Further Studies on Ni/Zr-mediated One-pot Ketone Synthesis: Use of a Mixture of NiI- and NiII-catalysts Greatly Improves the Molar Ratio of Coupling Partners

Abstract Silane-functionalized carbon dots (SiCDs) can be exploited as effective color converting materials for the solid-state light-emitting devices. However, most of SiCDs reported thus far have shown photoluminescence emissions in the blue and green spectral range, which limit them to construct an efficient white light-emitting diodes (WLEDs) due to the lack of long-wavelength emission. Herein, a series of double silane-functionalized carbon dots (DSiCDs) were prepared via a one-step solvothermal method. The results show that the organic functional group of the silane has great influence on the optical properties of DSiCDs and the number of alkoxy group in the silane has great influence on coating properties of DSiCDs. In addition, the DSiCDs prepared by (3-aminopropyl)triethoxysilane and N-[3-(Trimethoxysilyl)propyl]ethylenediamine with molar ratio of 7:3 show excellent optical properties with the maximum emission at 608 nm under 400 nm excitation. Furthermore, they can be completely dried within 1 h at room temperature to form fluorescent coating with high stability and strong adhesion to the substrate. Together with their excellent optical and coating properties, they can be directly coated on LED chips to prepare WLEDs, with a CIE coordinate of (0.33,0.31), color rendering index of 81.6, and color temperature of 5774 K.

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One-pot synthesis of the new Hydroxamic acid and its complexes with metals

Letters in Organic Chemistry ◽

10.2174/1570178619666220111121743 ◽

2022 ◽

Vol 19 ◽

Author(s):

Gulu Abbasova ◽

Ajdar Medjidov

Keyword(s):

Nmr Spectroscopy ◽

Thermogravimetric Analysis ◽

Hydroxamic Acid ◽

Uv Spectroscopy ◽

Molar Ratio ◽

One Pot ◽

Ethanol Medium ◽

Physicochemical Methods ◽

Colored Complexes ◽

First Time

Abstract: A one-pot conversion of 2-hydroxy-1-naphthoic aldehyde to hydroxamic acid was described. An efficient photoorganocatalytic method of synthesis was developed. The obtained hydroxamic acid was identified by various physicochemical methods such as IR, UV- and NMR-spectroscopy. Solid colored complexes of copper (II) and iron (II), respectively, green and brown colours with the obtained hydroxamic acid were synthesized in ethanol medium for the first time. The molar ratio of ligand and metal in the complex was 2:1. Their structures were established using IR, UV- spectroscopy and thermogravimetric analysis.

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One-Pot Synthesis of Coral-Shaped Gold Nanostructures for Surface-Enhanced Raman Scattering

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.14.47 ◽

2011 ◽

Vol 14 ◽

pp. 47-55 ◽

Cited By ~ 6

Author(s):

Jian Hui Yang ◽

Dhiraj K. Sardar

Keyword(s):

Raman Scattering ◽

Ethylenediaminetetraacetic Acid ◽

Chelating Agent ◽

Surface Enhanced Raman Scattering ◽

Gold Nanostructures ◽

Molar Ratio ◽

One Pot ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering

In this work, a chelating agent, ethylenediaminetetraacetic acid (EDTA) was used for the controllable synthesis of gold nanostructures in aqueous solution. Coral-shaped Au nanostructures were synthesized by reducing HAuCl4 with EDTA. EDTA serves not only as a reducing agent but also as a particle capping agent in the formation of coral-shaped Au nanostructures. It is found that the molar ratio of HAuCl4:EDTA and reacted temperature play significant effects on the formation and growth of these novel nanostructures. These Au nanostructures could serve as highly sensitive and reproductive surface-enhanced Raman scattering (SERS) substrates for chemical and biological detection.

