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Methods involving C–C bond formation are continuously being innovated due to their importance in the creation and modification of important organic molecules. The classic Grignard reaction demonstr...

Improved methods for the synthesis of KB3H8, NH3B3H7, and N-alkyl analogues of NH3B3H7 have been developed based on previous works. KB3H8 was synthesized by the reaction of metallic potassium (K) with borane dimethyl sulfide ((CH3)2S·BH3) with high yield and atom-economy. In the preparation of NH3B3H7 and its N-alkyl analogues, KB3H8 served as a starting material and was converted to THF·B3H7 first through reactions with HCl diethyl ether solution or oxidation agent CoCl2. Then, the formed THF·B3H7 in situ reacted with the corresponding ammonia or amines to form the amine borane final products. This work paves an alternative way for preparing organic-inorganic hybrid materials containing B, N, and C atoms.

The knowledge of green chemistry is instrumental in reducing the harmful and toxicity of the environment. The current environment demands that conventionally used petrochemical solvents should be replaced with the recently developed less harmful and less toxic green solvents. The potential applications of green chemical as solvents are required to study based on the green chemistry principles and the separation of solvents. In this review paper, the application of green chemicals was described for five green solvents such as cyclopentyl methyl ether (CPME), 2-methyl tetrahydrofuran (2-MeTHF), propylene carbonate, 1,3-propanediol, and ethyl lactate. The replacement study of conventional petrochemical solvents with these green solvents was discussed here. Based on the comparative studies, the green chemicals were found to be high potential solvents to replaced tetrahydrofuran (THF), dichloromethane (DCM), 1,4-dioxane, and diethyl ether in chemical industry.

The reaction of dialane [LAl-AlL] (1; L=dianion of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene, dpp-bian) with carbon dioxide results in two different products depending on solvent. In toluene at temperatures of about 0 °C, the reaction gives cycloadduct [L(CO2 )Al-Al(O2 C)L] (2), whereas in diethyl ether, the reaction affords oxo-bridged carbamato derivative [L(CO2 )(Et2 O)Al(μ-O)AlL] (3). The DFT and QTAIM calculations provide reasonable explanations for the reversible formation of complex 2 in the course of two subsequent (2+4) cycloaddition reactions. Consecutive transition states with low activation barriers were revealed. Also, the DFT study demonstrated a crucial effect of diethyl ether coordination to aluminium on the reaction of dialane 1 with CO2 . The optimized structures of key intermediates were obtained for the reactions in the presence of Et2 O; calculated thermodynamic parameters unambiguously testify the irreversible formation of the product 3.

Addition of 2-adamantylMgBr in diethyl ether to Mo(NArF)2(Cl)2(DME) (ArF = C6F5) gave Mo(NArF)2(Ad)2 (2, Ad = 2-adamantyl, DME = 1,2-dimethoxyethane). Addition of HCl and 2,2′-bipyridyl (bipy) to 2...

A one-pot three-component reaction of several 2-ketoaldehydes, secondary amines and terminal alkynes to access 3-aminofurans proceeded well in [bmim][PF6] using a simple and cheap CuI catalyst. The resultant 3-aminofuran products were easily isolated using diethyl ether and the CuI/[bmim][PF6] system was reused six times with a slight decrease in the activity.

Previous studies on fast living cationic polymerisation have rarely focused on the effects of nucleophiles, which are crucial in determining a suitable initiation system. In this work, taking the polymerisation of isobutyl vinyl ether (IBVE) as an example, the effects of various nucleophiles, namely ethyl acetate, 1,4-dioxane, 1,3-dioxolane, diethyl ether, and ethyl propionate, on the activity and stability of the propagating chains were systematically examined in a microflow system, in which IBVE-HCl/SnCl4 was selected as the initiation system and 2-hydroxyethyl methacrylate was employed as an effective end-capping agent for 1H NMR spectroscopy measurements. The characteristic time of activity (tact) and the half-life of stability (tdecay) exhibited almost linear proportional relationships, revealing that the nucleophiles did not alter the relative values of activity and stability, acting simply to improve the controllability of the cationic polymerisation process. Furthermore, a density functional theory simulation method was established to calculate the dissociation energy of IBVE/SnCl4/Nus (ΔE). Approximately linear relationships between ln(tact) or ln(tdecay) and ΔE were found, indicating the potential of theoretical calculations to estimate the activities and stabilities of the propagating chains in this process.

A study is performed of the processes of low-temperature enzymatic synthesis of esters in nonaqueous media of organic solvents with the participation of heterogeneous biocatalysts produced by the adsorptive immobilization of recombinant Thermomyces lanuginosus lipase (produced by Pichia pastoris) on macroporous carbon aerogel. Esterification is conducted in individual organic solvents of different polarities, namely nonpolar (lоg P > 2.5) solvents hexadecane, hexane, and toluene; the polar (lоg P < 1) diethyl ether, tert-butanol, and acetone; binary mixtures with different compositions (e.g., hexane with diethyl ether in volume ratio 1 : (1/5–3)). Comparative studies are made of the effect the nature of the solvent and co-solvent on the properties of the prepared biocatalysts (such as enzymatic activity and operational stability) in the batch esterification of heptanoic acid (C7:0) with alcohols such as polar ethanol and n‑butanol, and nonpolar n-octanol and n-hexadecanol. The activity of the biocatalysts is found to depend largely on the polarity of both the solvents used in the reaction and the alcohol substrates. The maximum activity (400 U g−1; 1 U (unit of activity) = 1 μmol min−1) is observed in a medium of nonpolar and inviscid hexane (lоg P = 2.9), while the minimum activity (4 U g−1) is detected in acetone (lоg P = 0.4). There is virtually no esterification of heptanoic acid in the presence of tert-butanol (lоg P = 0.6). The activity of the biocatalysts is found to depend nonmonotonically on the lоg P of individual solvent. In binary mixtures of such organic solvents as hexane and diethyl ether, the biocatalytic activity increases linearly as lоg Pmix increases. The biocatalysts have the maximum operational stability in binary mixture of hexane and diethyl ether.

