scholarly journals One-Step Direct Amination of Nanodiamond Surface and Facile Separation by Viscosity Gradient Centrifugation

2019 ◽  
Author(s):  
Nianshun Yang ◽  
Jean Felix Mukerabigwi ◽  
Xueying Huang ◽  
Yuyang Sun ◽  
Juanxiao Cai ◽  
...  
Keyword(s):  
Gradient Centrifugation ◽  
Mechanochemical Reaction ◽  
Distribution Analysis ◽  
One Pot ◽  
Direct Amination ◽  
Wide Range ◽  
One Step ◽  
Ft Ir ◽  
Synthesis Procedure ◽  
Mechanochemical Reactions

Abstract: The introduction of terminal amine functional group on nanodiamond (ND) surface has been proposed as the key strategy to enable further synthesis of various ND derivatives for a wide range of application including sensors and biomedicine. Nevertheless, it is still challenging to develop a successful synthesis procedure to achieve monodispersed ND-NH2 mostly due to the undesirable high agglomeration effect of ND particles and complex synthetic steps which dramatically limit their practical use. In this work, we demonstrate a facile approach to obtain the direct amination of the ND surface, through a one pot mechanochemical reaction using ball milling in the presence of NH4Cl. To obtain monodispersed ND-NH2, a straightforward process by virtue of viscosity gradient centrifugation is adopted using aqueous polyvinylpyrrolidone (PVP) and glycerol. The results show a successful synthesis of ND-NH2 as evidenced by FT-IR and ζ–potential analysis. Moreover, the aminated ND particles morphology and size distribution analysis by TEM and DLS, respectively, show that using viscosity gradient built from aqueous PVP can achieve a better separation of NDs by size. Therefore, the findings suggested that the application of mechanochemical reactions and viscosity gradient centrifugation can be used to achieve homogeneous and monodispersed functionalized NDs for further specific technical applications.

scholarly journals One Pot Synthesis of CoTiO3-TiO2 Composite Nanofibers and its Application in Dye Degradation

2021 ◽  
pp. 1597-1607
Author(s):  
M. Shamshi Hassan
Keyword(s):  
Visible Light ◽  
Composite Nanofibers ◽  
Dye Degradation ◽  
Band Gap Energy ◽  
One Pot ◽  
Light Region ◽  
Composite Photocatalysts ◽  
One Step ◽  
Ft Ir ◽  
The One

CoTiO3-TiO2 composite nanofibrous photocatalysts were synthesized by means of the one-step electrospinning method. The samples were characterized by a range of different methods (XRD, SEM, EPMA, FT-IR, UV-DRS, and TEM). Photocatalytic activity was performed for the degradation of rhodamine 6G under visible light. The results showed that CoTiO3-TiO2 composite photocatalysts were successfully synthesized. The average sizes of the diameters of the composite nanofibers were found to be 300 to 400 nm. The UV–Vis diffuse reflectance spectra of the CoTiO3-TiO2 composite showed an absorption wavelength, in the visible light region, having a band gap energy value of 2.21 eV. The CoTiO3-TiO2 composite showed higher photocatalytic efficiency than that of pristine TiO2; which can be attributed to the heterojunctional interaction between CoTiO3 and TiO2.

scholarly journals Efficient and mild synthesis of pyrano-pyrimidines catalyzed by decorated multi-walled carbon nanotubes bearing cobalt, nickel and copper metals in water

2021 ◽  
Author(s):  
Nasrin Saberi Harouni ◽  
Hossein Naeimi
Keyword(s):  
Reaction Times ◽  
Single Step ◽  
High Yield ◽  
One Pot ◽  
H Nmr ◽  
Multi Walled Carbon Nanotubes ◽  
Nmr Techniques ◽  
One Step ◽  
Ft Ir ◽  
Walled Carbon Nanotubes

