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Journal articles on the topic 'Keywords: Solvent-free reactions'

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Published: 7 June 2025

Last updated: 2 August 2025

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1

Away, Kenneth Charles West, and Zhu-Gen Lai. "Solvent effects on SN2 transition state structure. II: The effect of ion pairing on the solvent effect on transition state structure." Canadian Journal of Chemistry 67, no. 2 (1989): 345–49. http://dx.doi.org/10.1139/v89-056.

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Identical secondary α-deuterium kinetic isotope effects (transition state structures) in the SN2 reaction between n-butyl chloride and a free thiophenoxide ion in aprotic and protic solvents confirm the validity of the Solvation Rule for SN2 Reactions. These isotope effects also suggest that hydrogen bonding from the solvent to the developing chloride ion in the SN2 transition state does not have a marked effect on the magnitude of the chlorine (leaving group) kinetic isotope effects. Unlike the free ion reactions, the secondary α-deuterium kinetic isotope effect (transition state structure) f

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2

Roopa, Redamala*. "UNDER SOLVENT-FREE CONDITIONS, ACETYLATION and VILSMEIER-HAACK FORMYLATION REACTIONS WITH ACETANILIDES and ANILINES." Journal of Pharma Research 11, no. 06 (2022): 72–84. https://doi.org/10.5281/zenodo.7813300.

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Abstract:  <strong>The Vilsmeier-Haack reaction with anilines and acetanilides was carried out without the use of a solvent. At room temperature, the reactants are put in a mortar and ground with a pestle for 20 to 30 minutes. Formyl derivatives were generated in surprisingly good yields when dimethyl formamide (DMF) and POCl3 were used as the VH reagent. Nevertheless, acetyl derivatives were generated when DMF was substituted for DMA in the formulation of the VH reagent. The results of solvent free reactions are better to those of solution phase reactions, with high yields and much short

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3

Gadhave, Anil G., Sanket B. Shirsath, Amol R. Parhad, Bhagwat K. Uphade, and Dilip S. Aute. "Green and efficient synthesis of 2H-indazolo[2,1-b]phthalazine-triones using PPA-polyborate under solvent-free conditions." INDIAN JOURNAL OF HETEROCYCLIC CHEMISTRY 35, no. 02 (2025): 501. https://doi.org/10.59467/ijhc.2025.35.501.

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Polyphosphoric acid (PPA)-polyborate as a solid acid new catalyst was prepared by the reaction between PPA and polyborate. 2H-Indazolo[2,1-b]phthalazine-1,6,11(13H)-triones were synthesized under solvent-free conditions through one-pot tri-component reaction involving substituted aryl aldehydes, phthalhydrazide, and dimedone in the presence of PPA-polyborate catalyst. The main advantages of this study are good to excellent yields, use of less hazardous chemical, shorter reaction times, gentler reaction conditions, reduced chemical waste, increased energy efficiency, environmentally friendly pa

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4

Lai, Zhu-Gen, and Kenneth Charles Westaway. "Isotope effects in nucleophilic substitution reactions. VII. The effect of ion pairing on the substituent effects on SN2 transition state structure." Canadian Journal of Chemistry 67, no. 1 (1989): 21–26. http://dx.doi.org/10.1139/v89-004.

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The secondary α-deuterium kinetic isotope effects and substituent effect found in the SN2 reactions between a series of para-substituted sodium thiophenoxides and benzyldimethylphenylammonium ion are significantly larger when the reacting nucleophile is a free ion than when it is a solvent-separated ion pair complex. Tighter transition states are found when a poorer nucleophile is used in both the free ion and ion pair reactions. Also, the transition states for all but one substituent are tighter for the reactions with the solvent-separated ion pair complex than with the free ion. Hammett ρ va

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5

Rodriguez, Amalia, Francisco Sánchez Burgos, John Burgess, and Carmen Carmona. "Medium effect on reactions between anions carrying different charges." Canadian Journal of Chemistry 68, no. 6 (1990): 926–31. http://dx.doi.org/10.1139/v90-144.

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The reactions between hexacyanoferrate(II)–peroxodisulphate, hexacyanoferrate(III)–sulphite, hexacyanoferrate(III)–iodide and peroxodisulphate–iodide have been studied in methanol–water mixtures at different methanol concentrations. The results have been analyzed using different approaches, namely electrostatic theory, the δμθ initial state – transition state analysis, the decomposition of free energy of activation into enthalpic and entropic terms and, finally, correlation between reactivity and the Grunwald–Winstein parameter, Y. The four reactions show similar behaviour and a correlation be

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6

Upadhyay, Saurabh Kumar, Prof (Dr.) Vikas Verma, Prof (Dr.) Ashish Vishwakarma, and Dr. Shailendra Kumar Dubey. "Advances in Solvent-Free Synthesis: Environmental Impact and Applications in Medicinal Chemistry." International Journal of Advance and Applied Research 12, no. 2 (2024): 296–303. https://doi.org/10.5281/zenodo.14650284.