Poly(e-caprolactone) (PCL) is a widely employed biodegradable polymer synthesized commercially using stannous octoate-mediated ring-opening polymerization (ROP) of e-caprolactone (e-CL). It needs to be revisited in alignment with green chemistry principles, such as less hazardous chemical syntheses. We identified and optimized two emerging methods—Route A: acid-catalyzed ROP of e-CL using hydrogen chloride (HCl) in diethyl ether; and Route B: free-radical ROP using cyclic ketene acetal (CKA) monomer, 2-methylene-1,3-dioxepane (MDO), which are essentially solvent-free, metal-free, and organic-catalyst-free. They were then compared with the laboratory-scale reproduction of Route C: stannous octoate-mediated ROP of e-CL. Laboratory-scale life-cycle assessment (LCA) is employed to analyze the potential environmental profiles of these three routes by employing a cradle-to-gate system boundary, starting from extraction of raw materials and ending with production of 1 g of PCL homopolymer. The overall findings showed that Route A, the low-temperature acid-catalyzed approach, was more power-efficient and less hazardous compared to Routes B and C, with consideration of sensitivity and uncertainty analysis results. Route A was demonstrated to be the most environmentally sustainable route with environmental impact reductions of 79.46% (climate change), 54.53% (fossil fuel depletion), 45.10% (terrestrial acidification), and 66.36% (water depletion) per 1 g of PCL, in contrast to Route B. In comparison to Route C, Route A achieved 43.54% (fine particulate matter formation) and 98.41% (human toxicity) impact reductions per 1 g of PCL. Route B contributes largely to climate change, whereas Route C has the most significant influence on human toxicity.

Lipophilic constituents of sea buckthorn leafy shoots, which is a large-scale waste product of sea buckthorn oil production and rejuvenating pruning of cultivated sea buckthorn plants, is investigated. Methyl tert-butyl ether (MTBE) is used as an extraction solvent. It features all the advantages of diethyl ether while lacking its disadvantages: it is not prone to peroxide formation and is not a significant air pollutant due to its higher boiling point. The chemical composition of MTBE extract of sea buckthorn leafy shoots is studied by gas chromatography mass spectrometry and high-performance liquid chromatography. Seventy-four neutral and 38 acidic components, including polyprenols, dolichols, triterpene alcohols and acids, and sterols are identified. In comparison to hexane, MTBE, as an extraction solvent, provides higher yields of bioactive triterpene acids and diols, including uvaol, eritrodiol, and betulin. The presence of these compounds in the prepared extract may enhance its beneficial properties.

In this research, a one-pot production of biodiesel, hydrocarbons, oxygenates, and aromatics form Chlorella vulgaris was performed in supercritical methanol without catalyst and in the presence of TiO2 and SrTiO3 nanocatalysts. The reaction in the presence of SrTiO3 showed the highest production yield of fatty acid methyl esters (FAMEs). The co-solvents water, chloroform, diethyl ether, and n-hexane were used for modifying the supercritical medium to affect the product yields in SrTiO3-catalyzed process. The SrTiO3 nanocatalyst was photochemically prepared and the leaching of catalysts into the products was evaluated. Results showed that for all products except oxygenates, the addition of diethyl ether and chloroform to methanol had a slightly positive effect on the production yields. For all products, n-hexane co-solvent showed the best performance with production yields of 16.65, 2.42, 2.12, and 0.57 mg.g−1biomass for FAMEs, oxygenates, hydrocarbons, and aromatics, respectively. Furthermore, the water showed no significant effect on production yields except in the case of oxygenates. The results may be due to the high ability of n-hexane for dissolving the biomass in the reaction condition. Also, the ICP-OES detected no trace amounts of catalyst in the final product and it confirms that the photochemical method for catalyst preparation can prevent the catalyst leaching.

The deprotonation of 3-aryl-substituted alkyl propargyl ethers with n-butyllithium provides an ambident anion that reacts with carbonyl compounds to provide mixtures of γ-substituted products with alkoxyallene substructure and of α-substituted propargyl ethers. The ratio of the two product types strongly depends on the solvent: in diethyl ether the γ-substituted products predominate whereas the more polar tetrahydrofuran favors the α-adducts. The primary addition products undergo 5-endo-trig or 5-endo-dig cyclizations under various reaction conditions to afford isomeric furan derivatives. The highest selectivity in favor of α-substituted products was achieved by employing a MOM-protected propargyl ether. During the protonation step no evidence for a proton shift leading to an isomeric allenyl anion was found. A brief mechanistic discussion tries to rationalize the observed regio­selectivities.

