst loading, low reaction rate and high oxygen demand. Doping heteroatoms in nanocarbons is realized as an effective strategy to improve the catalytic activity, however, the doping of fluorine has been rarely studied. Here we synthesized a F,N,S tri-doped hierarchical nanocarbon (FNSHC) by pyrolyzing a fluorine-containing azo-sulphonate dye (acid red-337, a pollutant in wastewater) confined in a layered double hydroxide (LDH). The LDH-confined synthetic method is beneficial to the formation of a two-dimensional porous structure with a large specific surface area (～1432 m2 g-1) and high fluorine content, enabling remarkable catalytic performance (98% yield in 4 h at 2 wt% catalyst loading under open-air conditions) and high recyclability, outcompeting current metal-free carbocatalysts. The conversion of environmental pollutants into heteroatom-doped carbon materials provides a new green strategy for the design and synthesis of functional carbon catalysts.
Uniform Cu/chitosan beads as a green and reusable catalyst for facile synthesis of iminesviaoxidative coupling reaction
Bunchuay, Thanthapatra,Chantiwas, Rattikan,Chutimasakul, Threeraphat,Intanin, Apichai,Na Nakhonpanom, Pakamon,Tantirungrotechai, Jonggol,Tirdtrakool, Warinda
, p. 21009 - 21018 (2020/06/22)
A nonprecious metal and biopolymer-based catalyst, Cu/chitosan beads, has been successfully prepared by using a software-controlled flow system. Uniform, spherical Cu/chitosan beads can be obtained with diameters in millimeter-scale and narrow size distribution (0.78 ± 0.04 mm). The size and morphology of the Cu/chitosan beads are reproducible due to high precision of the flow rate. In addition, the application of the Cu/chitosan beads as a green and reusable catalyst has been demonstrated using a convenient and efficient protocol for the direct synthesis of iminesviathe oxidative self- and cross-coupling of amines (24 examples) with moderate to excellent yields. Importantly, the beads are stable and could be reused more than ten times without loss of the catalytic performance. Furthermore, because of the bead morphology, the Cu/chitosan catalyst has greatly simplified recycling and workup procedures.