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Single-Component White Light Emitting CdSexSy Alloy Nanocrystals Through Phosphine-Free Route

10.26434/chemrxiv.12643475.v1 ◽

2020 ◽

Author(s):

Shilpi Jaiswal ◽

Jyotsana Pathak ◽

Abhijit Patra

Keyword(s):

Quantum Yield ◽

White Light ◽

Light Emission ◽

Semiconductor Nanocrystals ◽

White Light Emission ◽

Molar Ratio ◽

Visible Range ◽

One Pot ◽

Light Emitting ◽

Hydrogel Matrix

Semiconductor nanocrystals are promising for display and lighting devices. Herein, we report a facile one-pot synthetic route to fabricate white light emitting CdSexSy nanocrystals with enhanced quantum yield using CdO, S powder, and Se powder as precursors. The phosphine-free route was adopted, employing paraffin oil as the reducing agent and solvent for the fabrication. The optical properties can be effectively tailored by controlling the reaction time and the molar ratio of Se/S. The emission of pristine CdSexSy nanocrystals covered a broad visible range from 400 to 750 nm. The CdSexSy nanocrystals (Se/S = 0.4) exhibited white-light emission with quantum yield of 50 ± 3 % and Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of (0.30, 0.31). The band-edge (~400-450 nm) to trap-state (~550-750 nm) emissions was tuned by controlling the Se/S ratio, and the different shades of white light were obtained. Furthermore, the quantum yield and CIE coordinates of the CdSexSy nanocrystals (Se/S = 0.4) were found to be similar even after 30 days of fabrication, showing the high stability of nanocrystals. The white light emission was retained in nanocrystals-embedded poly(methyl methacrylate) (PMMA) thin film and also in the hydrogel matrix. The one-pot, low-cost, scalable fabrication of white light emitting CdSexSy nanocrystals demonstrated in the present study offers promising scope in the solid-state display applications. <br>

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One-Pot Preparation of Metal–Polymer Nanocomposites in Irradiated Aqueous Solutions of 1-Vinyl-1,2,4-triazole and Silver Ions

Polymers ◽

10.3390/polym13234235 ◽

2021 ◽

Vol 13 (23) ◽

pp. 4235

Author(s):

Alexey A. Zezin ◽

Alexey A. Zharikov ◽

Artem I. Emel’yanov ◽

Alexander S. Pozdnyakov ◽

Galina F. Prozorova ◽

...

Keyword(s):

Aqueous Solutions ◽

Monomer Concentration ◽

Gel Permeation Chromatography ◽

Silver Ions ◽

Polymer Nanocomposite ◽

Molar Ratio ◽

One Pot ◽

Radiation Chemical ◽

Vis Spectroscopy ◽

Metal Polymer

Metal–polymer nanocomposite polyvinyltriazole–silver nanoparticles were obtained using one-pot synthesis in irradiated aqueous solutions of 1-vinyl-1,2,4-triazole (VT) and silver ions. Gel permeation chromatography data show that upon radiation initiation, the molecular weight of poly(1-vinyl-1,2,4-triazole) increases with increasing monomer concentration. To study the kinetics of polymerization and the features of the radiation–chemical formation of nanoparticles, UV-Vis spectroscopy was used. TEM images show a relatively small average size of the forming nanoparticles (2–3 nm) and a narrow size distribution, which shows the effective stabilization of nanoparticles by triazole substituents at a molar ratio of VT and silver ions of 25/1. The addition of ethyl alcohol was used to increase the efficiency of synthesis and suppress the crosslinking of macromolecules in solution. The results of the work show that aqueous–alcoholic solutions of 1 wt.% VT can be used to obtain soluble nanocomposite materials. 10 wt.% monomer solutions have prospects for use in the preparation of polymer gels filled with nanoparticles.

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New Facile One-Pot Synthesis of Isobutyl Thiocarbamate in Recycling Solvent Mixture

Minerals ◽

10.3390/min11121346 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1346

Author(s):

Goran Milentijević ◽

Aleksandar D. Marinković ◽

Milica Rančić ◽

Aleksandra Bogdanović ◽

Nevena Prlainović ◽

...