The reaction of hexaphenyl-carbodiphosphorane (1) with equi- or twice-molar amounts of PhLi or n-BuLi in diethyl ether is leading selectively to dilithio-carbodiphosphorane (3). Under optimized con...

Efficient and reliable synthesis of substituted hydrazinylpyridines in thick-wall ACE tubes via nucleophilic substitution of a chlorine substituent in different chloropyridines is presented. Hydrazine hydrate and alkylhydrazines were used as nucleophiles and simple alcohols and diethyl ether were the only organic solvents necessary, making the process environmentally and user friendly, potentially reaching 100% atomic efficiency. In the next step, transformations of succinic anhydride moieties fused to the bicyclo[2.2.2]octene framework into succinimide moieties via nucleophilic substitution of oxygens were conducted. As nucleophiles two of the synthesized hydrazinylpyridines (2-hydrazinyl-3-nitropyridine and 2-hydrazinyl-5-nitropyridine) and also hydrazine hydrate, phenylhydrazine, and 4-nitrophenylhydrazine were used. Reactions were again carried out in ACE tubes and only simple alcohols, diethyl ether, and acetone were needed as solvents. One of the prepared bicyclo[2.2.2]octene adducts displayed water solubility thus being a promising candidate for future studies as a novel bidentate ligand for various metal cations in aqueous solutions or acting as an unprecedented halogen bond acceptor.

In this investigation, chromatographic separations of the diethyl ether extracts of two European annual Bupleurum taxa, B. praealtum and B. veronense, yielded nine new natural products, namely, a series of esters of stereoisomeric tetradeca-5,7,9,11-tetraen-1-ols (1-4 and 8), a tetra-unsaturated γ-tetradecalactone (5), a dibenzylbutyrolactone lignan (7-oxoarcitin, 6), a falcarinol-related 17-membered macrolide (7) possessing a conjugated diyne-system, and an acylphloroglucinol derivative (9). All these new compounds were fully characterized by NMR, IR, UV, MS, and optical rotation measurement, including 1H NMR full spin spectral simulation, whereas the absolute configurations of 1, 5, and 9 were determined via chemical correlations and NMR analysis of Mosher esters. The in vitro potential immunomodulatory activities of 1, 4, 5, and (+)-arcitin were assessed by determining their effects on the functional properties of isolated rat splenocytes and peritoneal macrophages. The results obtained support the known immunomodulatory ethnomedicinal usage of Bupleurum species.

The paper is devoted to the development of diethyl ether + hexane + ethyl acetate + ethanol mixture (solvents of the dihydroquercetine production) separation flowsheets based on the analysis of the structure of the phase diagram. The phase equilibrium of the quaternary system was studied using mathematical modeling in the AspenPlus. The parameters of Non Random Two Liquid model allow reproducing vapor-liquid equilibrium data and azeotropes characteristics with a relative error not exceeding 5%. It was shown that the system was characterized by the presence of three binary azeotropes and the phase diagram was divided into three distillation regions. Based on a literature analysis N-methyl-2-pyrrolidone was selected as a solvent for the extractive distillation. The selectivity of the separating agent was calculated and it was shown that N-methyl-2-pyrrolidone influenced the relative volatility of components to varying degrees. Two flowsheets containing a diethyl ether separation column and two extractive distillation complexes were proposed. The flowsheets differ in the sequence of separation of the components: hexane, ethyl acetate and ethanol. The distillation process was simulated and the operating column parameters (number of stages, feed stage, reflux ratio, solvent to feed volume ratio) were determined. Selected parameters meet the minimum energy consumption. An energy-efficient separation variant was chosen.

Densities of pure liquids and binary mixtures of diethyl ether (DEE) with 2-alkoxyethanols (2- methoxyethanol, 2-ethoxyethanol and 2-butoxyethanol) have been determined over the entire range of solvent compositions at (293.15, 298.15 and 303.15) K. Excess molar volumes (VM E ) have been calculated from the density data and were fitted into the Redlich-Kister type polynomial equation to obtain the fitting parameters Ai. The values of excess molar volumes, vm E were negative in regions of low diethyl ether (DEE) composition and small positive values were observed in regions of high diethyl ether (DEE) compositions in all the systems studied. VM E values were also found to decrease with increase in temperature and increase in chain length of the 2-alkoxyethanols. The above trends were attributed to the combined effects of disruption and formation of hydrogen bonds between like molecules of 2- alkoxyethanols and unlike molecules of diethyl ether (DEE), respectively.

Processes of the low-temperature enzymatic synthesis of esters in nonaqueous media of organic solvents with participation of heterogeneous biocatalysts synthesized by the adsorption immobilization of a recombinant lipase from Thermomyces lanuginosus (Pichia pastoris producer) on macroporous carbon aerogel were investigated. The esterification reaction was conducted using individual organic solvents of different polarity, such as nonpolar ones (lоgP > 2.5) – hexadecane, hexane and toluene, and polar solvents (lоgP < 1) – diethyl ether, tert-butanol and acetone, as well as their binary mixtures of different composition, for example, a mixture of hexane with diethyl ether having the composition 1 : (1/5÷3, vol. fr.). The effect of the solvent and co-solvent nature on the properties of synthesized biocatalysts, namely the enzymatic activity and operational stability, was studied in the batch esterification of heptanoic acid (C7:0) by alcohols, particularly the polar substrates – ethanol and n-butanol, or nonpolar alcohols – n-octanol and n-hexadecanol. Activity of the synthesized biocatalysts was found to depend to a great extent on polarity of both the solvents used in the reaction and the alcohol substrates. The maximum activity of 400 EA·g–1 was observed in a medium of nonpolar and nonviscous hexane (lоgP = 2.9), whereas the minimum activity of 4 EA·g–1 – in acetone (lоgP = 0.4); esterification of heptanoic acid in the presence of tert-butanol (lоgP = 0.6) virtually did not proceed. The activity of biocatalysts was shown to depend nonmonotonically on the lоgP value of individual solvent. In the binary mixtures of organic solvents, such as hexane/diethyl ether, biocatalytic activity linearly increased with an increase in lоgPmixture; in addition, biocatalysts exhibited the maximum operational stability.

