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In the crystalline sponge method, the crucial step for ordering the absorbed guest is soaking of the guest into the pores of the crystalline sponge. Here, we find that the choice of solvent is particularly important for smooth guest soaking and ordering. Moderately polar solvents, such as ketones and esters, which we have previously avoided for the guest-soaking process, efficiently promote diffusion and guest ordering by filling the gaps in the pores through co-crystallization with the guests. Using this modified protocol, we successfully demonstrate the structural analysis of various steroids.

This present study looks at the engine characteristics of beef tallow biodiesel (tallow methyl ethyl ester) produced using methanol–ethanol-based co-solvent transesterification. Unblended samples o...

The co-solvent prepared from glycerol and hydrochloric acid (HCl) was used for producing low molecular weight chitin from lobster shell. Different reaction temperature, time and acid concentration were studied. The results suggested that the effect of reaction temperature and acid concentration on molecular weight of chitin is most remarkable. The physicochemical properties of chitins were intact during co-solvent treatment. At least 5% HCl was necessary for demineralization and deproteinization. Low molecular weight chitin could be obtained by increasing reaction temperature, acid concentration and prolonging time. The optimized condition for production low molecular weight chitin was at 120 °C for 2 h with acid concentration of 7% (55 kDa) or at 150 °C for 2 h with acid concentration of 5% (57 kDa). This method provides a fast strategy to obtain low molecular weight chitin with high purity from lobster shell.

Lignin valorization is significantly hindered by the intrinsic heterogeneity of its complex structures and variability of biomass feedstocks. Fractionation of lignin can overcome these challenges by producing functionally distinct lignin cuts that can be further tailored to end products. Herein, lignin was extracted and depolymerized from poplar by the co-solvent enhanced lignocellulosic fractionation method with renewable THF to obtain CELF lignin. Several solvents were screened to separate soluble and insoluble fractions from the parent CELF lignin. The ethanol soluble portion was then fractionated into different molecular weight cuts via sequential precipitation of the lignin by reducing the concentration of THF. The physicochemical structures of different CELF lignin cuts were elucidated by GPC and NMR techniques. These results suggest that CELF lignin cuts with lower molecular weight contain progressively higher phenolic and carboxylic acid OH groups, which can be more suitable as green antioxidants than the parent lignin.

We herein describe a new protocol for copper-mediated trifluoromethylation of α-diazoesters and α-diazoketones, both using readily available fluoroform-derived CuCF3. The synergistic effect of using 1,4-dioxane as a co-solvent and pyridine as a promoter is revealed. Reaction conditions are mild and easy to handle, allowing the synthesis of a range of α-trifluoromethyl esters and ketones in one-step from α-diazo carbonyl compounds. The ultimate CF3 source is the inexpensive, nontoxic, industrial waste fluoroform.

Transesterification of used cooking oil (UCO) using NaN3/modified clay catalyst and investigation of the acetone effect have been done.The modified clay catalyst was synthesized by destructing the Merauke clay with8M HCl solution, then fusion by NaOH pellet, followed by treating with AlCl3.6H2O, CTAB and distilled water.Then the mixture was regulated to pH of 11.5. Next, the mixture was then poured into a reactor for hydrothermal process at 140 oC for 48 h. The results of the dealumination of clay was characterized byX-ray Fluorescence and the synthesized zeolite was characterized using surface area analyzer and X-Ray Diffraction.The synthesized zeolite was impregnated by NaN3 as a precussor produced the NaN3/modified clay catalyst sample.Rasio of catalyst :UCO : methanol was 1.0 : 20.0 : 13.3 and the ratio of aceton to methanol was 2:1. The transesterificationprocess was carried out at 60 and 65oC. The liquid product was analyzed using Gas Chromatography Mass Spectrometer.The resulted showed that themodified clay had surface area of 5.5685 m2/g, pore volume of 0.0126 cm3/g, and pore diameter of 8.871 nm. The results of measurements with XRD produced a different form of chromatogram and type of mineral. The main mineral was gismondine.In this research, The transesterification of UCO using NaN3/MC catalyst at 60 oC resulted methyl esters of 65.3 wt %.Furthermore, after adding acetone to the same treatment, the resulting methyl ester was 82.7 wt%.The transesterification of UCO at 65 ° C using NaN3/MC catalyst and acetone produced the highest content of methyl esters or biodiesel that was equal to 94.4 wt %.

