In this work, an innovative nanocatalyst (Cu/SiO2-Pr-NH-Benz) was synthesized and applied to coupling and click reaction in an aqueous solution. This work reports an efficient and straightforward ...approach for synthesizing diverse propargylamine and 1,2,3-triazole derivatives in excellent yield and short-time reaction. Also, a novel method involving the Cu NPs supported on the SiO2 nanocatalyst as a heterogeneous novel catalyst for the “one-pot” three-component A3-coupling of aldehyde, amine, and alkynes and “one-pot” click reaction between alkyne, benzyl halide, and sodium azide in the water at room temperature was developed. Significant advantageous such as enhanced catalytic activity with efficient recycling for the one-pot synthesis of 1,4-disubstituted triazoles and propargyl amine derivatives and in green condition were observed. Also, after five successive reactions, the catalytic activity of recycled Cu/SiO2-Pr-NH-Benz remained high without significant loss in its intrinsic activity.
Copper nanoparticle; Multicomponent reaction; Click reaction; A3-coupling reaction, Silica nanocatalyst.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
chirality of sandwich type of organic molecules has been discovered. The key element of this chirality is characterized by three layers of structures that are arranged nearly in parallel fashion with ...one on top and one down from the center plane. Individual enantiomers of these molecules have been fully characterized by spectroscopies with their enantiomeric purity measured by chiral HPLC. The absolute configuration was unambiguously assigned by X-ray diffraction analysis. This is the first multilayer
chirality reported and is anticipated to lead to a new research area of asymmetric synthesis and catalysis and to have a broad impact on chemical, medicinal, and material sciences in future.
A new chiral aggregate-based tool for asymmetric synthesis has been developed by taking advantage of chiral aggregates of GAP (Group-Assisted Purification) reagents,
N
-phosphonyl imines. This tool ...was proven to be successful in the asymmetric GAP synthesis of functionalized 2,3-dihydrobenzofurans by reacting salicyl
N
-phosphonyl imines with dialkyl bromomalonates in various cosolvent systems. The chiral induction can be controlled by differentiating between two asymmetric directions simply by changing the ratios of cosolvents which are commonly adopted in AIE (aggregation-induced emission) systems. The formation of chiral aggregates was witnessed by a new analytical tool—aggregation-induced polarization (AIP). The present synthetic method will be broadly extended for general organic synthesis, particularly, for asymmetric synthesis and asymmetric catalysis in the future.
New multilayer 3D chiral molecules have been designed and synthesized asymmetrically through the strategy of center-to-multilayer folding chirality control and double Suzuki couplings. Individual ...diastereoisomers were readily obtained and separated
flash column chromatography. The key diastereoisomer was further converted into corresponding enantiomers. These enantiomers possess electron-deficient aromatic bridges layered with top and bottom aromatic scaffolds. X-ray structural analysis has unambiguously confirmed the configuration, and intermolecular packing results in regular planar patterns in solid crystals. The synthesis was achieved in a total of ten steps starting from commercially available starting materials.
Conjugated polymers and oligomers have great potentials in various fields, especially in materials and biological sciences because of their intriguing electronic and optoelectronic properties. In ...recent years, the through-space conjugation system has emerged as a new assembled pattern of multidimensional polymers. Here, a novel series of structurally condensed multicolumn/multilayer 3D polymers and oligomers have been designed and synthesized through one-pot Suzuki polycondensation (SPC). The intramolecularly stacked arrangement of polymers can be supported by either X-ray structural analysis or computational analysis. In all cases, polymers were obtained with modest to good yields, as determined by GPC and
H-NMR. MALDI-TOF analysis has proven the speculation of the step-growth process of this polymerization. The computational study of ab initio and DFT calculations based on trimer and pentamer models gives details of the structures and the electronic transition. Experimental results of optical and AIE research confirmed by calculation indicates that the present work would facilitate the research and applications in materials.
A new green magnetic nanocatalyst was introduced for one-pot fast synthesis of propargylamine and triazole derivatives. Chitosan bio-polymeric chains were functionalized with polyvinyl alcohol (PVA) ...and then templated with silver nanoparticles (AgNPs) and magnetic Fe3O4 to obtain the AgNPs/Fe3O4@chitosan/PVA composite. Spectral and analytical examinations were conducted using X-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and energy-dispersive X-ray spectroscopy for understanding the structural, morphological and physiochemical features of the obtained magnetic nanocomposite and the homogeneous distribution of AgNPs on the surface of nanocomposite with Fe3O4 nucleus. The AgNPs/Fe3O4@chitosan/PVA nanocatalyst was used in the synthesis of biologically active compounds such as propargylamine and triazole derivatives through multicomponent A3-coupling and click reactions. The catalyzed products were obtained in high yields under ambient conditions through a low-cost, facile, one-pot, and environmentally friendly protocol. The reusability of the heterogeneous magnetic catalyst was also confirmed up to six cycles without any significant loss in the catalytic activity, as well as easy separation of the catalyst.