The solubility of benzanilide in sixteen pure organic solvents, including N, N-dimethylformamide, tetrahydrofuran, butanone, acetone, ethyl acetate, dichloromethane, n-butanol, diethyl ether, n-pro...

Addition of 2-adamantylMgBr in diethyl ether to Mo(NAr)2(Cl)2(DME) (Ar = 2,6-i-Pr2C6H3) gave Mo(NAr)2(2-Ad)2 (2-Ad = 2-adamantyl, DME = 1,2-dimethoxyethane), from which Mo(NAr)(Adene)(OTf)2(DME) (1...

Curcumin is a chemical compound with antioxidant properties as well as strong anti-inflammatory, antiviral, analgesic, antimicrobial and antitumor effect, contained in the tuberous rhizomes of the turmeric plant (Curcuma longa). Curcumin derivatives are being intensively studied as potential drugs – antitumor drugs for the treatment of certain forms of cancer. The presence of reactive functional groups makes curcumin a convenient starting compound for the further chemical modification. The esters of curcumin and 5-phenylisoxazole-3-carboxylic acid, 5-(p-tolyl)isoxazole-3-carboxylic acid, 4,5- dichloroisothiazole-3-carboxylic acid and adduct of 5-(p-tolyl)isoxazol-3-carbaldehyde with curcumin were synthesized. Esters were obtained by acylation of curcumin with heterocycle-containing carboxylic acid chloride in diethyl ether in the presence of triethylamine. The IR and NMR spectra of the obtained compounds are described.

This study reports a new series of 12 α-lithiated allylic phosphines and phosphine oxides. By incorporating Lewis base donors including diethyl ether (Et2O), tetrahydrofuran (THF), N,N,N′,N′,-tetra...

The solubility of dimethyl 2,2′-azobis(2-methylpropionate) (AIBME) was determined in 15 pure solvents, including cyclohexane, dichloromethane, diethyl ether, acetone, tetrahydrofuran, ethyl acetate...

A general preparation of enantiomerically and diastereomerically enriched secondary alkylmagnesium reagents was reported as well as their use for performing highly stereoselective transition-metal free electrophilic aminations leading to α-chiral amines in up to 97% ee. Thus, the reaction of t-BuLi (2.2 equiv.) with a mixture of chiral secondary alkyl iodides and the commercially available magnesium reagent Me3SiCH2MgCl in a 2 : 1 mixture of pentane and diethyl ether at up to −50 °C provided optically enriched secondary mixed alkylmagnesium species of the type alkyl(Me)CHMgCH2SiMe3 with high retention of configuration (up to 99% ee). The resulting enantiomerically enriched dialkylmagnesium reagents were trapped with electrophiles such as non-enolizable ketones, aldehydes, acid chlorides, isocyanates, chlorophosphines and O-benzoyl hydroxylamines providing α-chiral tertiary alcohols, ketones, amides, phosphines and tertiary amines in up to 89% yield (over three reaction steps) and up to 99% ee., We report a general method for the preparation of enantiomerically enriched secondary alkylmagnesium reagents, which undergo highly stereoselective transition-metal free electrophilic aminations, leading to α-chiral amines in up to 97% ee.

Numerous species of Allium genus have been used in the traditional medicine based on their vast biological effects, e.g., antimicrobial, digestion stimulant, anti-sclerotic, soothing, antiradical or wound healing properties. In this work, unpolar and polar extracts from two lesser-investigated species of Allium growing in Kazakhstan, Allium galanthum Kar. &amp, Kir. (AG) and A. turkestanicum Regel. (AT), were studied for their composition and biological effects. In the HPLC-ESI-QTOF-MS/MS analyses of water and alcoholic extracts simple organic acids, flavonoids and their glycosides were found to be the best represented group of secondary metabolites. On the other hand, in the GC-MS analysis diethyl ether, extracts were found to be rich sources of straight-chain hydrocarbons and their alcohols, fatty acids and sterols. The antimicrobial activity assessment showed a lower activity of polar extracts, however, the diethyl ether extract from AT bulbs and AG chives showed the strongest activity against Bacillus subtilis ATCC 6633, B. cereus ATCC 10876, some species of Staphylococcus (S. aureus ATCC 25923 and S. epidermidis ATCC 12228) and all tested Candida species (Candida albicans ATCC 2091, Candida albicans ATCC 10231, Candida glabrata ATCC 90030, Candida krusei ATCC 14243 and Candida parapsilosis ATCC 22019) with a minimum inhibitory concentration of 0.125–0.5 mg/mL. The highest antiradical capacity exhibited diethyl ether extracts from AG bulbs (IC50 = 19274.78 ± 92.11 mg Trolox eq/g of dried extract) in DPPH assay. In ABTS scavenging assay, the highest value of mg Trolox equivalents, 50.85 ± 2.90 was calculated for diethyl ether extract from AT bulbs. The same extract showed the highest inhibition of mushroom tyrosinase (82.65 ± 1.28% of enzyme activity), whereas AG bulb ether extract was the most efficient murine tyrosinase inhibitor (54% of the enzyme activity). The performed tests confirm possible cosmeceutical applications of these plants.