Abstract Multicomponent reactions are reactions in which three or more are agreeable of raw interests, composed in a one-step chemical process and the product is formed they give. Since multivariate reactions are monovalent reactions and Single-step conversions to ideal synthesis are very close. In this research, one pot three components reaction was carried out between 1, 3-dimethylbarbituric acid, malononitrile and different aldehydes in the attendance of Cu/Co/Ni/MWCNTs as a recyclable catalyst. This catalyst indicated high catalytic actuality with good proficiency and reusable under mild reservation. This reaction is performed fine at ambient temperature. This method proposed numerous materials such as being environmentally amicable for short reaction times and creating high yield products. The catalysts were collected and specified with diversity spectroscopic, such as techniques, such as FT-IR, X-ray fracture, and scanning electron microscopy. After finalization of the reaction, the vintage was obsolete, purified and identified by the melting points, infrared spectroscopy (FT-IR) and the magnetic resonance of the hydrogen nucleus (1H NMR) techniques.

A One-Pot Hydrothermal Synthesis of Eu/BiVO4 Enhanced Visible-Light-Driven Photocatalyst for Degradation of Tetracycline

2020 ◽  
Vol 20 (5) ◽  
pp. 3053-3059 ◽  
Author(s):  
Zhenzhao Pei ◽  
Heng Jia ◽  
Yulong Zhang ◽  
Pei Wang ◽  
Yabao Liu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Active Species ◽  
Photocatalytic Process ◽  
One Pot ◽  
Photodegradation Efficiency ◽  
Activity Test ◽  
Visible Light Driven ◽  
One Step ◽  
Ft Ir

Eu/BiVO4 photocatalyst was synthesized by a facile one-step hydrothermal method. The structures and morphologies of Eu/BiVO4 photocatalysts were investigated by XRD, SEM and FT-IR and their photocatalytic activity was evaluated by the degradation of tetracycline hydrochloride (TCH) under the visible light irradiation. From the photocatalytic activity test, 1% Eu/BiVO4 displayed more superior photodegradation efficiency with 91.4% degradation efficiency of TCH in 150 min by contrast with 77.3% degradation rate of pure BiVO4. The mechanism has been explored that h+ is the primary active species, and ·OH is a secondary active substance in the photocatalytic process.

scholarly journals A Photo-Enzymatic Cascade to Transform Racemic Alcohols into Enantiomerically Pure Amines

Catalysts ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 305 ◽  
Author(s):  
Jenő Gacs ◽  
Wuyuan Zhang ◽  
Tanja Knaus ◽  
Francesco G. Mutti ◽  
Isabel W.C.E. Arends ◽  
...  
Keyword(s):  
Aromatic Compounds ◽  
Reductive Amination ◽  
Aerobic Oxidation ◽  
Secondary Alcohols ◽  
One Pot ◽  
Enantiomerically Pure ◽  
Step Procedure ◽  
Wide Range ◽  
Aldehydes And Ketones ◽  
One Step

The consecutive photooxidation and reductive amination of various alcohols in a cascade reaction were realized by the combination of a photocatalyst and several enzymes. Whereas the photocatalyst (sodium anthraquinone-2-sulfonate) mediated the light-driven, aerobic oxidation of primary and secondary alcohols, the enzymes (various ω-transaminases) catalyzed the enantio-specific reductive amination of the intermediate aldehydes and ketones. The system worked in a one-pot one-step fashion, whereas the productivity was significantly improved by switching to a one-pot two-step procedure. A wide range of aliphatic and aromatic compounds was transformed into the enantiomerically pure corresponding amines via the photo-enzymatic cascade.