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<strong>Abstract</strong> This study investigates the impact of solvent-free synthesis methods on medicinal chemistry, emphasizing their role in promoting sustainability and innovation. Using secondary data analysis, the research evaluates the efficiency, mechanisms, and environmental benefits of solvent-free reactions in synthesizing biologically active compounds. Results highlight the effectiveness of techniques such as microwave-assisted synthesis and mechanochemical activation in reducing chemical hazards and energy consumption. The study identifies applications in drug development, energy

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7

Bolton, Judy L., and Robert A. McClelland. "Azide ion trapping and lifetime in aqueous solution of a primary carbenium ion stabilized by a 2-imidazoyl ring." Canadian Journal of Chemistry 67, no. 7 (1989): 1139–43. http://dx.doi.org/10.1139/v89-171.

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2-Chloromethyl-1-methylimidazole undergoes a pH-dependent aqueous hydrolysis with the neutral substrate being the reactive species, and the imidazole-protonated form (pKa = 5.7) unreactive. Addition of sodium chloride retards the hydrolysis, evidence that there is a free carbenium ion intermediate (the common ion effect). The rate constant ratio Kcl/Kw for the reactions of this cation with the added chloride and with the solvent is 7.4 M−1. Further evidence for a free cation is the observation of the 2-azidomethyl product when the hydrolysis is carried out with sodium azide present, but with n

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8

Jeong, Minji, Jaehong Lim, and Si Hyoung Oh. "Safe Solvent-in-Salt Electrolytes for Dendrite-Free Zinc Metal Batteries." ECS Meeting Abstracts MA2023-02, no. 4 (2023): 614. http://dx.doi.org/10.1149/ma2023-024614mtgabs.

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As global markets for electric vehicles (EV) and energy storage systems (ESS) expand rapidly, there are growing needs to develop alternative battery systems to replace current lithium-ion battery (LIBs) technology, which suffers from high material cost, and insufficient safety. Rechargeable zinc batteries have emerged as one of the most viable and sustainable candidates to replace LIB owing to various beneficial features of zinc such as natural abundance, easy recyclability (by electrowinning), high safety and high volumetric capacity (5,854 Ah/L) compared with lithium (2,062 Ah/L). However, p

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9

TRIPATHEE, NEHA. "Schiff Bases in Environmental Science: Approaches to Pollution Management." WORLD JOURNAL OF APPLIED SCIENCE AND RESEARCH 12-13, no. 01-02 (2023): 67. https://doi.org/10.59467/wjasr.2022-23.12-13.67.

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Schiff bases (SBs), characterized by the imine (-C=N-) group, have gained prominence for their versatility and environmental significance. Their synthesis aligns with green chemistry principles, employing eco-friendly solvents, catalysts, and techniques such as solvent-free reactions, ball milling, and biocatalysis. SBs demonstrate remarkable utility in pollution control applications, including wastewater treatment, heavy metal removal, dye degradation, and pesticide adsorption. They act as efficient chelating agents, photocatalysts, and corrosion inhibitors, offering sustainable solutions to

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10

Abera Negesse, Getachew, Mesfin Diro Chaka, Desalegn Nigatu Gemechu, et al. "Uncovering benzoquinone derivatives for redox flow batteries: DFT insights on reduction potentials and solvent effects." Bulletin of the Chemical Society of Ethiopia 39, no. 2 (2024): 381–96. http://dx.doi.org/10.4314/bcse.v39i2.15.

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Quinones possess high redox potential, making them suitable for organic redox-flow batteries. Their oxidation and discharge during charging involve two reversible electron transfer reactions. This study utilized density functional theory (DFT) with the B3LYP functional and 6-31G(d) basis set to calculate the first and second reduction potentials of benzoquinones (BQ). Various BQ derivatives were created by adding electron-donating substituents (-NHCH3, -NH2, -OCH3, -NHCOCH3, -OCOCH3). The universal solvation model (SMD) assessed solvent effects, while lithium salts, solvation-free energy, and

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11

Fatimə Novruzova, Fatimə Novruzova, Khuraman Hajiakhmedzade Khuraman Hajiakhmedzade, Esfira Bagirova Esfira Bagirova, and Irina Akhmedova Irina Akhmedova. "INFLUENCE OF ADDITIONAL INHIBITORS ON CATALYTIC DESTRUCTION REACTION OF POLYISOBUTYLENE." PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 12, no. 01 (2022): 115–22. http://dx.doi.org/10.36962/pahtei12012022115.