In the in situ Grignard metalation method (iGMM), the addition of bromoethane to a suspension of magnesium turnings and cyclopentadienes [C5H6 (HCp), C5H5‐Si(iPr)3 (HCpTIPS)] in diethyl ether smoothly yields heteroleptic [(Et2O)Mg(CpR)(μ‐Br)]2 (CpR=Cp (1), CpTIPS (2)). The Schlenk equilibrium of 2 in toluene leads to ligand exchange and formation of homoleptic [Mg(CpR)2] (3) and [(Et2O)MgBr(μ‐Br)]2 (4). Interfering solvation and aggregation as well as ligand redistribution equilibria hamper a quantitative elucidation of thermodynamic data for the Schlenk equilibrium of 2 in toluene. In ethereal solvents, mononuclear species [(Et2O)2Mg(CpTIPS)Br] (2’), [(Et2O)nMg(CpTIPS)2] (3’), and [(Et2O)2MgBr2] (4’) coexist. Larger coordination numbers can be realized with cyclic ethers like tetrahydropyran allowing crystallization of [(thp)4MgBr2] (5). The interpretation of the temperature‐dependency of the Schlenk equilibrium constant in diethyl ether gives a reaction enthalpy ΔH and reaction entropy ΔS of −11.5 kJ mol−1 and 60 J mol−1, respectively., Cyclopentadienylmagnesium bromides are accessible with high yields by a fast and smooth one‐pot synthesis. In hydrocarbons and in ethereal solvents a dissociative Schlenk equilibrium is operative interconverting heteroleptic compounds into homoleptic congeners.

4,4′-Di-tert-butyl-2,2′-bipyridinium trifluoromethanesulfonate was synthesized by stirring 4,4′-Di-tert-butyl-2,2′-bipyridine with scandium(III) trifluoromethanesulfonate in acetonitrile, followed by precipitation with diethyl ether. The structure of the new compound was characterized by FT-IR, 1H, 13C{1H} and 19F{1H} NMR spectroscopy and CHN elemental analysis. This is a safe and simple method to obtain mono-protonated bipyridinium trifluoromethanesulfonate without the direct use of trifluoromethanesulfonic acid.

Compounds with ordered structures in one or two dimensions are exciting materials and investigated intensively in many different areas of science. Many activities have been put into the preparation of low‐dimensional nano‐scaled structures and many compounds in this size regime are known. Contrary, the number of known compounds that have low‐dimensional macroscopic sized structures that form directly in a chemical reaction is very limited. Here, we present the synthesis of the niobium cluster compound [(Et2O)2H]2[Nb6Cl18], crystals of which grow in form of large hexagonal empty tubes of several centimeter length and diameters in the range of 2 mm. The single‐crystal X‐ray structure of this compound has been refined. Under warming, the compound readily eliminates diethyl ether molecules and decomposes. From a closer look at the crystallization process a step‐by‐step scheme of the procedure of the tube growth is proposed. The overall conclusion from this proposal is that a crucial balance between the cluster solution concentration, the crystal growth speed and the ether diffusion speed results in the formation of macroscopic crystal tubes., Growing tubes: Under appropriate conditions of ether vapor diffusion, the cluster compound [(Et2O)2H]2[Nb6Cl18] forms as macroscopic tubes with millimeter‐size inner diameters.

Three-component reaction between arylglyoxals, 1,3-dicetones and enaminoketones leads to new polyfunctionalized tetraone derivatives which may be easily converted to polyfunctionalized pyrroles. Reactions were conducted in water or water-ethanol mixture as green solvents, and all products were isolated by simple washing of the resulting solids with diethyl ether.

Immobilization of recombinant Thermomyces lanuginosus lipase (designated as rPichia/lip) was carried out by moisture capacity impregnation of mesoporous silica granules followed by drying, and forcible adsorption of enzyme occurred. Eventually prepared lipase-active heterogeneous biocatalysts were systematically studied for enzymatic esterification performed at ambient conditions (20 ± 2 °C, 1 bar) in unconventional anhydrous media of organic solvents such as hexane and diethyl ether. The saturated fatty acids differing in the number of carbon atoms (C2–C10, C18), and aliphatic alcohols differing in the structure of the molecules, namely both the number of carbon atoms (C2–12, C16), and the isomerism of the carbon skeleton (n- and iso-), and OH-group position (prim-, sec-, tert-) were studied as substrates for enzymatic esterification. The specificity of the heterogeneous enzymatic esterification was determined by comparing the reaction rates for various pairs of substrates; and the matrix of relative units of activities was composed. The immobilized on silica rPichia/lip was found to have sufficiently wide specificity toward saturated fatty acids and aliphatic alcohols. High reaction rates were measured in esterification of fatty acids and primary n- and iso-aliphatic alcohols possessing more than four carbon atoms in the molecules. The enanthic acid (heptanoic, C7:0) reacted with butanol (C4) with the highest rate; and the kinetic parameters such as Michaelis constant (KM) for acid and maximal reaction rate (Vmax) were determined under the studied conditions of esterification. Substrates containing aromatic residues did not participate in esterification. The lipase-active heterogeneous biocatalysts possessed considerably high operational stability, and the catalytic activity was completely retained for several tens of reaction cycles in a periodic batch process of low-temperature synthesis of various fatty acid esters.