Self-cross-linked 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCMBP) polymers with tailored pore size distribution (PSD) and average pore width (Wavg) were synthesized via the Friedel-Crafts reaction in 1,2-dichloroethane (DCE) with reactive (benzene) or non-reactive (hexane and cyclohexane) co-solvents. Compared to using only DCE, Wavg increases (up to 450%) with increasing benzene:DCE ratio due to decreases in cross-linking degree. Hexane and cyclohexane induce phase separation and co-solvent trapping in developing polymers, changing PSD and Wavg without altering cross-linking degree. Findings provide a simple technique to synthesize hyper-cross-linked polymers with user-defined PSDs.

The scope of the work carried out is aimed to evaluate the effects of blending methanol in the gasoline pool, particularly octane number and Reid vapor pressure increase when methanol is substituting methyl-tertiary-butyl ether in the formulation of Regular and Premium base gasolines. Isopropyl alcohol and ethanol have been investigated and found to be a promising co-blending alcohol to be mixed in gasoline methanol blends. Isopropyl alcohol is most effective below 3 vol%. Ethanol has been found to be the most promising co-blending alcohol able to reduce the Reid vapor pressure increase by 1.4 psi even with concentrations in the range of 2 vol%. The addition of isopropyl alcohol to the methanol–gasoline blends has shown the ability of a ternary mixture to further reduce the Reid vapor pressure of the finished gasoline and, subject to availability and price of isopropyl alcohol, could be of interest in further formulation studies focused on maximizing the saving on finished gasoline cost by reducing the Reid vapor pressure of base gasoline and/or increasing the methanol content.

The preferential solvation parameters (δx1,3) of dehydroepiandrosterone acetate (DHEA acetate) in three co-solvent mixtures of methanol (1) + ethyl acetate (2), ethanol (1) + ethyl acetate (2), and isopropanol (1) + ethyl acetate (2) were derived from their available solubility data by means of the inverse Kirkwood–Buff integrals method. The values of δx1,3 vary non-linearly with the co-solvent (1) proportion in all the co-solvent mixtures. For the studied systems, the values of δx1,3 are negative in alcohol-rich mixtures, but positive in ethyl acetate-rich mixtures. The preferential solvation magnitude of DHEA acetate by the ethyl acetate is highest in {methanol (1) + ethyl acetate (2)} mixtures at 293.15 K and 303.15 K. While at 313.15 K, it is highest in {isopropanol (1) + ethyl acetate (2)} mixtures. The δx1,3 values are positive indicating that DHEA acetate is preferentially solvated by ethyl acetate. The co-solvent action may be related to the disordered structure of ethyl acetate molecules around the non-polar moieties of DHEA acetate which increases the solvation having maximum values near to x1 = 0.25–0.35 for the three co-solvent mixtures.

Detailed insights into the organocatalytic properties of imidazolium-based ionic liquids (Im-ILs) for transesterification of cellulose with isopropenyl acetate (IPA) are presented. According to model transesterification reactions and their computational analysis, acetate anions of Im-ILs play an essential role in the promotion of the reactions. Mechanistic considerations in the optimization of the protocol of IL-catalyzed transesterification reactions have enabled a significant improvement in reaction conditions and a positive co-solvent effect for cellulose modifications in an imidazolium acetate ionic liquid.

We present here an improved Suzuki–Miyaura cross-coupling in WERSA (Water Extract of Rice Straw Ash). We found that, although the reaction can be run in neat water, use of alcoholic co-solvent dramatically enhances the yield and generates in situ PdNPs during the reaction. The PdNPs were characterized by TEM and powder XRD analysis. The rice straw ash was characterized by EDX, Flame photometry, and Ion-Exchange chromatography to reveal a broad range of active metal species. The chemical analysis reports of ash showed the presence of oxides of K, Na, and Ca, which probably in the presence of water produces the corresponding hydroxides responsible for the basicity.

