10.1039/c8nj00075a
The study focuses on the development of an efficient copper-mediated coupling method for the synthesis of diaryl sulfones from arylsulfonyl hydrazides and aryl iodides or bromides using cupric acetate as a catalyst and polyethylene glycol (PEG-400) as an eco-friendly solvent. The study explores the optimal reaction conditions, including the influence of different PEG chain lengths, various copper sources, and the necessity of an external base. The reaction's scope was investigated with a range of substituted aryl iodides and arylsulfonyl hydrazides, demonstrating good functional group tolerance and moderate to good yields. The experiments utilized techniques such as GC-MS analysis to detect products and radical inhibitors to probe the reaction mechanism, suggesting a plausible pathway involving the formation of a copper-arylsulfonyl intermediate.
10.1080/00397911.2010.551700
The research focuses on the development of an efficient, green, and one-pot synthesis method for bis-indolyl and tris-indolyl methanes using poly(ethylene glycol)-bound sulfonic acid (PEG-SO3H) as a catalyst in aqueous media. The study explores the condensation of indole with a variety of structurally diverse aldehydes and ketones at room temperature, aiming to produce biologically active compounds with potential therapeutic importance. The experiments involved the use of PEG-SO3H as a catalyst, with reactions carried out in water, leading to good to excellent yields in shorter reaction times. The analyses used to characterize the synthesized compounds included melting point determination, infrared (IR) spectroscopy, liquid chromatography-mass spectrometry (LCMS), and nuclear magnetic resonance (NMR) spectroscopy, providing comprehensive data on the structure and purity of the products.
10.1016/j.tet.2012.05.112
The research focuses on the efficient and straightforward synthesis of functionalized furo[3,2-c]coumarins through a one-pot oxidative pseudo three-component condensation reaction. The reactants involved in this green chemistry approach include aldehydes, 4-hydroxycoumarin, and a mixture of I2 and K2S2O8 in the presence of Na2CO3, which serves as an oxidative reagent. The synthesis takes place in poly(ethylene glycol) (PEG), a non-toxic, recoverable solvent. The synthesized furo[3,2-c]coumarins were characterized using various analytical techniques, including X-ray single crystal structure analysis, IR and 1H-13C NMR spectroscopy, mass spectrometry, and elemental analysis, which confirmed the structure and purity of the compounds. The study also optimized reaction conditions to achieve good yields and explored the reusability of the oxidant and solvent, demonstrating their effectiveness over multiple cycles.
10.1016/j.ica.2011.06.036
The study focuses on the synthesis and characterization of photofunctional Eu3+/Tb3+ hybrid materials, which are inorganic silica covalently linked to organic polymer chains through sulfide bridges. The main chemicals used include 2-thiosalicylic acid (TSA), crosslinking reagents 3-chloropropyltrimethoxysilane (CTPMS) and 3-(triethoxysilyl)-propyl isocyanate (TESPIC), tetraethoxysilane (TEOS), europium and terbium nitrates, and organic polymers polyacrylamide (PAM) and polyethylene glycol (PEG). These chemicals serve to create sulfide-bridged molecular linkages and polymeric silane derivatives, which are then assembled into multi-component hybrid materials through co-hydrolysis and co-polycondensation with TEOS. The purpose of these materials is to improve photoluminescence properties by integrating the benefits of both inorganic silica and organic polymers, such as enhanced thermal or optical stabilities, chemical stability, and mechanical strength. The study aims to develop hybrid systems with improved luminescence behavior for potential applications in luminescence and laser fields.
10.1016/j.tetasy.2008.03.015
The research focuses on developing a new polyethylene glycol (PEG) supported ruthenium (Ru) catalyst for the asymmetric transfer hydrogenation of various aromatic ketones in water. The purpose of this study is to improve the solubility and reactivity of the catalyst in water, an environmentally friendly solvent, while maintaining high enantioselectivity and chemical yields without the need for surfactants. The key chemicals used include the PEG-supported ligand (PEG-BsDPEN), [RuCl2(p-cymene)]2 as the Ru precursor, sodium formate (HCOONa) as the hydrogen donor, and various aromatic ketones as substrates. The study concludes that the new PEG-BsDPEN catalyst achieves high enantioselectivities (up to 99% ee) and good chemical yields in water. Additionally, the catalyst can be easily recovered and reused multiple times with minimal loss of activity and enantioselectivity, demonstrating its practicality and sustainability for asymmetric transfer hydrogenation reactions.
10.1002/aoc.3815
This study focuses on the synthesis, characterization, and application of nano-CoAl2O4 as an efficient catalyst in the preparation of hexahydroquinolines. The researchers prepared nano-CoAl2O4 using a solution of metal sulfates, polyethylene glycol, and sodium hydroxide, and then calcined it at 800°C for 6 hours. The catalyst was characterized by various techniques including FT-IR, EDX, XRD, SEM, VSM, and TEM. In the synthesis of hexahydroquinolines, nano-CoAl2O4 was used to catalyze the condensation reaction between ethyl acetoacetate, dimedone, and various aldehydes under solvent-free conditions at 80°C. The study demonstrated that the use of nano-CoAl2O4 as a catalyst resulted in high yields, short reaction times, and the ability to reuse the catalyst multiple times without significant loss of efficiency.
10.1071/CH08041
The research focuses on the uncatalyzed synthesis of β-enamino ketones, which are valuable precursors for the synthesis of heterocyclic compounds and biologically active molecules. The purpose of the study was to develop an eco-friendly and efficient method for synthesizing these compounds using polyethylene glycol (PEG)-600 and water as a solvent system, which is a non-hazardous alternative to traditional organic solvents. The researchers successfully synthesized β-enamino ketones by reacting aromatic or aliphatic amines with 1,3-dicarbonyl compounds in PEG-600–water, achieving excellent yields without the need for catalysts or azeotropic removal of water. The process was optimized at 100°C, and PEG-600 was found to be recyclable and reusable, maintaining high yields even after multiple uses. The study concluded that an environmentally benign method for the synthesis of β-enamino ketones under neutral conditions had been developed, showcasing the potential of PEG-600 as a sustainable solvent in organic synthesis.
10.1021/jo00314a054
The research involves the synthesis of various organic compounds, primarily focusing on the introduction of fluorine into biologically active molecules to induce new pharmacological properties. Key chemicals involved include fluoroveratroles, fluorophenethylamines, and difluorophenethylamine. The synthesis processes involve multiple steps, utilizing reagents such as lithium bromide, m-chloroperbenzoic acid, potassium tert-butoxide, and PEG 1000. The study also explores the preparation of fluoromethyl ketones through the exchange of bromine by fluorine in bromomethyl ketones, using potassium fluoride and 18-crown-6 ether or PEG 1000 as the fluoride ion source. The synthesized compounds are characterized by NMR, mass spectrometry, and elemental analysis, confirming their structures and purity.
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