The aim of this study is to define chemical composition and antiproliferative activity of several compounds isolated from Schinus molle male and female flowers on human neuroblastoma (SH-SY5Y) and human leukemia (HL60) cell lines. Three extracts obtained by using solvents with different polarities (petroleum ether, diethyl ether and acetone) were characterized by GC/MS analysis revealing qualitative and quantitative differences in the chemical composition of male and female flowers. Nineteen components were identified and both flower extracts were dominated by the sesquiterpene hydrocarbons fraction, mainly elemol, followed by bicyclic sesquiterpenes and by a smaller amount of monoterpenes. The biological activities of the extracts were evaluated by dose-dependent viability assay on two different cell lines and HL60 cells resulted more sensitive to the treatment. The presence of compounds at low concentration with a well-established cytotoxic activity such as β-elemene, β-caryophyllene and γ-eudesmol could exert a synergistic cytotoxic effect.

The reaction of hydroxybenzoyl chlorides with imidazole was studied on an example of the Schotten-Baumann reaction of salicyloyl and acetylsalicyloyl chlorides with imidazole, which, according to soe published data, can take two different ways. It was shown that the Schotten-Baumann reaction with imidazole involves imidazole ring opening (Bamberger cleavage) to form l,2-bis(salicyloylamino)ethylene and l,2-bis(acetylsalicyloylamino)ethylene rather than N-salicyloylimidazole and N-acetylsalicyloylimidazole. N-Hydroxybenzoylimidazoles were synthesized by the reaction of hydroxybenzoyl chlorides (and derivatives) with a double excess of imidazole in an aprotic solvent (chloroform, benzene, or diethyl ether) at room temperature. The highest yields (about 80%) of N-hydroxybenzoylimidazoles were obtained in chloroform. Some of the newly synthesized compounds were tested for psychotropic (open field and passive avoidance response tests) and analgesic activities (vocalization threshold test). The best results were obtained with N-(2-hydroxybenzoyl)imidazole, which showed an evident analgesic activity, and, therewith, the motor score and oriented exploratory activity parameters were higher than in the control group.

This paper reports FT-IR and FT-NIR spectroscopic study of hydrogen bonding between N-mono-substituted caproamides and different ethers (diethyl ether and tetrahydrofuran) in carbon tetrachloride. With increase in ether concentration increase in intensity of red-shifted band, and decrease of intensity of monomer band has been observed. The MIR and NIR spectroscopic characteristics for N-H center dot center dot center dot O hydrogen bonded complexes and also the equilibrium constants for 1:1 complex formation are given. Further, influence of structural differences of ethers on hydrogen bonding was investigated using Taft equation. Good correlation between logarithm of formation constants and Taft steric and inductive factors has been obtained only for tetrahydrofuran in MIR range.

Phytochemicals are inevitable part of human civilization. It is impossible to say exactly when menfolk started to take plant portions to cure various diseases. Phytochemical investigation of diethyl ether and ethanol extracts of Magnolia grandiflora green seed cones has been carried out. Extraction, isolation, and identification of the phytochemicals were carried out. Structures were determined by various analytical methods including extensive nuclear magnetic resonance, gas chromatography‐mass spectroscopy, and X‐ray crystallographic analyses. Structures of the three compounds viz. 5,5′‐diallyl‐[1,1′‐biphenyl]‐2,2′‐diol (I), 3′,5‐diallyl‐[1,1′‐biphenyl]‐2,4′‐diol (II), and (3S,3aS,8S,9aS,10aR,10bS,E)‐8‐hydroxy‐3,6,9a‐trimethyl‐3a,4,5,8,9,9a,10a,10b‐octahydrooxireno[2′,3′:9,10]cyclodeca[1,2‐b]furan‐2(3H)‐one (III) were confirmed by X‐ray crystallographic analysis. GS‐MS studies of the isolated oil, eluted with hexanes, revealed the presence of eight compounds including two highly bio‐privileged molecules 5,5′‐diallyl‐2′‐methoxy‐[1,1′‐biphenyl]‐2‐ol (IV) and 1‐(4‐isopropylbenzyl)‐1,3‐dihydro‐2H‐benzo[d]imidazol‐2‐one (V). The druggability of the five compounds has also been determined by in silico studies. The isolated compounds and/or their semi‐synthetic products may find application in natural drug development research.

International audience; The reactions of two selected ethers, methyl n-butyl ether (MnBE) and methyl s-butyl ether (MsBE), with three atmospheric oxidants (OH/NO3/Cl) have been investigated at 298 +/- 2 K using the relative rate method and gas chromatography-mass spectrometry. The reaction trends of these short chain aliphatic ethers with the different oxidants have been discussed. From the obtained results, the reaction with OH is the main tropospheric loss process for MnBE and MsBE, with lifetimes of 19.2 h and 26.8 h, respectively. These short lifetimes indicate that the chemistry of these aliphatic ethers is important in areas close to their emission sources.