Furfural, a biomass-derived platform chemical, was produced by acid-catalyzed reaction of alginic acid extracted from brown seaweed. Three acid catalysts, H2SO4, Amberlyst15 and 12-tungstophosphoric acid (H3PW12O40), were compared to evaluate their catalytic performance for the alginic acid conversion. The H3PW12O40 catalyst showed the highest catalytic activity, yielding the maximum furfural yield (33.8%) at 180 °C for 30 min in tetrahydrofuran/water co-solvent. Higher reaction temperature promoted the conversion of alginic acid to furfural, but the transformation of furfural to humin was also accelerated. To our knowledge, this is the highest furfural yield among studies about the direct catalytic conversion of alginic acid. Furthermore, products distribution with time-on-stream was investigated in detail, which led us to propose a reaction pathway.

Because of the necessity of carry out electrolysis reactions with considerable quantity of organic molecules, the balance between solubility of starting material, solution conductivity and electrochemical stability of medium and intermediates are key factors in organic electrosynthesis. HFIP has several properties that favor its use in this research area as solvent, among them, its high hydrogen-bond donor has opened the possibility of fine tuning reactivity, mainly in anodic reactions because of the helpful effect on the stability of positive intermediates. The cost of this solvent has limited its broad application in chemistry, including electrosynthesis, but the possibility of using mixtures with other cosolvents has demonstrated to help to expand its use without losing the beneficial effect on the intermediates. In recent years several HFIP mixtures (HFIP/MeOH, HFIP/CH2Cl2, HFIP/H2O, HFIP/ACN, HFIP/MeNO2) have permitted the control the chemical microstructure of the electrolysis media and have let to adjust the solvent properties to fulfill the necessity of electrosynthesis. In this review will be discussed the general properties of HFIP and the mixtures reported to carry out electrochemical synthetic transformations of organic molecules, as well as the reactions where has been demonstrated the beneficial effect of HFIP solvent mixtures in the control of the electrogenerated intermediates. This approach has succeeded in organic electrosynthesis.

The preferential solvation parameters by ethanol (EtOH) or propylene glycol (PG) of daidzein were derived from their solution thermodynamic properties by means of the inverse Kirkwood-Buff integrals and the quasi-lattice-quasi-chemical (QLQC) methods. According to IKBI method, the preferential solvation parameter by the co-solvent, I´x 1,3 , is negative in water-rich mixtures but positive in co-solvent-rich mixtures in both kinds of systems. This could demonstrate the relevant role of hydrophobic hydration around the aromatic rings in the drug solvation in water-rich mixtures. Furthermore, the more solvation by co-solvent in co-solvent-rich mixtures could be due mainly to polarity effects and acidic behavior of the hydroxyl groups of the compound in front to the more basic solvents present in the mixtures, i.e. EtOH or PG. Otherwise, according to QLQC method, this drug is preferentially solvated by the co-solvents in all the mixtures in both kind of systems.

This paper covers the synthesis and use of a related family of cyclic phosphazene solvents containing terminal unsaturations that are being considered as electrolyte additives in lithium-ion cells. A brief synopsis on the synthesis and purification of these compounds is given. Data will be presented that covers physical and chemical properties of the phosphazenes as well as the properties when blended at various levels with representative organic carbonate baseline solvents. Electrochemical cycling data will be presented using commercially available electrode couples as well as studies focusing on cell performance at early lifetime as well as after repeated cycles. Conclusions regarding the effect of the unsaturated phosphazene compounds and their interaction with various alkyl carbonates, and their effect on cell performance will be presented.

