Development of Efficient One-Pot Methods for the Synthesis of Luminescent Dyes and Sol–Gel Hybrid Materials

This paper presents a comparison of the simultaneous preparation of di-O-alkylated and ether–ester derivatives of fluorescein using different methods (conventional or microwave heating). Shortening of the reaction time and increased efficiency were observed when using a microwave reactor. Moreover, described here for the first time is the application of a fast, simple, and eco-friendly ball-assisted method to exclusively obtain ether–ester derivatives. We also demonstrate that fluorescein can be effectively functionalized by O-alkylation carried out under microwave or ball-milling conditions, saving time and energy and affording the desired products with good yields and minimal byproduct formation. All the synthesized products as well as pH-dependent (prototropic) forms trapped in the SiO2 matrix were examined using UV–Vis and fluorescence spectroscopy.

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A mesostructured hybrid CTA–silica carrier for curcumin delivery

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-020-05374-0 ◽

2020 ◽

Vol 96 (1) ◽

pp. 236-246

Author(s):

Marta Gallo ◽

Fabio Giudice ◽

Mauro Banchero ◽

Silvia Ronchetti ◽

Luigi Manna ◽

...

Keyword(s):

Water Solubility ◽

Uv Spectroscopy ◽

Sol Gel ◽

Topical Administration ◽

Release Mechanism ◽

Active Principle ◽

One Pot ◽

Drug Release Mechanism ◽

Sol Gel Synthesis ◽

First Time

Abstract Curcumin is a natural active principle with antioxidant, antibacterial and anti-inflammatory properties. Its use is limited by a low water solubility and fast degradation rate, which hinder its bioavailability. To overcome this problem, curcumin can be delivered through a carrier, which protects the drug molecule and enhances its pharmacological effects. The present work proposes a simple one-pot sol–gel synthesis to obtain a hybrid carrier for curcumin delivery. The hybrid consists of a mesostructured matrix of amorphous silica, which stabilizes the carrier, and hexadecyltrimethylammonium (CTA), a surfactant where curcumin is dissolved to increase its water solubility. The carrier was characterized in terms of morphology (FESEM), physicochemical properties (XRD, FTIR, UV spectroscopy) and release capability in pseudo-physiological solutions. Results show that curcumin molecules were entrapped, for the first time, in a silica-surfactant mesostructured hybrid carrier. The hybrid carrier successfully released curcumin in artificial sweat and in a phosphate buffer saline solution, so confirming its efficacy in increasing curcumin water solubility. The proposed drug release mechanism relies on the degradation of the carrier, which involves the concurrent release of silicon. This suggests strong potentialities for topical administration applications, since curcumin is effective against many dermal diseases while silicon is beneficial to the skin.

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Catalyst-Free Three-Component Synthesis of Spirobenzimidazolidines Bearing an Indole Scaffold

Synlett ◽

10.1055/s-0037-1609950 ◽

2018 ◽

Vol 29 (17) ◽

pp. 2301-2305 ◽

Cited By ~ 3

Author(s):

F. Moghaddam ◽

A. Moafi ◽

Z. Zamani ◽

M. Daneshfar

Keyword(s):

Reaction Times ◽

Reaction Conditions ◽

One Pot ◽

Efficient Catalyst ◽

Catalyst Free ◽

New Family ◽

Three Component Reaction ◽

High Yields ◽

First Time ◽

Derivatives Of

An efficient catalyst-free one-pot three-component reaction was developed for the synthesis of a new family of N- and S-containing spirocyclic compounds. Various derivatives of spirobenzimidazolidine containing an indole scaffold were synthesized for the first time in a modestly toxic solvent and under mild reaction conditions. The reaction times were of the order of several minutes, and all the products were obtained in moderate to high yields (overall yields 58–80%).