Keyword(s):

Industrial Production ◽

Simple Procedure ◽

Solvent Mixture ◽

Molar Ratio ◽

Conversion Degree ◽

Green Technologies ◽

One Pot ◽

Efficiency Test ◽

Gas Chromatographic Method ◽

Instrumental Methods

The specific objectives of the presented study were related to the optimization of the production process of N-alkyl-, N,N-dialkyl-, and N-cycloalkyl-O-isobutyl thiocarbamate; trial industrial production of N-ethyl-O-isobutyl thiocarbamate; and the evaluation of flotation efficiency of N-ethyl-O-isobutyl thiocarbamate using a real ore sample. The optimization of thiocarbamate syntheses were performed by varying the molar ratio of isobutyl alcohol, carbon disulfide, potassium hydroxide, reaction time, and reaction temperature. In the first step, one-pot reaction took place to produce alkyl xanthate and was followed with chlorination to give alkyl chloroformate (O-alkyl carbonochloridothioate); finally, thiocarbamates were obtained by the reaction with corresponding amines. N-alkyl-O-ethyl thiocarbamate was synthesized as a comparative flotation agent. The structure of the synthesized compounds was confirmed by IR, 1H and 13C NMR, and MS instrumental methods, and the purity was determined by gas chromatographic method and elemental analysis. The optimized methods gave high-purity products in a significant yield that was also confirmed by semi-industrial production of N-ethyl-O-isobutyl thiocarbamate. The optimized thiocarbamate synthesis, without isolation of intermediates, is of great importance from the aspect of green technologies. Flotation efficiency test results, using real copper and zinc ores, showed the highest activity of N-ethyl-O-isobutyl thiocarbamate. The optimal one-pot thiocarbamate synthesis provides a simple procedure with a high conversion degree, and, thus, offers valuable technology applicable at the industrial scale.

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Hyperbranched unsaturated polyester amide synthesized by two-step method

Pigment & Resin Technology ◽

10.1108/prt-04-2017-0044 ◽

2019 ◽

Vol 48 (1) ◽

pp. 29-35

Author(s):

Hongjuan Zheng ◽

Weiqiang Song

Keyword(s):

Molecular Weight ◽

Rheological Properties ◽

Unsaturated Polyester ◽

Molar Ratio ◽

Synthesis Process ◽

Step Method ◽

One Pot ◽

Content Type ◽

Hyperbranched Poly ◽

Practical Implications

PurposeHyperbranched poly(ester-amide)s (HPEAs) have been synthesized from diethanolamine and maleic anhydride with ethylene glycol as a core monomer by using a two-step method, which are marked as Hupea polymers, and dehydration was carried out in xylene under reflux.Design/methodology/approachIn comparison with Hupea polymers was synthesized by one-pot method, Hupea polymers synthesized by two-step method has different structure and rheological properties. The intermediate monomer and the resulting polymer are characterized by FTIR and NMR spectroscopies.FindingsAll of Mw, Mn and Mw/Mn of the hyperbranch polymers decrease with the core/monomer molar ratio increasing. The intrinsic viscosity ([η]) of the polymers decreases with Mw increasing in the investigated range of Mw and scales as [η]∼Mw-0.82, which implies that the molecular weight grew faster with core/monomer molar ratio decreasing than the volume in the investigated range of core/monomer molar ratio.Research limitations/implicationsThe hydrodynamic radius was calculated by using Einstein’s equation and scales as Rh ∼ Mw0.061, and the lower exponent reveals the slow growth in the volume of Hupea molecule. In addition, the viscosity of Hupea polymer in concentrated aqueous solution is independent of shear rate and slightly dependent on molecular weight.Practical implicationsHyperbranched poly(ester-amide)s (HPEAs) were synthesized by using a two-step method, which had different structure and rheological properties.Originality/valueHupea polymers show different features from Hupea polymers in structure and rheological properties, which revealed that the synthesis process of HPEA has effect on its performance.