The solubility of N-(4-chlorophenyl)-2-(pyridin-4-ylcarbonyl) hydrazinecarbothioamide (isoniazid analogue) in mono-solvents (water and polyethylene glycol 400 (PEG 400)) and various PEG 400 + water co-solvent mixtures was measured from (298.15 to 338.15) K using the shake flask method. The experimental solubilities were correlated with Apelblat equation and log-linear model of Yalkowsky. The root mean square deviations were observed in the range of 0.007–0.052 for Apelblat equation. However, the mean absolute errors were observed in the range of (0.36–4.94)% for log-linear model of Yalkowsky. Experimental solubilities of isoniazid analogue were correlated well with Apelblat equation and Yalkowsky model. The solubility of isoniazid analogue was observed highest and lowest in pure PEG 400 (0.108 at 298.15 K) and pure water (5.17 × 10−7 at 298.15 K), respectively. Based on solubility results, isoniazid analogue has been considered as freely soluble in PEG 400 and practically insoluble in water. The solubility data of this study could be useful in formulation development of isoniazid analogue in pharmaceutical industries.

The preferential solvation parameters of methocarbamol in dioxane + water, ethanol + water, methanol + water and propylene glycol + water mixtures are derived from their thermodynamic properties by using the inverse Kirkwood–Buff integrals (IKBI) method. This drug is sensitive to solvation effects, being the preferential solvation parameter δx1,3, negative in water-rich and co-solvent-rich mixtures, but positive in mixtures with similar proportions of solvents, except in methanol + water mixtures, where positive values are found in all the methanol-rich mixtures. It is conjecturable that the hydrophobic hydration around the non-polar groups in water-rich mixtures plays a relevant role. Otherwise, in mixtures of similar solvent compositions, the drug is mainly solvated by co-solvent, probably due to the basic behaviour of the co-solvents; whereas, in co-solvent-rich mixtures, the preferential solvation by water could be due to the acidic behaviour of water. Nevertheless, the specific solute–solvent interac...

Using ionic liquids as co-solvents may improve reaction media in enzyme-based biotechnological processes. To establish new conditions, large libraries need to be screened for bio-compatibility and protein stabilisation. Using a lipase model, we herein describe a combination of methods leading to an expedited evaluation of 61 different solvent compositions.

Solution thermodynamics and solubility of glibenclamide (GBN) in binary co-solvent mixtures of Transcutol + water at temperature range of 298.15-333.15 K were investigated in present study. The modified Apelblat model was used to predict the solubility of GBN in co-solvent mixtures at various temperatures. The highest and lowest solubility of GBN were observed in pure Transcutol and pure water, respectively. Moreover, all co-solvent mixtures had highest solubility at 333.15 K. The experimental solubility data of GBN was correlated well with the modified Apelblat model at each temperature studied with relative absolute deviation in the range of 0.008-5.903 %. The correlation coefficients in co-solvent mixtures were observed in the range of 0.995-0.999 which indicated good fitting of experimental data with calculated one. The enthalpies and entropies for GBN dissolution were observed in the range of 2.012-38.215 kJ mol(-1) and 6.748-114.709 J mol(-1) K(-1), respectively indicating its dissolution is endothermic and an entropy-driven process. These results indicated that Transcutol can be used as a co-solvent in preformulation studies and formulation development of GBN.

Ethylene glycol has the ability to act as a reactant when employed as a co-solvent for the enzymatic synthesis of ampicillin from (R)-phenylglycine methyl ester and 6-aminopenicillanic acid. The side reaction positively affects yield because its product, (R)-phenylglycine hydroxyethyl ester, is an intermediate for ampicillin synthesis. Biotechnol. Biotechnol. Bioeng. 2014;111: 1054–1058. © 2013 Wiley Periodicals, Inc.