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It is impossible to create a scientific basis for the synthesis of polymers without taking into account the destruction process. Under the action of Lewis acids, the destruction of PIB follows a free radical chain mechanism, while the catalytic destruction of PIB leads to the formation of both linear and branched macromolecules. The most wide-spread type of chemical destruction is an oxidative destruction by oxygen and ozone. The oxidative destruction is activated by heat, light rays and mechanical energy, and the types of thermal, photo and mechanical oxidative destruction are known, respecti

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12

Pregel, Marko J., Edward J. Dunn, and Erwin Buncel. "Metal ion catalysis in nucleophilic displacement reactions at carbon, phosphorus, and sulfur centers. III. Catalysis vs. inhibition by metal ions in the reaction of p-nitrophenyl benzenesulfonate with ethoxide." Canadian Journal of Chemistry 68, no. 10 (1990): 1846–58. http://dx.doi.org/10.1139/v90-287.

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The rate of the nucleophilic displacement reaction of p-nitrophenyl benzenesulfonate (1) with alkali metal ethoxides in ethanol at 25 °C has been studied by spectrophotometric techniques. For lithium ethoxide, sodium ethoxide, potassium ethoxide, and cesium ethoxide, the observed rate constants increase in the order LiOEt < NaOEt < CsOEt < KOEt. The effect of added crown ether and cryptand complexing agents was also investigated. Addition of complexing agent to the reaction of KOEt results in the rate decreasing to a minimum value corresponding to the reaction of free ethoxide. Conver

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13

Ulaan, Gia Aprilia Kartini, Adithya Yudistira, and Henki Rotinsulu. "UJI AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL ALGA Ulva lactuca MENGGUNAKAN METODE DPPH (1,1 diphenyl-2-picrylhydrazyl)." PHARMACON 8, no. 3 (2019): 535. http://dx.doi.org/10.35799/pha.8.2019.29327.

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Ulva lactuca Algae habitat was found in shallow marine waters and its morphology is thin and flat thallus. Ulva lactuca Algae, known as sea lettuce, contains a lot of chlorophyll in its cells. Chlorophyll has the ability as a free radical scavenger and also has antioxidant activity. Antioxidants are compounds that could inhibit oxidation reactions by binding to free radicals and highly reactive molecules. This study was conducted to determine the antioxidant activity of ethanol extract of Algae Ulva lactuca obtained from the Lembeh Strait, Bitung City. Ulva lactuca Algae was extracted by macer

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14

Gurumeet, C. Wadhawa 1. *. Harshada Deshmukh 2. Vitthal S. Shivankar 3. Yashwant A. Gaikwad 4. "ONE-POT SYNTHESIS OF THE COUMARINE UNDER GREEN APPROACH USING FERROUS SULPHATE AS CATALYST." Journal of Pharma Research 8, no. 4 (2019): 132–35. https://doi.org/10.5281/zenodo.2647854.

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<strong><em>ABSTRACT</em></strong> <strong><em>S</em></strong><em>ynthesis of various substituted Coumarins from substituted phenol and β-ketoester (Ethyl Acetoacetate) via Pechmann condensation using heterogeneous catalyst like red mud solvent free condition under sonication. Reaction required low reaction time, very mild reaction condition, at room temperature and easy workup with good yield of the product.</em> <strong><em>KEYWORDS:</em></strong><em> Coumarins, Pechmann condensation, Solvent free reaction, Sonication.</em>

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15

Liao, Cheng Hung, Chia-Chin Chen, Ru-Jong Jeng, and Nae-Lih (Nick) Wu. "Application of Artificial Interphase on Ni-Rich Cathode Materials Via Hybrid Ceramic-Polymer Electrolyte in All Solid State Batteries." ECS Meeting Abstracts MA2023-01, no. 6 (2023): 1050. http://dx.doi.org/10.1149/ma2023-0161050mtgabs.

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Among many cathode materials, nickel-rich LiNi0.83Co0.12Mn0.05O2 (NCM 831205) has been spotlighted as one of the most feasible candidates for next-generation LIBs because of its high discharge capacity (~200 mAh/g). However, NCM 831205 shows significant performance degradation, which is mostly attributed to cation mixing, surface side reactions, and intrinsic structural instability originating from the large volume changes during repeated cycling. Conventional lithium ion batteries (LIB) normally use flammable nonaqueous liquid electrolytes, resulting in a serious safety issue in use. In this

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16

Rajput, P., N. J. P. Subhashini, and Shiva Raj. "Synthesis of 2,4,6-triarylpyridines Using AlPO₄ Under Solvent-free Conditions." Journal of Scientific Research 2, no. 2 (2010): 337–42. http://dx.doi.org/10.3329/jsr.v2i2.3859.

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A series of 2,4,6-triarylpyridines have been prepared using a variety of aromatic and heteroaromatic aldehydes in the presence of aluminum phosphate (AlPO4) as a heterogeneous catalyst at 120 oC under solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, shorter reaction times, milder conditions and the catalyst exhibited remarkable reusable activity. Keywords: Aluminum phosphate; 2,4,6-triarylpyridines; One-pot synthesis; Shorter reaction times; Reusable activity. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Onli

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17

Balón, Manuel, and Carmen Carmona. "The simultaneous influence of organic solvent and salt on the iodide-peroxodisulphate reaction." Canadian Journal of Chemistry 68, no. 3 (1990): 483–87. http://dx.doi.org/10.1139/v90-074.