A procedure of extraction purification of picric acid from impurities of dinitrophenols with diethyl ether at pH = 3 has been developed. Purified picric acid was used to determine the creatinine by the Jaffe reaction on model systems and the extraction-photometric determination of the basic substance in higher quaternary ammonium (QAS) and amine impurities in them. It was shown that both the purity and the concentration of picric acid affect the sensitivity of the creatinine quantification. It was found that to determine creatinine, a solution of HPic with a concentration of 0,035 mol/l should be used. The determination of amines in the QAS and basic substance is also necessary to be carried out only with purified picric acid to avoid distortion of the results.

The addition of 2-bromobenzylmagnesium bromide to chiral N-tert-butanesulfinyl imines derived from tetralone-type ketones proceeds with high levels of diastereocontrol. The resulting sulfinamide derivatives were transformed into dibenzoazaspiro compounds after a palladium-catalyzed intramolecular N-arylation. DFT calculations have been performed to rationalize the stereochemical course of the reaction. Similar results have been obtained considering either diethyl ether or toluene as a solvent, in both cases in an excellent agreement with experimental findings. NCI topological calculations have also been used to evidence crucial noncovalent interactions. In addition, the azaspiro compounds reduced the viability of chronic myeloid leukemia cells in the micromolar range. Notably, both the halogen-substituted (R)- and (S)-8g and -8h as well as (R)-8j were at least two times more effective on a multidrug-resistant derivative than on the parental cell line, exerting a collateral sensitivity effect. We acknowledge the continued financial support from the Spanish Ministerio de Economía y Competitividad (MINECO; project CTQ2014-53695-P, CTQ2014-51912-REDC, CTQ2016-81797-REDC, CTQ2016-76155-R, CTQ2017-85093-P), FEDER, the Generalitat Valenciana (PROMETEOII/2014/017), and the University of Alicante. We thankfully acknowledge the resources from the supercomputers “Memento” and “Cierzo” and technical expertise and assistance provided by BIFI-ZCAM (Universidad de Zaragoza, Spain). We also thank Prof. Vivian M. Rumjanek for providing FEPS cells and Prof. Adriano D. Andricopulo for the preliminary cytotoxicity screening. This study was also financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.

New tetracyclic dispiro-1,2,4-trioxolanes (ozonides) were synthesized by reactions of 5–7-membered alicyclic 1,5-diketones with 30% hydrogen peroxide in diethyl ether or ethanol in the presence of boron trifluoride-diethyl ether complex or a strong mineral acid (HCl, H2SO4, HClO4). Mass spectrometric study of the title compounds under atmospheric pressure chemical ionization revealed specificity of fragment ion decomposition with respect to the ring size, which makes it possible to identify such compounds by their mass spectra.

High catalytic activities (TOF = 3000 h−1) have been achieved by novel water-soluble ruthenium catalysts modified with nitrogen-containing ligands such as the bathophenanthrolinedisulfonic acid disodium salt (BPhDS) in the hydrogenation reaction of the renewable polar platform chemical levulinic acid (LA) which possesses a central relevance in the development of biorefineries of the future in a sustainable way to produce with essentially quantitative selectivity of 99.9 mol% γ-valerolactone (GVL) in aqueous media. The apparent activation energy of the Ru/BPhDS catalyst was calculated and amounts a relative low value of 53.3 kJ/mol when one considers that in the LA hydrogenation reaction this catalyst reduces a less reactive keto group into alcohol functionality. A recycling experiment of the Ru/BPhDS catalyst by extraction after addition of diethyl ether has shown that the catalyst is stable without loss of activity and selectivity in a consecutive run.

Graphical abstract, Highlights • Ultrasonic irradiation of zeolites enhances Si and Al extraction. • Ultrasounds improves mesoporosity of prepared zeolites. • Ultrasonic desilication changes neither the crystallinity nor morphology. • Ultrasonic desilication improves catalytic properties of MFI-type zeolites., In this paper, the ultrasonic-assisted desilication technique was reported as an attractive and efficient way for the preparation of hierarchical zeolites with MFI structure type. The prepared materials were used as active catalysts for the dehydration of ethanol into diethyl ether and ethylene. For all catalysts, the selectivity to diethyl ether was ca 95% or higher up to 210 °C, with catalytic activity in the range of 40–68%. In case of desilicated zeolites, at 270–290 °C, the conversion of ethanol was full with selectivity to ethylene ca 80%. MFI-type commercial zeolite was treated with a sodium and/or tetrabutylammonium hydroxide aqueous solutions (NaOH or NaOH/TBAOH) for 30 min. In the case of the application of ultrasounds, a QSonica Q700 sonicator (60 W and 20 kHz) equipped with a “1” diameter horn was used. In all cases, desilication was performed in an ice bath in order to keep the procedure conditions at low temperature. It was indicated that the use of ultrasounds during desilication procedure caused higher extraction of silicon and aluminum, which was connected with an elevated mesoporosity in relation to the samples modified in the absence of ultrasounds. Ultrasonic-assisted treatment of MFI-type zeolite caused also an apparent formation of numerous holes inside zeolite grains, resembling the look of “swiss cheese”. Furthermore, it was indicated that the samples prepared using ultrasonic irradiation exhibited enhanced catalytic properties in the dehydration of ethanol. For instance, MFI-type zeolite treated with NaOH/TBAOH alkaline mixture containing 10 mol% of TBAOH in the presence of ultrasounds (M−10 s) demonstrated higher both conversion of ethanol (59% vs. 47%) and selectivity to diethyl ether (95% vs. 93%) in comparison with zeolite modified conventionally (M−10c). The best catalyst was zeolite ultrasonically desilicated with NaOH/TBAOH solution of 70 mol% of TBAOH (M-70s). Generally, this catalyst indicated the highest conversion of ethanol, very high selectivity to diethyl ether (94-100%) at 150-210 °C and the highest selectivity to ethylene among investigated catalysts (21%, 66% and 84%) at 230 °C, 250 oC and 270 °C.