A mild and efficient method for the conversion of alkyl and aryl amines to isothiocyanates via dithiocarbamates has been developed using (CH3)2CO-CS2 as co-solvent and triphosgene as dehydrosulfurization reagent. High yields, mild reaction conditions and excellent functional group compatibility make it become a versatile synthetic method for the preparation of isothiocyanates compared with reported methods. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]

The selective hydrogenation of 1,3-butadiene to 1-butene with toluene as a co solvent is studied experimentally over a NiPdCe/γ-Al2O3 catalyst. To reduce mass transfer limitations, an egg-shell catalyst is used in a fixed-bed reactor for liquid-phase hydrogenation of 1,3-butadiene at 40 °C and two pressure levels, 90 and 210 psig. Experimental results indicate that 1,3-butadiene conversion and selectivity of the hydrogenation process are improved when toluene is added. Conversion of 1,3-butadiene increases from 65% without toluene to 75% for 20% toluene concentration at 90 psig, while for 210 psig the observed increase is from 66% to 81%. The 1,3-butadiene selectivity toward 2-butenes is favored against 1-butene, always with preference for the thermodynamically stable trans-isomer. The 1-butene hydrogenation is controlled, decreasing the loss from 25% to 10% in the presence of toluene a 210 psig. It can be concluded that the toluene presence enhances the 1,3-butadiene selective hydrogenation and controls 1-butene consumption.

Haloalkane dehalogenases are microbial enzymes with a wide range of biotechnological applications, including biocatalysis. The use of organic co-solvents to solubilize their hydrophobic substrates is often necessary. In order to choose the most compatible co-solvent, the effects of 14 co-solvents on activity, stability and enantioselectivity of three model enzymes, DbjA, DhaA, and LinB, were evaluated. All co-solvents caused at high concentration loss of activity and conformational changes. The highest inactivation was induced by tetrahydrofuran, while more hydrophilic co-solvents, such as ethylene glycol and dimethyl sulfoxide, were better tolerated. The effects of co-solvents at low concentration were different for each enzyme-solvent pair. An increase in DbjA activity was induced by the majority of organic co-solvents tested, while activities of DhaA and LinB decreased at comparable concentrations of the same co-solvent. Moreover, a high increase of DbjA enantioselectivity was observed. Ethylene glycol and 1,4-dioxane were shown to have the most positive impact on the enantioselectivity. The favorable influence of these co-solvents on both activity and enantioselectivity makes DbjA suitable for biocatalytic applications. This study represents the first investigation of the effects of organic co-solvents on the biocatalytic performance of haloalkane dehalogenases and will pave the way for their broader use in industrial processes.

The impact of varying percentages of an organic solvent added to reactions run in aqueous nanomicelles as the reaction medium has been investigated. Issues such as rates of reaction, percent conversion, and yield, as well as various practical aspects (e.g., effect on stirring, etc.), are discussed, leading to an operationally simple method for the general improvement of potentially problematic systems across a broad range of reaction types, in particular for reactions run at scale.

Solvent intensification for aromatic alcohol oxidation was performed by experimentally extensive screening. A co-solvent mixture of [Omim]Cl and toluene was found to significantly intensify this class of reactions with high conversion of alcohols (> 90%) and high selectivity to their aldehydes (> 90%). The intensification effect can be jointly attributed to the interaction of [Omim]Cl with the catalyst WO3 surface, which enhances its catalytic reactivity, and to the aqueous–organic biphasic formation by toluene, which inhibits the over-oxidation of aromatic alcohols.

The Suzuki–Miyaura reaction has been performed using a phosphine-free perfluoro-tagged palladium catalyst that is readily immobilized on fluorous silica gel through fluorous–fluorous interactions (Pd- 1 /FSG). The reactions are carried out under aerobic and phosphine-free conditions with excellent to quantitative product yields, and very low palladium content (

A new fluorous nano-palladium catalyst was prepared and characterized. The catalytic activity of the catalyst has been evaluated for the Suzuki reaction of aryl halides and aryl boronic acids to afford the corresponding products in high yields. The reaction proceeded smoothly in the presence of 0.1 mol% catalyst in EtOH/H2O at room temperature. In addition, the catalyst could be recovered by fluorous liquid–liquid separation and reused for three times without significant loss of activity. The Suzuki reaction catalyzed by a new fluorous nano-palladium catalyst to afford the products in high yields at room temperature has been described. The catalyst can be recovered by fluorous liquid–liquid separation and reused for several times without significant loss of activity.