Construction of α-alkylated amines by Iridium Complexes-Catalyzed One-Step Transfer Hydrogenation of C=C and C=N Bond

Synthesis ◽  
2020 ◽  
Author(s):  
Yanping Xia ◽  
Lu Ouyang ◽  
Jianhua Liao ◽  
Xiao Yang ◽  
Renshi Luo
Keyword(s):  
Reductive Amination ◽  
Transfer Hydrogenation ◽  
Scale Transformation ◽  
Iridium Complexes ◽  
Practical Application ◽  
One Pot ◽  
System A ◽  
Wide Range ◽  
One Step ◽  
Amine Compounds

Hydrogenation of C=C bond and reductive amination is important transformation utilized in chemistry. An efficient and facile one-pot transfer hydrogenation of C=C bond and reductive amination of C=N bond of enones and amines was reported using the iridium complexes as catalysts and formic acid as hydrogen source in aqueous medium, which shows environmentally friendly. In this catalytic system, a wide range of α-alkylated amine compounds were obtained in excellent yields by one-pot transfer hydrogenation of C=C bond and reductive amination. The practical application of this protocol is characterized by gram-scale transformation.

scholarly journals Simplified Procedure for General Synthesis of Monosubstituted Piperazines—From a Batch Reaction Vessel to a Flow (Microwave) Reactor

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2168
Author(s):  
Dana Němečková ◽  
Eva Havránková ◽  
Jan Šimbera ◽  
Richard Ševčík ◽  
Pavel Pazdera
Keyword(s):  
Protecting Group ◽  
One Pot ◽  
Piperazine Derivatives ◽  
Microwave Reactor ◽  
Synthetic Procedure ◽  
Wide Range ◽  
Synthetic Reactions ◽  
One Step ◽  
Simplified Procedure ◽  
General Synthesis

We reported a novel simplified synthetic procedure for the preparation of monosubstituted piperazine derivatives which can now be easily prepared in a one-pot-one-step way from a protonated piperazine with no need of introduction of a protecting group. Reactions, proceeding either at room or higher temperatures in common solvents, involve heterogeneous catalysis by metal ions supported on commercial polymeric resins. A general synthetic scheme was successfully applied to afford a wide range of monosubstituted piperazines. Furthermore, we picked up a set of piperazine derivatives and studied the possibilities of microwave acceleration of given synthetic reactions to make them even more efficient. Our research proceeded from a simple batch technique to the construction of a flow microwave reactor prototype and resulted in promising findings which are summarized and discussed in the article.

scholarly journals One Pot Synthesis of CoTiO3-TiO2 Composite Nanofibers and its Application in Dye Degradation

2019 ◽  
Vol 8 (2) ◽  
pp. 47-56
Author(s):  
M. Shamshi Hassan
Keyword(s):  
Visible Light ◽  
Composite Nanofibers ◽  
Dye Degradation ◽  
Band Gap Energy ◽  
One Pot ◽  
Light Region ◽  
Electrospinning Method ◽  
One Step ◽  
Ft Ir ◽  
The One

CoTiO3-TiO2 composite nanofibrous photocatalysts were synthesized by means of the one-step electrospinning method. The samples were characterized by a range of different methods (XRD, SEM, EPMA, FT-IR, UV-DRS, and TEM). Photocatalytic activity was performed for the degradation of rhodamine 6G under visible light. The results showed that CoTiO3-TiO2 composite photocatalysts were successfully synthesized. The average sizes of the diameters of the composite nanofibers were found to be 300 to 400 nm. The UV–Vis diffuse reflectance spectra of the CoTiO3-TiO2 composite showed an absorption wavelength, in the visible light region, having a band gap energy value of 2.21 eV. The CoTiO3-TiO2 composite showed higher photocatalytic efficiency than that of pristine TiO2; which can be attributed to the heterojunctional interaction between CoTiO3 and TiO2.

scholarly journals Fusing Carbocycles of Inequivalent Ring Size to a Bis(imino)pyridine-Iron Ethylene Polymerization Catalyst: Distinctive Effects on Activity, PE Molecular Weight, and Dispersity

Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Zheng Wang ◽  
Gregory A. Solan ◽  
Yanping Ma ◽  
Qingbin Liu ◽  
Tongling Liang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ethylene Polymerization ◽  
Bimodal Distribution ◽  
X Ray Diffraction ◽  
One Pot ◽  
Molecular Weights ◽  
Pyramidal Geometry ◽  
Wide Range ◽  
Saturated Chain ◽  
Ft Ir