© 2020 Elsevier LtdThe aim of this study is to model the HCCI engine performance and exhaust emissions characteristics fueled with fusel oil/diethylether fuel as a renewable fuel by employing the response surface method. The effect of independent variables —different concentrations of fusel oil/diethylether fuel, engine speed, and lambda value — on the response parameters including engine torque, BSFC, COV imep, MPRR, along with CO2, CO, NOX, and UHC were investigated and estimated by multi-regression models. To determine an optimal combination of engine working condition, the desirability function approach was used. High desirability of 82% was achieved at the diethyl ether ratio of 41.72%, the engine speed of 884 rpm, and the lambda value of 2.08. This engine working condition was recommended as the optimum response variables for the HCCI engine having 11.80 Nm of torque, 1.36% of COVimep, 3.14 of MPRR, BSFC of 268 g/kWh, CA10 of 7.52, and CA50 of 11. Besides, the optimal value for engine-out emissions was found to be 0 ppm for NOX, 243.11 ppm for UHC, 6.09 (%Vol.) for CO2, and 0.2 (%Vol.) for CO emissions. The outcomes of this study indicated that all multi-regression models developed by the RSM method could successfully estimate the variations of both engine performance indicators and exhaust emissions.

The title compound was synthesized by electrophilic cyanation of commercially available (R)-4-chloro-α-methylbenzylamine with cyanogen bromide in diethyl ether, and isolated as a yellow oil in 84% yield. It was characterized by 1H and 13C{1H] NMR, IR, HRMS, and specific rotation measurements.

Refining of industrial lignin to produce homogeneous fractions is essential for high-value applications. However, the understanding of key interactions between a variety of solvents with lignin polymer is still uncertain. In this work, single-step fractionation of industrial hardwood kraft lignin (HKL) using organic solvents of different polarities - ethanol, acetone, diethyl ether and hexane - was investigated by combining an experimental and theoretical approach. Experimental results revealed that higher polarity solvents (ethanol and acetone) exhibited higher solubility yield compared to moderate and low polarity solvents. The chemical differences between lignin fractions were proven by pyrolysis gas chromatography mass spectrometry and near infrared spectroscopy. Density functional theory (DFT) results indicated that ethanol presented higher interaction energy followed by acetone, diethyl ether and hexane, which was consistent with experimental findings. Hydrogen bond and non-covalent interaction results from DFT demonstrated that the predominant interaction was found for high polarity of ethanol over other solvents and gamma-OH in the lignin model is the key site. The authors gratefully acknowledge the European Commission for funding the InnoRenew project [Grant Agreement #739574] under the Horizon2020 Widespread-Teaming program, the Republic of Slovenia (investment funding from the Republic of Slovenia and the European Union European Regional Development Funds) and infrastructural ARRS program IO-0035. Additionally, O.G. is grateful for the financial support received from the University of the Basque Country (post-doctoral grant DOCREC18/29) and R.H. acknowledges to the Department of Education of the Basque Government (post-doctoral grant INGVTCL4-D00112-7).

Diazomethane is a yellowish-colored gas with a musty odor. It becomes explosive in nature on contact with metal or a rough glass surface. It is widely used at industrial scale but with special precautions. Diazomethane is also called azimethylene or diazirine and is the most versatile reagent in synthetic organic chemistry. It decomposes into water and alcohol; consequently, it is used in the form of a solution in the presence of diethyl ether. It is mainly used for the fabrication of carbon–heteroatom and carbon–carbon bonds. It is a strong irritant and in high concentration causes various health effects. Hence, it is essential to have adequate knowledge of diazomethane. Included in this chapter is information concerning the risk of exposure, risk assessment, and environmental and health hazards of diazomethane.

The composition of Rhodiola rosea L. lipophylic substances was studied. Acidic and neutral components were identified by gas-chromatography-mass-spectrometry. With methyl-tert-butyl ether as an extractant instead of the volatile solvent diethyl ether, lipophylic extract was obtained. Methyl-tert-butyl ether used as an extraction solvent for raw materials has all the advantages of diethyl ether, being free of its disadvantages. It does not form peroxides or produce elevated partial gas pressure due to its higher boiling point. As a result, comparison with databases identified some triterpene and aliphatic acids with chain lengths 12 to 30 carbon atoms, including saturated, unsaturated, and dibasic acids. In addition to the components known from the literature, more than 50 triterpene and aliphatic compounds were detected in the unsaponifiable residue for the first time.