The “Noyori” Ru-BINAP chiral complex is an industrially used homogeneous catalyst for stereoselective hydrogenations providing valuable fine chemicals with high optical yields. Its pseudo-immobilisation with help of various ionic liquids (ILs) represents an alternative to the not very efficient heterogenisation on inorganic supports. Many ILs are commercially readily available or could simply be produced, but in both cases a problem of their purity is encountered. Presence of even trace impurities may either suppress or promote the reaction progress, and most importantly, the parameter of enantioselectivity. The complex treatment of the reaction system must be always accepted whenever a genuine role of an ionic liquid is discussed. For this purpose a well understood reaction system—asymmetric hydrogenation of methyl-3-oxobutanoate (methylacetoacetate/MAA) to methyl-3-hydroxybutanoate (methylhydroxybutyrate/MHB) over the chiral Noyori type Ru-BINAP catalyst in the ethanol–bmimPF6 reversibly biphasic mixed phase was chosen. Self-prepared bmimPF6 ionic liquid was exposed to a series of normalized purification steps based on a theoretical semi-mechanistic model. It provided a clear evidence of the number and duration of necessary purification steps together with an effective “value” of each of them. Another important data were collected in the form of pseudo-ternary phase diagrams for all major components including the model impurities.

Co-solvents can minimize two of the major problems associated with the use of ionic liquids (ILs) as solvents for homogeneous derivatization of cellulose: high viscosity and limited miscibility with non-polar reagents or reaction products. Thus, the effects of 18 solvents and 3 binary solvent mixtures on cellulose solutions in three ILs were systematically studied with respect to the solution phase behavior. The applicable limits of these mixtures were evaluated and general guidelines for the use of co-solvents in cellulose chemistry could be advanced: Appropriate co-solvents should have values (normalized empirical polarity) > 0.3, very low “acidity” (α

Attention is called for a superb strategy of peptide synthesis in solution, making use of (per) silylated amino acid fragments. This old methodology may thus present renewed interest if the classical silylation is substituted by silyl cyanides during coupling. Thus, trimethylsilyl cyanide, by its pronounced silylating power affording only gaseous following-(by) products and by its excellent solubilizing properties in organic solvents, overcomes the difficulties and drawbacks that were encountered in previously described strategies that made use of extempore prepared (per) silylated amino acid residues.

There is a need to develop high-performance cellulose fibers as sustainable replacements for glass fibers, and as alternative precursors for carbon filaments. Traditional fiber spinning uses toxic solvents, but in this study, by using dimethyl sulfoxide (DMSO) as a co-solvent with an ionic liquid, a novel high-performance fiber with exceptional mechanical properties is produced. This involves a one-step dissolution, and cost-effective route to convert high concentrations of low molecular weight microcrystalline cellulose into high stiffness cellulose fibers. As the cellulose concentration increases from 20.8 to 23.6 wt%, strong optically anisotropic patterns appear for cellulose solutions, and the clearing temperature (T c) increases from ≈100 °C to above 105 °C. Highly aligned, stiff cellulose fibers are dry-jet wet spun from 20.8 and 23.6 wt% cellulose/1-ethyl-3-methylimidazolium diethyl phosphate/DMSO solutions, with a Young's modulus of up to ≈41 GPa. The significant alignment of cellulose chains along the fiber axis is confirmed by scanning electron microscopy, wide-angle X-ray diffraction, and powder X-ray diffraction. This process presents a new route to convert high concentrations of low molecular weight cellulose into high stiffness fibers, while significantly reducing the processing time and cost.