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New Generation of Hybrid Organic-Inorganic Macrocellular Foams: Integrative Chemistry Toward Reaching Multifunctional Materials

MRS Proceedings ◽

10.1557/proc-1007-s04-06 ◽

2007 ◽

Vol 1007 ◽

Cited By ~ 1

Author(s):

Simona Ungureanu ◽

Hervé Deleuze ◽

Marc Birot ◽

Clément Sanchez ◽

Rénal Backov

Keyword(s):

Sol Gel ◽

Nitrogen Adsorption ◽

Hybrid Networks ◽

Large Set ◽

Porous Network ◽

One Pot ◽

Nitrogen Adsorption Isotherms ◽

New Generation ◽

First Time ◽

Bimodal Porous Structure

ABSTRACTThe elaboration of organosilica based hybrid monoliths exhibiting a hierarchically structured bimodal porous structure with tunable functionality have been processed via High Internal Polymeric Emulsion (HIPE) process for the first time. Through one pot synthesis, many organic functionalities that can act as network modifiers (Methyl, Dinitrophenylamino, Benzyl, Mercaptopropyl) or co-network formers (Pyrrol) have been anchored to the amorphous silica porous network. The resulting materials have been thoroughly characterized via a large set of techniques SEM, TEM, SAXS, mercury porosimmetry, nitrogen adsorption isotherms, FTIR, 29Si MAS NMR. These sol-gel derived hierarchical open cell functional hybrid monoliths exhibit macroscopic void spaces ranging from 5 up to 30 [.proportional]m and their accessible micro-mesoporosity, reveal hexagonal organisation for the dinitrophenylamino, benzyl, and pyrrol based hybrids. The average condensation degree for these hybrid networks ranges between 86 and 90% yielding shaped monoliths with both good integrity and sufficient mechanical properties to be usable as functional catalytic or chromatographic supports.

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Macrocellular Titanosilicate Monoliths as Highly Efficient Structured Olefin Epoxidation Catalysts

10.26434/chemrxiv.7578599 ◽

2019 ◽

Author(s):

Valentin Smeets ◽

Ludivine van den Biggelaar ◽

Tarek Barakat ◽

Eric M. Gaigneaux ◽

Damien Debecker

Keyword(s):

Sol Gel ◽

Silica Matrix ◽

Flow Mode ◽

Tetrahedral Coordination ◽

Excellent Performance ◽

One Pot ◽

Templating Method ◽

Porous Texture ◽

Internal Phase ◽

Epoxidation Of Cyclohexene

Self-standing macrocellular titanosilicate monolith foams are obtained using a one-pot sol-gel route and show excellent performance in the epoxidation of cyclohexene. Thanks to the High Internal Phase Emulsion (HIPE) templating method, the materials feature a high void fraction, a hierarchically porous texture and good mechanical strength. Highly dispersed Ti species can be incorporated in tetrahedral coordination the silica matrix. These characteristics allow the obtained ‘SiTi(HIPE)’ materials to reach high catalytic turnover in the epoxidation of cyclohexene. The monoliths can advantageously be used to run the reaction in continuous flow mode.<br>

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An Expeditious One-Pot Three-Component Synthesis of 4-Aryl-3,4-dihydrobenzo[g] quinoline-2,5,10(1H)-triones under Green Conditions

Current Organic Chemistry ◽

10.2174/1385272823666191108123330 ◽

2020 ◽

Vol 23 (23) ◽

pp. 2626-2634

Author(s):

Saiedeh Kamalifar ◽

Hamzeh Kiyani

Keyword(s):

Reaction Medium ◽

Meldrum's Acid ◽

Meldrum’S Acid ◽

One Pot ◽

One Pot Synthesis ◽

Substituted Benzaldehydes ◽

High Yields ◽

First Time ◽

Green Conditions

: An efficient and facial one-pot synthesis of 4-aryl-3,4-dihydrobenzo[g]quinoline- 2,5,10(1H)-triones was developed for the first time. The process proceeded via the three-component cyclocondensation of 2-amino-1,4-naphthoquinone with Meldrum’s acid and substituted benzaldehydes under green conditions. The fused 3,4-dihydropyridin-2(1H)- one-ring naphthoquinones have been synthesized with good to high yields in refluxing ethanol as a green reaction medium. This protocol is simple and effective as well as does not involve the assistance of the catalyst, additive, or hazardous solvents.