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To study the additivity of medium effects, the rates of reaction between peroxodisulphate and iodide ions have been measured in several salt – water – organic solvent mixtures. The results are consistent with Symons 's hypothesis of the influence of salts and organic solvents on the equilibrium between bound water, free OH, and lone pair groups. Keywords: medium effects, kinetics, iodide, peroxodisulphate.

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18

Mane, Vishal, and Dhanjay Mane. "[DBN][HSO4]-Promoted facile and green synthesis of 2-Amino-4H-pyrans derivatives under microwave irradiation." Journal of Drug Delivery and Therapeutics 11, no. 2-S (2021): 89–97. http://dx.doi.org/10.22270/jddt.v11i2-s.4824.

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The [DBN][HSO4] -promoted Knoevenagel condensation followed by cyclization protocol has been developed for the first time by a successive reaction of aldehydes, dimedone and malononitrile to afford 2-Amino-4H-pyrans derivatives in high to excellent yields at room temperature. The synergic couple of microwave and ionic liquid provided the capability to allow a variability of functional groups, short reaction times, easy workup, high yields, recyclability of the catalyst, and solvent-free conditions, thus providing economic and environmental advantages. Keywords: [DBN][HSO4], Environmental

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19

Rudyanto, Marcellino, and Lanny Hartanti. "ONE-STEP CONVERSION OF EUGENOL TO METHYL ISOEUGENOL USING MICROWAVE IRRADIATION IN SOLVENT-FREE CONDITIONS." Indonesian Journal of Chemistry 6, no. 3 (2010): 292–96. http://dx.doi.org/10.22146/ijc.21734.

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A research on conversion of eugenol to methyl isoeugenol via one-step reaction with microwave irradiation has been carried out. Mixtures containing eugenol, sodium or potassium carbonate as solid support, with or without sodium or potassium hydroxide as base, with or without tetrabutylammonium bromide as phase transfer catalyst, with dimethyl sulfate as the methylating agent were irradiated in a domestic microwave oven for 20 - 50 seconds. It was revealed that one-step methylation and isomerization required combinations of sodium or potassium hydroxide base and tetrabutylammonium bromide. With

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20

National, Press Associates. "SYNTHESIS OF IMIDAZOLE." Research & Reviews in Biotechnology & Biosciences 11, no. 1 (2024): 44–49. https://doi.org/10.5281/zenodo.14605027.

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A simple approach was used to prepare concentrated nitric acid supported on nano silica (HNO3@nanoSiO2). The synthetic powder was used as an efficient catalytic system for the synthesis of different 2,4,5-trisubstituted imidazoles in good to outstanding yields under solvent-free conditions at 100 C. Furthermore, 1,2,4,5-tetrasubstituted imidazoles have been successfully performed under the same reaction conditions. In three runs, the recovery and reusability of HNO3@nano SiO2 were tested without activity loss. In the reported technique, the main properties of this acidic Nano catalyst include

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21

Galezowski, Wlodzimierz, and Arnold Jarczewski. "Study of the dissociation of the products of some proton transfer reactions in acetonitrile solvent." Canadian Journal of Chemistry 70, no. 3 (1992): 935–42. http://dx.doi.org/10.1139/v92-126.

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The conductometric study of the products of the proton transfer reactions of C-acids (nitriles, nitroalkanes, and 2,4,6-trinitrotoluene) with the strong amine bases (1,1,3,3-tetramethylguanidine (TMG), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,8-bis(dimethylamino)naphthalene (DMAN), and piperidine) in acetonitrile shows their large degree of dissociation into free ions. The dissociation constant values have been estimated at 25 °C to be larger than 1 × 10−4 M. This weakens the formalism commonly accepted in spectrophotometric kinetic studies of these systems of reactions, based on the assump

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22

Teja, V. Ravi, G. Giribabu, and Dr N. Krishnarao. "An Efficient Synthesis of 2, 4, 5-Triphenyl Imidazole Derivatives Promoted By Mg (NO3)2." INTERANTIONAL JOURNAL OF SCIENTIFIC RESEARCH IN ENGINEERING AND MANAGEMENT 09, no. 04 (2025): 1–9. https://doi.org/10.55041/ijsrem43650.