In this work, we present a strategy for the preparation of functionalized 2,3-dihydrobenzofuran derivatives
via
the Cs
2
CO
3
-catalyzed domino annulation of enantiopure chiral salicyl
N
-phosphonyl ...imines with bromo malonates, which offers an avenue for the construction of 2,3-dihydrobenzofurans. Nineteen examples were synthesized in impressive chemical yields and diastereoselectivity. The products were purified simply by washing the crude mixtures with hexanes following group-assisted purification chemistry/technology to bypass traditional separation methods which often result in a loss of product. The absolute configuration was unambiguously assigned by X-ray structural analysis.
A new asymmetric method for the synthesis of highly functionalized 2,3-dihydrobenzofuranes in good to high yields and excellent diastereoselectivity
via
group-assisted purification (GAP) chemistry.
A new green magnetic nanocatalyst was introduced for one-pot fast synthesis of propargylamine and triazole derivatives. Chitosan bio-polymeric chains were functionalized with polyvinyl alcohol (PVA) ...and then templated with silver nanoparticles (AgNPs) and magnetic Fe
3
O
4
to obtain the AgNPs/Fe
3
O
4
@chitosan/PVA composite. Spectral and analytical examinations were conducted using X-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and energy-dispersive X-ray spectroscopy for understanding the structural, morphological and physiochemical features of the obtained magnetic nanocomposite and the homogeneous distribution of AgNPs on the surface of nanocomposite with Fe
3
O
4
nucleus. The AgNPs/Fe
3
O
4
@chitosan/PVA nanocatalyst was used in the synthesis of biologically active compounds such as propargylamine and triazole derivatives through multicomponent A
3
-coupling and click reactions. The catalyzed products were obtained in high yields under ambient conditions through a low-cost, facile, one-pot, and environmentally friendly protocol. The reusability of the heterogeneous magnetic catalyst was also confirmed up to six cycles without any significant loss in the catalytic activity, as well as easy separation of the catalyst.
A new green magnetic nanocatalyst was introduced for one-pot fast synthesis of propargylamine and triazole derivatives.
A new green magnetic nanocatalyst was introduced for one-pot fast synthesis of propargylamine and triazole derivatives. Chitosan bio-polymeric chains were functionalized with polyvinyl alcohol (PVA) ...and then templated with silver nanoparticles (AgNPs) and magnetic Fe 3 O 4 to obtain the AgNPs/Fe 3 O 4 @chitosan/PVA composite. Spectral and analytical examinations were conducted using X-ray diffraction, Fourier transform-infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and energy-dispersive X-ray spectroscopy for understanding the structural, morphological and physiochemical features of the obtained magnetic nanocomposite and the homogeneous distribution of AgNPs on the surface of nanocomposite with Fe 3 O 4 nucleus. The AgNPs/Fe 3 O 4 @chitosan/PVA nanocatalyst was used in the synthesis of biologically active compounds such as propargylamine and triazole derivatives through multicomponent A 3 -coupling and click reactions. The catalyzed products were obtained in high yields under ambient conditions through a low-cost, facile, one-pot, and environmentally friendly protocol. The reusability of the heterogeneous magnetic catalyst was also confirmed up to six cycles without any significant loss in the catalytic activity, as well as easy separation of the catalyst.
Abstract
The first enantioselective assembly of sandwich-shaped organo molecules has been achieved by conducting dual asymmetric Suzuki-Miyaura couplings and nine other reactions. This work also ...presents the first fully C-C anchored multi-layer 3D chirality with optically pure enantiomers. As confirmed by X-ray diffraction analysis that this chiral framework is featured by a unique C2-symmetry in which a nearly parallel fashion consisting of three layers: top, middle and bottom aromatic rings. Unlike the documented planar or axial chirality, the present chirality shows its top and bottom layers restrict each other from free rotation, i.e., this multi-layer 3D chirality would not exist if either top or bottom layer is removed. Nearly all multi-layered compounds showed strong luminescence of different colors under UV irradiation, and several randomly selected samples displayed aggregation-induced emission (AIE) properties. This work is believed to have broad impacts on chemical, medicinal and material sciences including optoelectronic materials in future.
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