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Synthesis of novel adsorbent based on tetrasulfide-functionalized fibrous silica KCC-1 for removal of Hg(II) cations

Scientific Reports ◽

10.1038/s41598-021-90279-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Azam Marjani ◽

Reza Khan Mohammadi

Keyword(s):

Effective Interaction ◽

Sol Gel ◽

Aqueous Media ◽

Synthesis Method ◽

Mercury Ions ◽

Toxic Heavy Metals ◽

Uptake Capacity ◽

Hydrothermal Preparation ◽

Ultrasonic Assisted ◽

First Time

AbstractHg(II) has been identified to be one of the extremely toxic heavy metals because of its hazardous effects and this fact that it is even more hazardous to animals than other pollutants such as Ag, Au, Cd, Ni, Pb, Co, Cu, and Zn. Accordingly, for the first time, tetrasulfide-functionalized fibrous silica KCC-1 (TS-KCC-1) spheres were synthesized by a facile, conventional ultrasonic-assisted, sol–gel-hydrothermal preparation approach to adsorb Hg(II) from aqueous solution. Tetrasulfide groups (–S–S–S–S–) were chosen as binding sites due to the strong and effective interaction of mercury ions (Hg(II)) with sulfur atoms. Hg(II) uptake onto TS-KCC-1 in a batch system has been carried out. Isotherm and kinetic results showed a very agreed agreement with Langmuir and pseudo-first-order models, respectively, with a Langmuir maximum uptake capacity of 132.55 mg g–1 (volume of the solution = 20.0 mL; adsorbent dose = 5.0 mg; pH = 5.0; temperature: 198 K; contact time = 40 min; shaking speed = 180 rpm). TS-KCC-1was shown to be a promising functional nanoporous material for the uptake of Hg(II) cations from aqueous media. To the best of our knowledge, there has been no report on the uptake of toxic Hg(II) cations by tetrasulfide-functionalized KCC-1 prepared by a conventional ultrasonic-assisted sol–gel-hydrothermal synthesis method.

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Insight into the Secondary Metabolites of Geum urbanum L. and Geum rivale L. Seeds (Rosaceae)

Plants ◽

10.3390/plants10061219 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1219

Author(s):

Marek Bunse ◽

Peter Lorenz ◽

Florian C. Stintzing ◽

Dietmar R. Kammerer

Keyword(s):

Fatty Acids ◽

Phenolic Compounds ◽

Unsaturated Fatty Acids ◽

Asiatic Acid ◽

Cosmetic Products ◽

Nutritional Properties ◽

First Time ◽

Derivatives Of ◽

Geum Urbanum ◽

Insight Into

The present study aimed at the identification and quantitation of phenolic compounds, fatty acids, and further characteristic substances in the seeds of Geum urbanum L. and Geum rivale L. For this purpose, individual components of extracts recovered with MeOH, CH2Cl2, and by cold-pressing, respectively, were characterized by HPLC-DAD/ESI-MSn and GC/MS and compared with reference compounds. For both Geum species, phenolic compounds, such as flavonoids and gallic acid derivatives, and triterpenes, such as saponins and their aglycones, were detected. Surprisingly, both Geum species revealed the presence of derivatives of the triterpenoid aglycons asiatic acid and madecassic acid, which were characterized for the first time in the genus Geum. Furthermore, the fatty acids of both species were characterized by GC–MS after derivatization. Both species showed a promising fatty-acid profile in terms of nutritional properties because of high proportions of unsaturated fatty acids. Linoleic acid and linolenic acid were most abundant, among other compounds such as palmitic acid and stearic acid. In summary, the present study demonstrates the seeds of G. urbanum and G. rivale to be a valuable source of unsaturated fatty acids and bioactive phenolics, which might be exploited for nutritional and cosmetic products and for phytotherapeutic purposes.