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A simple, highly versatile and an efficient synthesis of 2, 4, 5-trisubstituted imidazole that was obtained by three component cyclocondensation of benzil, substituted aromatic aldehydes and ammonium acetate in solvent free condition using Mg (NO3)2 acts as catalyst. The main advantages of this method of process are cost effectiveness of catalyst, easy work-up and purification of products by non-chromatographic methods, good to excellent yields and very short reaction time. The newly synthesized derivatives were evaluated by advanced spectroscopic data such as 1HNMR, 13CNMR and LCMS and the st

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23

Jaiswal, Shalini, and Smriti Dwivedi. "Microwave-assisted Eco-Friendly Synthesis and Antimicrobial Evaluation of Aryl-Triazole-1,3,4-Thiadiazols." Journal of Medical Research and Innovation 1, no. 3 (2017): 17–22. http://dx.doi.org/10.15419/jmri.51.

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Due to the growing awareness about environmental pollution and environmental legislation, recent years have witnessed a phenomenal increase in the application of microwave irradiation (MW) in organic synthesis. Heterocyclic compounds are abundant in nature and are of great significance to life because their structural subunits exist in many natural products such as vitamins, hormones, and antibiotics; hence, they have attracted considerable attention in the design of biologically active molecules and advanced organic chemistry. The application of molecular diversity technique to drug discovery

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Widiyarti, Galuh, Muhammad Hanafi, and Wahyudi Priyono Soewarso. "STUDY ON THE SYNTHESIS OF MONOLAURIN AS ANTIBACTERIAL AGENT AGAINTS Staphylococcus aureus." Indonesian Journal of Chemistry 9, no. 1 (2010): 99–106. http://dx.doi.org/10.22146/ijc.21569.

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The monolaurin compound had been synthesized from lauric acid and glycerol by using sulfuric acid (H2SO4) as catalyst. The synthesis of monolaurin was done by batch esterification on the free solvent system. The esterification reaction was performed on the equivalent mol ratio between lauric acid and glycerol 1:1, in the presence of 5% H2SO4, at 130 °C, for 6 hours, produced ester compounds on 59.29%. The products of column chromatography on silica gel purification are monolaurin and dilaurin in amount of 31.05 and 4.48%, respectively. The monolaurin and dilaurin were identified by TLC, FTIR,

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25

Ghodrat Mahmoudi, Ghodrat Mahmoudi. "SHAPE-MEMORY EFFECT IN A FLEXIBLE POLYDENTATE PYRIDINE CONTAIN METAL−ORGANIC FRAMEWORK." PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 148, no. 02-02 (2024): 390–95. https://doi.org/10.36962/pahtei14802-022024-390.

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In the past few decades, due to human activities such as fossil fuel power generation, more and more CO2 in the atmosphere has been caused, and the greenhouse effect has become more and more obvious. This poses a huge threat to human and global security. At present, the CO2 concentration in the atmosphere has exceeded 400 ppm, which is about 40% higher than before industrialization, and the surface temperature has increased by about 0.8 °C [1]. In work, we illustrate deliberate design strategy based on a switchable porous new systems as member of a representative class of flexible MOFs via com

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Cox, Robin A., Ewart Grant, Todd Whitaker, and Thomas T. Tidwell. "The hydration of 1-aryl-3,3,3-trifluoropropynes and some other phenylacetylenes in sulfuric acid. An excess acidity analysis." Canadian Journal of Chemistry 68, no. 10 (1990): 1876–81. http://dx.doi.org/10.1139/v90-290.

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The excess acidity method has been used to analyse the hydration kinetics of the phenylacetylenes Y-C6H4-C≡C-Z in aqueous sulfuric acid mixtures; Z = CF3 (1), H (2), COC6H4-X (3), and CO2H (4). All substrates gave acetophenone-type products consistent with the normal hydration mechanism involving rate-determining vinyl cation formation. Standard-state log k0 intercepts, and m≠m* slopes, were both used in linear free energy relationship plots against the substituent σ+ values. Solvent isotope effects and activation parameters were obtained in some cases. The deactivating Z substituents in 1, 3,

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Kumar, Vivek, Abhay Kumar, and Rajesh Kumar. "Lemon Juice Catalysed Green Synthesis of Triazole Based Schiff Base, Its Physico-Chemical & Spectral Characterisation and Determination of its Binding Stoichiometry with Cu2+ ion." International Journal for Research in Applied Science and Engineering Technology 10, no. 2 (2022): 758–62. http://dx.doi.org/10.22214/ijraset.2022.40379.

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Abstract: In the recent years Environmental Pollution has emerged as a major challenge for human society. Since the start of Industrial Revolution in England, the amount of chemical waste and toxic substances are increasing exponentially in the environment. The traditional synthesis of chemical substances is accompanied by use of large amount of energy, harmful solvents and release of toxic substances in environment. The green synthesis aims to minimise the release and use of harmful toxic material in synthesis. In the present paper we have prepared a triazole derivative, 4-[(E)-Benzylideneami

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Schaefer, Ted, Christian Beaulieu, Rudy Sebastian, and Glenn H. Penner. "Experimental and theoretical estimates of the internal rotational barrier of benzyl fluoride in the vapor phase." Canadian Journal of Chemistry 68, no. 4 (1990): 581–86. http://dx.doi.org/10.1139/v90-089.