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Enhancement of toluene removal over α@δ-MnO2 composites prepared via one-pot by modifying the molar ratio of KMnO4 to MnSO4·H2O

Applied Surface Science ◽

10.1016/j.apsusc.2021.150972 ◽

2021 ◽

pp. 150972

Author(s):

Xin Min ◽

Mingming Guo ◽

Kan Li ◽

Jia-nan Gu ◽

Xin Guo ◽

...

Keyword(s):

Molar Ratio ◽

One Pot ◽

Toluene Removal

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Influence of Carbon Content in Ni-Doped Mo2C Catalysts on CO Hydrogenation to Mixed Alcohol

Catalysts ◽

10.3390/catal11020230 ◽

2021 ◽

Vol 11 (2) ◽

pp. 230

Author(s):

Zhenjiong Hao ◽

Xiaoshen Li ◽

Ye Tian ◽

Tong Ding ◽

Guohui Yang ◽

...

Keyword(s):

Carbon Content ◽

Co Hydrogenation ◽

Nickel Content ◽

Active Surface ◽

Dissociative Adsorption ◽

Molar Ratio ◽

Active Surface Area ◽

Low Carbon ◽

Ni Doping ◽

One Pot

Herein, we synthesize the Ni-doped Mo2C catalysts by a one-pot preparation method to illuminate the effect of the number of carbon atoms in Mo2C lattice on CO hydrogenation to mixed alcohol. The Ni doping inhibits the agglomeration of Mo2C crystals into large particles and the surface carbon deposition, which increase the active surface area. In addition, the interaction between Ni and Mo increases the electron cloud density of Mo species and promotes the non-dissociative adsorption and insertion of CO. Especially, our results indicate that with the increase of the nickel content, the number of carbon atoms in Mo2C lattice on the surface of the catalyst shows a volcano type variation. The low carbon content induces the formation of coordination unsaturated molybdenum species which exhibit the higher catalytic activity and mixed alcohol selectivity than other molybdenum species. Among the catalysts, the MC-Ni-1.5 catalyst with Ni/Mo molar ratio of 1.5:8.5, which has the largest amount of coordination unsaturated molybdenum species, shows the highest space-time yield of mixed alcohols, which is three times higher than that of the Mo2C catalyst.

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Simple One Pot Preparation of Chemical Hydrogels from Cellulose Dissolved in Cold LiOH/Urea

Polymers ◽

10.3390/polym12020373 ◽

2020 ◽

Vol 12 (2) ◽

pp. 373 ◽

Cited By ~ 3

Author(s):

Jiayi Yang ◽

Bruno Medronho ◽

Björn Lindman ◽

Magnus Norgren

Keyword(s):

Molar Ratio ◽

Cross Linking ◽

Absorption Properties ◽

One Pot ◽

Molar Ratios ◽

Cellulose Pulp ◽

Water Uptake Capacity ◽

Swelling Capacity ◽

Cellulose Hydrogel ◽

Water Swelling

In this work, non-derivatized cellulose pulp was dissolved in a cold alkali solution (LiOH/urea) and chemically cross-linked with methylenebisacrylamide (MBA) to form a robust hydrogel with superior water absorption properties. Different cellulose concentrations (i.e., 2, 3 and 4 wt%) and MBA/glucose molar ratios (i.e., 0.26, 0.53 and 1.05) were tested. The cellulose hydrogel cured at 60 °C for 30 min, with a MBA/glucose molar ratio of 1.05, exhibited the highest water swelling capacity absorbing ca. 220 g H2O/g dry hydrogel. Moreover, the data suggest that the cross-linking occurs via a basic Michael addition mechanism. This innovative procedure based on the direct dissolution of unmodified cellulose in LiOH/urea followed by MBA cross-linking provides a simple and fast approach to prepare chemically cross-linked non-derivatized high-molecular-weight cellulose hydrogels with superior water uptake capacity.

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