Efficient C--C cross-coupling reactions by (isatin)-Schiff base functionalized magnetic nanoparticle-supported Cu(II) acetate as a magnetically recoverable catalyst

Abstract

Abstract:Copper catalysts were simply fabricated through surface modification of superparamagnetic iron nanoparticles with indoline-2,3-dione(isatin)-Schiff-base and interaction with Cu from low-cost commercially available starting materials. Catalysts were characterized using atomic absorption spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, UV/Vis spectroscopy, scanning electron microscopy, and transmission electron microscopy. These catalysts showed high efficiency for phosphine-free Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions with good diversity and generality. The catalysts could be easily recovered and reused several times without a significant loss in their catalytic activity and stability.

SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF MAGNETITE NANOPARTICLES (Fe3O4) AS POTENTIAL SOLID SUPPORT FOR HOMOGENEOUS CATALYSTS

“…The phase identification and crystalline structure of the as-prepared black MNPs were determined using X-ray powder diffraction. As shown in Figure 2, the diffraction peaks of the sample could be readily assigned to Fe 3 O 4 in accordance with the main characteristic peaks for magnetite reported in literature [11,14,15] and the standard values of Fe 3 O 4 (PDF card 75-449). The diffraction peaks at (220), (311), (400), (422), (511) and (440) of the crystalline Fe 3 O 4 nanoparticles reflect magnetite crystals with a cubic spinel structure [16].…”

“…There are three mass losses in the TGA curve. The first degradation peak is at about 30-200 ᵒC, which is around the boiling or evaporation point of absorbed water molecules [11]. The second peak is at the range of 250-400 ᵒC and the percentage of mass loss is about 9%, which…”

“…The formation of nanoparticles was confirmed by the black color precipitate acquired by the mixture [10]. A mixture of FeCl 2 .4H 2 O (1.0 g, 5.0 mmol) and FeCl 3 .6H 2 O (2.6 g, 9.6 mmol) was prepared in 100 mL distilled water under vigorous stirring and in the presence of N 2 gas [11]. Then, the solution was added dropwise to 10 mL ammonia solution (NH 4 OH 25 wt.%, excess).…”

Efficient multicomponent synthesis of 1,2,3-triazoles catalyzed by Cu(II) supported on PEI@Fe$_{3}$O$_{4}$ MNPs in a water/PEG$_{300}$ system

“…To address this issue, some copper-based catalytic systems have been reported. These systems include copper nanoparticles on activated carbon, 22,23 polymeric copper catalyst, 24−27 ionic liquid-supported Cu(I), 28−30 alumina-supported copper nanoparticles, 31 CuFe 2 O 4 , 32 silica-supported Cu(I), 33 nanoferrite-glutathione-copper, 34 nanosilica triazine dendrimer, 35 Cu(II) porphyrinbridged silsesquioxane PMO, 36 Cu@PMO NCs, 37 magnetic nanoparticle-supported Cu(II) acetate, 38 and silicaimmobilized NHC-Cu(I). 39 However, successful examples using this useful strategy are limited and some of them still use organic solvents, base, and reducing agents.…”

“…To address this issue, some copper-based catalytic systems have been reported. These systems include copper nanoparticles on activated carbon, 22 38 and silicaimmobilized NHC-Cu(I). 39 However, successful examples using this useful strategy are limited and some of them still use organic solvents, base, and reducing agents.…”