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The twofold barrier to rotation about the [Formula: see text] bond in benzyl fluoride is deduced from the long-range 1H,1H; 1H,19F; and 13C,19F nuclear spin–spin coupling constants in solution. The barrier changes from 3.2(2) kJ/mol in the polar solvent, acetonitrile-d3, to 0.7(2) kJ/mol in the nonpolar environment provided by cyclohexane-d12. In all solutions the conformer of greatest stability has the C—F bond in a plane perpendicular to that of the phenyl group. Extrapolation of the barrier to the vapor phase, using a simple reaction field model, indicates that the most stable conformer for

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Theresih, Karim, and Cornelia Budimarwanti. "PENGARUH GUGUS p-METOKSI PADA REAKSI KONDENSASI CLAYSEN-SCHMIDT MENGGUNAKAN METODA GRINDING." Jurnal Sains Dasar 5, no. 2 (2016): 124. http://dx.doi.org/10.21831/jsd.v5i2.13719.

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Penelitian ini bertujuan untuk mensintesis senyawa dibenzalaseton, 4-metoksikalkon dan dianizalaseton melalui reaksi kondensasi Claysen Schmidt menggunakan metode grinding dan mengetahui pengaruh gugus p-metoksi pada reaksi tersebut. Sintesis dibenzalaseton menggunakan benzaldehida, aseton, dan NaOH. Senyawa 4-metoksikhalkon disintesis dari campuran 4-metoksibenzaldehida, asetofenon, dan NaOH. Sedangkan sintesis senyawa dianisalseton melalui reaksi Claysen-schmidt antara aseton, anisaldehid, dan katalis basa NaOH dengan perbandingan mol yang digunakan secara berturut-turut 2:1:2. Sintesis dila

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Indrasti, Dias, and Siti Hanifah Rifan Ramadhina. "Volatile profile and its application on species authentication of meat-based food." Journal of Halal Science and Research 6, no. 1 (2025): 12–26. https://doi.org/10.12928/jhsr.v6i1.9798.

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Meat and meat-based food produces a certain composition of volatile compounds, which can be used to identify its origin and, consequently, for food authentication. Numerous studies have explored the application of volatile compounds in identifying meat-based food using volatilomics, an emerging analytical technique. This review focuses on the volatile compound profiles, the factors influencing their production, method of extraction and detection, and their application in meat and meat-based products, with a brief discussion on their potential use for Halal authentication. The major volatile co

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Choudhary, Alka N., Arun Kumar, Neetu Sharma, and Kapil Ghai. "Eco-friendly synthesis, biological evaluation and QSAR studies of dihydropyrimidinone/thione derivatives." Journal of medical pharmaceutical and allied sciences 11, no. 2 (2022): 4614–21. http://dx.doi.org/10.55522/jmpas.v11i2.2078.

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Dihydropyrimidinone/thiones (DHPMs) hold earmarked place in the field of natural and synthetic organic chemistry, because of their therapeutic and pharmacological properties. Synthesis of such biologically important compounds assumes great concern. Objectives The aim of the present work was to synthesize structurally challenging DHPMs through green procedure, evaluated for antibacterial activity and to perform QSAR analysis to attain the structural requirements for the antibacterial activity. The synthesis of dihydropyrimidinone/thiones was accomplished via three-component one-pot cyclocondens

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Nigussie, Gashaw, Abolghasem Siyadatpanah, Roghayeh Norouzi, Eyob Debebe, Mekdelawit Alemayehu, and Aman Dekebo. "Antioxidant Potential of Ethiopian Medicinal Plants and Their Phytochemicals: A Review of Pharmacological Evaluation." Evidence-Based Complementary and Alternative Medicine 2023 (October 12, 2023): 1–17. http://dx.doi.org/10.1155/2023/1901529.

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Background. Free radicals are very reactive molecules produced during oxidation events that in turn initiate a chain reaction resulting in cellular damage. Many degenerative diseases in humans, including cancer and central nervous system damage, are caused by free radicals. Scientific evidence indicates that active compounds from natural products can protect cells from free radical damage. As a result, the aim of this review is to provide evidence of the use of diverse Ethiopian medicinal plants with antioxidant properties that have been scientifically validated in order to draw attention and

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Santoso, Shella Permatasari, Niko Sanjaya, and Aning Ayucitra. "Pemanfaatan kulit singkong sebagai bahan baku pembuatan Natrium Karbosimetil Selulosa." Jurnal Teknik Kimia Indonesia 11, no. 3 (2018): 124. http://dx.doi.org/10.5614/jtki.2012.11.3.1.