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How Can the Introduction of Zr4+ Ions into TiO2 Nanomaterial Impact the DSSC Photoconversion Efficiency? A Comprehensive Theoretical and Experimental Consideration

Materials ◽

10.3390/ma14112955 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2955

Author(s):

Aleksandra Bartkowiak ◽

Oleksandr Korolevych ◽

Gian Luca Chiarello ◽

Malgorzata Makowska-Janusik ◽

Maciej Zalas

Keyword(s):

Density Functional ◽

Sol Gel ◽

Dye Sensitized Solar Cells ◽

Positive Influence ◽

Photoconversion Efficiency ◽

Doped Tio2 ◽

Computational Calculations ◽

Tio2 Nanomaterials ◽

First Time ◽

Sensitized Solar Cells

A series of pure and doped TiO2 nanomaterials with different Zr4+ ions content have been synthesized by the simple sol-gel method. Both types of materials (nanopowders and nanofilms scratched off of the working electrode’s surface) have been characterized in detail by XRD, TEM, and Raman techniques. Inserting dopant ions into the TiO2 structure has resulted in inhibition of crystal growth and prevention of phase transformation. The role of Zr4+ ions in this process was explained by performing computer simulations. The three structures such as pure anatase, Zr-doped TiO2, and tetragonal ZrO2 have been investigated using density functional theory extended by Hubbard correction. The computational calculations correlate well with experimental results. Formation of defects and broadening of energy bandgap in defected Zr-doped materials have been confirmed. It turned out that the oxygen vacancies with substituting Zr4+ ions in TiO2 structure have a positive influence on the performance of dye-sensitized solar cells. The overall photoconversion efficiency enhancement up to 8.63% by introducing 3.7% Zr4+ ions into the TiO2 has been confirmed by I-V curves, EIS, and IPCE measurements. Such efficiency of DSSC utilizing the working electrode made by Zr4+ ions substituted into TiO2 material lattice has been for the first time reported.

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Amino- and sulfo-bifunctionalized hyper-crosslinked organic nanotube frameworks as efficient catalysts for one-pot cascade reactions

New Journal of Chemistry ◽

10.1039/c8nj04514c ◽

2019 ◽

Vol 43 (5) ◽

pp. 2269-2273 ◽

Cited By ~ 3

Author(s):

Guojie Meng ◽

Shengguang Gao ◽

Ying Liu ◽

Li Zhang ◽

Chunmei Song ◽

...

Keyword(s):

Cascade Reactions ◽

One Pot ◽

First Time

The synthesis of amino- and sulfo-bifunctionalized hyper-crosslinked organic nanotube frameworks for one-pot cascade reactions was reported for the first time.

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Identification of pigments in artworks by inverse tangent derivative of spectrum and a new filtering method

Heritage Science ◽

10.1186/s40494-020-00438-4 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

F. Fazlali ◽

S. Gorji Kandi

Keyword(s):

Reflectance Spectrum ◽

Practical Method ◽

Chemical Methods ◽

Munk Function ◽

Absorption Of Light ◽

Spectrophotometric Data ◽

First Time ◽

Non Destructive ◽

Derivatives Of

Abstract Employing an economical and non-destructive method for identifying pigments utilized in artworks is a significant aspect for preserving their antiquity value. One of the non-destructive methods for this purpose is spectrophotometry, which is based on the selected absorption of light. Mathematical descriptive methods such as derivatives of the reflectance spectrum, the Kubelka–Munk function and logarithm have been employed for the characterization of the peak features corresponding to the spectrophotometric data. In the present study, the mentioned mathematical descriptive methods were investigated with the aim to characterize the constituents of an Iranian artwork but were not efficient for the samples. Therefore, inverse tangent derivative equation was developed on spectral data for the first time, providing considerable details in the profile of reflectance curves. In the next part, to have a simpler and more practical method it was suggested to use filters made up of pure pigments. By using these filters and placing them on the samples, imaging was done. Then, images of samples with and without filter were evaluated and pure pigments were distinguished. The mentioned methods were also used to identify pigments in a modern Iranian painting specimen. The results confirmed these methods with reliable answers indicating that physical methods (alongside chemical methods) can also be effective in determining the types of pigments.

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