Asymmetric epoxidation of 3-chloropropene can be catalyzed by chloroperoxidase (CPO) from Caldariomyces fumago to prepare ( R )-epichlorohydrin (ECH) in homogenous phosphate buffer/ionic liquid mixtures using t -butyl hydroperoxide (TBHP) as O 2 donor. Reaction conditions were optimized by the investigation of the choice of oxidants, the presence of ionic liquids (ILs), pH effect and CPO consumption. The best ECH yield reached 88.8% within a duration of 60 min with high enantiomeric excesses (e.e. 97.1%) at pH 5.5 and room temperature, using 1-ethyl-3-methylimidazolium [EMIM][Br] as co-solvent. The ILs with shorter carbon chain was more efficient on chiral ECH preparation.

The transesterification of palm oil in supercritical methanol has been investigated without using any catalyst. HCFC-141b was used as co-solvent to reduce the molar ratio of methanol to palm oil under the milder conditions. The reaction was carried out in a flow-type tubular reactor. The residence time was fixed at 40 min. When the molar ratio of methanol to palm oil was set to 20:1 at 325 °C and 35 MPa, the optimum molar ratio of methanol to co-solvent was found to be 20:1. Addition of HCFC-141b increased FAME production even at the lower molar ratio of methanol to palm oil. In addition, a similar FAME content was obtained under the milder conditions (5 MPa lower pressure) compared with conditions without co-solvent at higher pressure. The role of HCFC-141b in the transesterification reaction under supercritical conditions was investigated.

Effects of selected ionic liquids on the efficiency of CPO oxidation of methyl-parathion were studied. In general, the activity of CPO decreases with the increased concentration of ionic liquid. For ionic liquids with the same cation, those with PF6 − exhibit strongest inhibition toward CPO, while those with either BF4 − or metSO4 − show relatively lesser inhibition. It was further demonstrated that even for buffer solutions containing up to 30% concentration of ionic liquids such as EAN, BMIMmetSO4, and EtPyTFA, CPO still can retain high activity (70–100% compared to that in citrate buffer) for oxidation of methyl-parathion. Photothermal enhancement factors of 3.5 times and corresponding improvements of sensitivity in the determination of organophosphates by the FIA-TLS method are predicted in 30% ionic liquids.

Addition of co-solvents such as tetrahydrofuran resulted in a great improvement of the enantioselectivity of lipase-catalyzed hydrolysis of butyl 2-(4-substituted phenoxy)propanoates in an aqueous ...

The potential of ten different crosslinkers was investigated, with the aim of improving the performance of polymer gel dosimeters used for detecting radiation dose distributions generated by cancer radiation therapy equipment. Unfortunately, none of the candidate crosslinkers was shown to be more effective than N,N'-methylene-bisacrylamide, the standard crosslinker used in polymer gel dosimetry applications. Two co-solvents, glycerol and isopropanol, were used to increase the solubility of N,N'-methylene-bisacrylamide crosslinker in polymer gel dosimeter recipes. Using isopropanol, the crosslinker solubility increased from approximately from 3 to 10% by weight, enabling the manufacture of polymer gel dosimeters with much higher levels of crosslinking than was previously possible. The new dosimeter recipes can be imaged effectively using nuclear magnetic resonance and optical techniques, and may be suitable for read-out using x-ray CT (Computed Tomography).

Direct esterification of citronellol and lauric acid catalyzed by immobilized lipase B from Candida antarctica was performed in supercritical carbon dioxide with different organic solvents and ionic liquids serving as co-solvents. The highest concentration of citronellol laurate after 1 h of reaction performance (3.95 mmol/g substrates) was obtained in SC CO 2 with ethyl methylketone serving as a co-solvent. The optimal temperature and pressure for citronellol laurate synthesis in SC CO 2 /EMK medium was determined to be 60 °C and 10 MPa.

The esterification reaction of phthalic anhydride with methanol was performed at different temperatures in a continuous flow glass microreactor at pressures up to 110 bar and using supercritical CO(2) as a co-solvent. The design is such that supercritical CO(2) can be generated inside the microreactor. Substantial rate enhancements were obtained, viz. a 53-fold increase was obtained at 110 bar and 60 degrees C. Supercritical CO(2) as a co-solvent gave rise to a 5400-fold increase (both with respect to batch experiments at 1 bar at the same temperature).