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The use of cassava peels as raw material for Sodium Carboxymethyl Cellulose productionCassava peels are abundantly available and may be used as an lowcost cellulose source (80-85% cellulose per weight cassava peel). the study was to evaluate the effect of the concentration of sodium hydroxide, sodium chloroacetate, and temperature reaction on the sodium carboxymethyl cellulose (sodium-CMC) characteristics i.e. yield, purity, and degree of substitution in sodium-CMC preparation. Sodium-CMC functional group was determined using FTIR spectrophotometer. Cassava peels was dried and grounded to 50 m

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Kamanna, Kantharaju, and Yamanappagouda Amaregouda. "Synthesis of bioactive scaffolds catalyzed by agro-waste-based solvent medium." Physical Sciences Reviews, February 2, 2022. http://dx.doi.org/10.1515/psr-2021-0097.

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Abstract The backbone of synthetic organic chemistry is the formation of carbon–carbon and carbon–heteroatom bonds. Scientists are actively working to develop new methods of bond-forming reactions because it is one of the most useful tools for the development of structurally diverse molecular entities. On the other hand, scientists are constantly discovering chemical processes to make them more sustainable in order to avoid the ever-increasing chemical emission associated with hazards to the environment. Thus, the development of greener catalytic reactions demonstrated a massive uptick in the

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Sharma, Vishal, Monika Saini, Rina Das, et al. "Recent Updates on Antibacterial Quinolones: Green Synthesis, Mode of Interaction and Structure–Activity Relationship." Chemistry & Biodiversity, January 5, 2025. https://doi.org/10.1002/cbdv.202401936.

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ABSTRACTQuinolone antibiotics are a crucial class of synthetic antibacterial agents, widely utilized due to their broad spectrum of antibacterial activity. Due to the development of antimicrobial resistance, the potency of quinolone drugs decreased. Many conventional methods have been developed to elevate amination rate and to improve yield. These methods are generally characterized by prolonged reaction durations, high boiling solvents, harsh conditions, costly reagents and excessive heat generation, which have adversely affected the therapeutic efficacy of these compounds. Recently, green ch

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Devi Sri, Chiriki, Narasimha Murthy Beeraka, Hemanth Vikram P R, et al. "Updates on Intrinsic Medicinal Chemistry of 1,4-dihydropyridines, Perspectives on Synthesis and Pharmacokinetics of Novel 1,4-dihydropyrimidines as Calcium Channel Blockers: Clinical Pharmacology." Current Topics in Medicinal Chemistry 25 (January 1, 2025). https://doi.org/10.2174/0115680266323908241114064318.

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Background: Several chemical studies described the physiological efficacy of 1,4- dihydropyridines (DHPs). DHPs bind to specific sites on the α1 subunit of L-type calcium channels, where they demonstrate a more pronounced inhibition of Ca2+ influx in vascular smooth muscle compared to myocardial tissue. This selective inhibition is the basis for their preferential vasodilatory action on peripheral and coronary arteries, a characteristic that underlies their therapeutic utility in managing hypertension and angina. Among the vascular-selective DHPs, nifedipine, felodipine, and isradipine are key

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Rizana Azees, Asitha T. Cooray, and K.G.U.R. Kumarasinghe. "Microwave-assisted one-pot multicomponent synthesis of indole derived fluorometric probe for detection of Co2+ ions." Vidyodaya Journal of Science 24, no. 02 (2021). http://dx.doi.org/10.31357/vjs.v24i02.5413.

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Cobalt (Co2+) is an essential constituent in the human body while excessive exposure leads to severe systemic toxic reactions which highlight the importance of developing effective methods to detect Co2+ ions. A simple and highly efficient fluorescence enhanced turn OFF-ON chemosensor was synthesized to detect the paramagnetic Co2+. The ligand, N-((1H-indol-3-yl)(phenyl)methyl)aniline (L), was synthesized in 92% yield by means of hydrated ferric chloride catalyzed one -pot multicomponent microwave irradiation in the presence of Indole, benzaldehyde, and aniline as reactants. The major green pr

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Perera S.A.L., Palliyaguru L., and Jayaweera P.M. "Solvent-Free Green Synthesis of Cu0.5Ti2(PO4)3 and Cu0.5TiO(PO4) NASICON-Type Compounds from Ilmenite Mineral Sand." Proceedings of International Forestry and Environment Symposium 26 (June 7, 2022). http://dx.doi.org/10.31357/fesympo.v26.5759.

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Ilmenite is a naturally available black or steel-gray color mineral, called titanium iron oxide, FeTiO3.This valuable mineral comprises a significant amount of titanium that can be utilized as a titanium source to synthesize various materials. This study focused on synthesizing copper titanium phosphate compounds via an eco-friendly solid-state reaction route. α-titanium bismonohydrogen orthophosphate monohydrate (α-Ti(HPO4)2.H2O/α-TiP), derived from beach sand ilmenite used as the starting material for the synthesis. α-TiP was obtained by digesting ilmenite with 85 wt% phosphoric acid under r

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Kumarasinghe K.G.U.R. and Samaradiwakara D.M.T.A. "On-water Catalyst-free Synthesis of 3-Alkenyl Oxindoles." Proceedings of International Forestry and Environment Symposium 27 (February 15, 2024). http://dx.doi.org/10.31357/fesympo.v27.7168.