The 4,6-bis(arylimino)-1,2,3,7,8,9,10-heptahydrocyclohepta[b]quinoline-iron(II) chlorides (aryl = 2,6-Me2C6H3Fe1; 2,6-Et2C6H3Fe2; 2,6-i-Pr2C6H3Fe3; 2,4,6-Me3C6H2Fe4; and 2,6-Et2-4-Me2C6H2Fe5) have been prepared in good yield by a straightforward one-pot reaction of 2,3,7,8,9,10-hexahydro-1H-cyclohepta[b]quinoline-4,6-dione, FeCl2·4H2O, and the appropriate aniline in acetic acid. All ferrous complexes have been characterized by elemental analysis and FT-IR spectroscopy. In addition, the structure of Fe3 has been determined by single crystal X-ray diffraction, which showed the iron center to adopt a distorted square pyramidal geometry with the saturated sections of the fused six- and seven-membered carbocycles to be cis-configured. In combination with either MAO or MMAO, Fe1–Fe5 exhibited exceptionally high activities for ethylene polymerization (up to 15.86×106 gPE mol−1 Fe h−1 at 40°C (MMAO) and 9.60×106 gPE mol−1 Fe h−1 at 60°C (MAO)) and produced highly linear polyethylene (HLPE, Tm≥128°C) with a wide range in molecular weights; in general, the MMAO-promoted polymerizations were more active. Irrespective of the cocatalyst employed, the 2,6-Me2-substituted Fe1 and Fe4 proved the most active while the more sterically hindered 2,6-i-Pr2Fe3 the least but afforded the highest molecular weight polyethylene (Mw: 65.6–72.6 kg mol-1). Multinuclear NMR spectroscopic analysis of the polymer formed using Fe4/MMAO at 40°C showed a preference for fully saturated chain ends with a broad bimodal distribution a feature of the GPC trace (Mw/Mn=13.4). By contrast, using Fe4/MAO at 60°C a vinyl-terminated polymer of lower molecular weight (Mw=14.2 kg mol−1) was identified that exhibited a unimodal distribution (Mw/Mn=3.8). Moreover, the amount of aluminoxane cocatalyst employed, temperature, and run time were also found to be influential on the modality of the polymer.

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

2020 ◽  
Vol 24 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Zita Rádai ◽  
Réka Szabó ◽  
Áron Szigetvári ◽  
Nóra Zsuzsa Kiss ◽  
Zoltán Mucsi ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Room Temperature ◽  
Phase Transfer ◽  
One Pot ◽  
Substrate Dependence ◽  
Triethylbenzylammonium Chloride ◽  
One Step ◽  
The Pudovik Reaction ◽  
The One ◽  
Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

Indium Bromide-catalyzed Unprecedented Hydrogenolysis: A Novel One-Pot Synthesis of Per-O-Acetylated β-carboxymethyl O and S-glycosides

2020 ◽  
Vol 24 (8) ◽  
pp. 900-908
Author(s):  
Ram Naresh Yadav ◽  
Amrendra K Singh ◽  
Bimal Banik
Keyword(s):  
Asymmetric Synthesis ◽  
Chiral Auxiliary ◽  
Bioactive Molecules ◽  
One Pot ◽  
Enantiomerically Pure ◽  
Stereoselective Glycosylation ◽  
One Pot Synthesis ◽  
Wide Range

Numerous O (oxa)- and S (thia)-glycosyl esters and their analogous glycosyl acids have been accomplished through stereoselective glycosylation of various peracetylated bromo sugar with benzyl glycolate using InBr3 as a glycosyl promotor followed by in situ hydrogenolysis of resulting glycosyl ester. A tandem glycosylating and hydrogenolytic activity of InBr3 has been successfully investigated in a one-pot procedure. The resulting synthetically valuable and virtually unexplored class of β-CMGL (glycosyl acids) could serve as an excellent potential chiral auxiliary in the asymmetric synthesis of a wide range of enantiomerically pure medicinally prevalent β-lactams and other bioactive molecules of diverse medicinal interest.

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