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3-Alkenyl oxindoles are key structural motifs in organic chemistry with a wide range of applications mainly in the pharmaceutical industry, due to excellent biological activities such as anti-inflammatory, antiviral, antibacterial, and anticancer properties. With the discovery of the importance of oxindole derivatives in the pharmaceutical industry, demand for sustainable protocols for the synthesis increased as most classical methods have their limitations and flaws. In this study on-water, catalyst-free, atom-economical green approach was developed for the synthesis of 3- alkenyl oxindole de

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Rasyid, Abdullah. "IDENTIFICATION OF SECONDARY METABOLITES COMPOUNDS, ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES ON THE METHANOL EXTRACT OF SEA CUCUMBER Stichopus hermanii." Jurnal Ilmu dan Teknologi Kelautan Tropis 4, no. 2 (2012). http://dx.doi.org/10.29244/jitkt.v4i2.7799.

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Identification of secondary metabolites, antibacterial and antioxidant activities assay of methanol extract of sea cucumber Stichopus hermanii were conducted from May to July 2011 at the Natural Products Laboratory, Research Center for Oceanography, Indonesian Institute of Sciences. Sea cucumber used in this study comes from South Lampung waters. Objective of the study was to get information of secondary metabolites, antibacterial and antioxidant activities of methanol extract of sea cucumber S. hermanii. The extraction method which used in this experiment was the maceration method using metha

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K.G.U.R. Kumarasinghe, H.H.Kandambi, and D.M.T.A.Samaradiwakara. "Recent Advances in Green Approaches for Synthesis of Oxindole Derivatives." Vidyodaya Journal of Science 1, s1 (2023). http://dx.doi.org/10.31357/vjs.v1is1.6715.

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Oxindole derivatives are nitrogen-containing, five-membered heterocyclic molecules found in both natural and synthetic substances with diverse biological functions. Owing to their pharmaceutical and therapeutic characteristics, oxindoles have received remarkable attention, and various oxindole-containing substances can be synthesized using many different approaches. With the discovery of the importance of oxindole derivatives in medicinal chemistry, mainly in drug synthesis, the demand for finding sustainable protocols has increased, as most classical methods have their limitations and flaws.

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Rasyid, Abdullah. "IDENTIFICATION OF SECONDARY METABOLITES COMPOUNDS, ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES ON THE METHANOL EXTRACT OF SEA CUCUMBER Stichopus hermanii." Jurnal Ilmu dan Teknologi Kelautan Tropis 4, no. 2 (2012). http://dx.doi.org/10.28930/jitkt.v4i2.7799.

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<p><strong>Identification of </strong>secondary metabolites, antibacterial and antioxidant activities assay of methanol extract of sea cucumber <span style="text-decoration: underline;">Stichopus</span> <span style="text-decoration: underline;">hermanii</span> were conducted from May to July 2011 at the Natural Products Laboratory, Research Center for Oceanography, Indonesian Institute of Sciences. Sea cucumber used in this study comes from South Lampung waters. Objective of the study was to get information of secondary metabolites, antibacterial and a

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Thu, Dang Kim, Hoang Thu Thuy, Bui Thi Thanh Duyen, et al. "Evaluating the Acetylcholinesterase Inhibitory and Antioxidant Activities of Persea Americana Extracts." VNU Journal of Science: Medical and Pharmaceutical Sciences 35, no. 1 (2019). http://dx.doi.org/10.25073/2588-1132/vnumps.4169.

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Medicinal plants are a potential source of enzyme acetylcholinesrerase (AChE) inhibitors, a key target in the treatment of Alzheimer’s disease. This paper studies the AChE inhibitory activity and the antioxidant effect of Persea Americana Mill extract. The sample leave, seed, exocarp and mesocarp of avocado were extracted with 50% ethanol and subsequently fractionated with n-hexane, ethyl acetate (EtOA) and n-butanol (n-BuOH) solvents. The AChE inhibitory activity was evaluated by Ellman’s colorimetric method and the antioxidant activity by screening DPPH free radicals. The results show that t

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Hussain, Zahid. "Advances in Enzyme Engineering for Biofuel Production: Strategies and Challenges." March 1, 2025. https://doi.org/10.5281/zenodo.14949583.

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<strong>Advances in Enzyme Engineering for Biofuel Production: Strategies and Challenges</strong> <strong> </strong> <strong>Abstract</strong> The increasing global demand for sustainable and renewable energy sources has driven significant advancements in enzyme engineering for biofuel production. Enzymes such as cellulases, xylanases, and lipases play a pivotal role in breaking down lignocellulosic biomass and converting lipids into biofuels. This review explores recent <strong>strategies in enzyme engineering</strong>, including <strong>rational design, directed evolution, and protein e

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