Solvatochromic Linear Solvation Energy Relationships (LSER) for Solubility of Gases in Various Solvents by Target Factor Analysis

A linear solvation free energy relationship has been conducted to study the effects of solvent and solute properties on the free energy of solvation of inert gases and normal alkanes in different solvents. Factor analysis combined with target factor analysis was used to identify and quantify the factors controlling the variation of free energies of solvation, without the need to postulate any priori hypothetical method. Factor analysis of the solvation data revealed that there are two factors affecting the solubility of both types of gases in non‐polar as well as polar solvents. Target testing of the solvent parameters indicated that the Hildebrand solubility parameter of solvents is the major factor controlling the solubility of gases. Moreover, it was found that the coefficient of the Hildebrand solubility parameter in the linear solvation free energy equations has linear correlation with energy of vaporization and Lennard‐Jones force parameter of inert gases and number of carbon atoms and energy of vaporization of normal alkanes.     

利用溶解度参数选择有机溶剂提取土壤中多种有机氯农药

采用基团贡献法计算了提取溶剂（正己烷、二氯甲烷、正己烷—甲醇（体积比4：1)、正己烷—丙酮（体积比1：1)、正己烷—二氯甲烷(体积比1：1))和有机氯农药（o,p′—DDT,o．p′—DDE,o,p′—DDD,α—endosubn,endrin,HCB)的色散溶解度参数(δd)、极性溶解度参数(δp)和氢键溶解度参数(δh),运用溶解度参数的理论筛选有机溶剂提取江西红壤中多种有机氯农药：研究表明正己烷—甲醇（体积比4：1)和正己烷—丙酮（体积比1：1)是提取江西红壤中o,p′—DDT,o,p′—DDE,o,p′—DDD多种有机氯农药的最佳提取溶剂（回收率大于82％),对α—endosulfan,endrin,HCB的提取也能满足检测需要（回收率大于75％)。超声波提取的结果验证了溶解度参数预测的合理性。     

Prediction of Solubility Parameters Based on the Explicit Expression of Statistical Thermodynamics

A robust and efficient procedure is presented for calculating the solubility parameter. An analytical equation for internal pressure is proposed. Through a simple relation reported by Verdier and Andersen (fluid phase equilibrium 231: 125–137, 2005), one can easily find the solubility parameter via our analytical equation for the internal pressure. Also, the radial distribution function (RDF) of a Lennard–Jones LJ (12, 6) fluid, proposed by Xu and Hu (fluid phase equilibrium 30: 221–228, 1986), has been employed to calculate the internal pressure of normal alkanes from methane to decane. Their solubility parameters were evaluated according to the calculated values of the internal pressure. A comparison between the experimental and the estimated values demonstrated a very good agreement between them.     

Solubility Behavior of Pimozide in Polar and Nonpolar Solvents: Partial Solubility Parameters Approach

The solubility behavior of pimozide in individual solvents ranging from nonpolar to highly polar was studied. For understanding the solute-solvent interactions, the partial solubility parameters concept was utilized. Solutions containing excess drug were shaken in a water bath for 72 hours at 25 °C. After the solutions attained equilibrium, they were filtered and analyzed for drug content. A multiple regression method, using extended Hansen’s partial solubility parameters, was applied to verify the solubilities of pimozide in pure polar and nonpolar solvents and to predict its solubility in untested solvents. The three-parameter approach and the Flory-Huggins size correction term ‘B’ give predictions of solubilities with correlations up to 97%. The four-parameter approach involving proton-donor and proton-acceptor parameters was also used in fitting the solubility data. The correlations are appreciable (94%). Further, the ‘B’ term coupled with four-parameter approach was examined in order to improve the data representation, and resulted in a 1% improvement (98%) in the correlation when compared to the Flory-Huggins size-correction method. The solubility parameter obtained by this method is 10.43 H which is closer to the values obtained by theoretical methods, such as Fedors’ and Hoy’s. The resulting partial solubility parameters are δ _2d =8.85 H, δ _2p =2.17 H, δ _2a =3.15 H, and δ _2b =4.08 H, which give insights into the interaction capability of pimozide and are consistent with its chemical structure. Pimozide is a Lewis base as its δ _2b >δ _2a . The total solubility parameter of pimozide is assigned at 10.43 H. This work demonstrates for the first time the validity of the four-parameter approach coupled with the Flory-Huggins size-correction term and therefore the result is interesting.     

Solubility Measurements and Prediction of Coenzyme Q10 Solubility in Different Solvent Systems

The solubility of coenzyme Q10 in ethyl acetate, n-hexane, 1-butanol, 1-propanol, 2-propanol and ethanol in the temperature range 270.15–320.15 K, under atmospheric pressure, was measured by a gravimetric method and compared with the data predicted using the conductor like screening model for realistic solvation (COSMO-RS) method. The results show that the solubilities of coenzyme Q10 in the above solvents increase with temperature. The temperature dependences of predicted solubilities were consistent with the experimental data. The experimental data were correlated with the Apelblat equation. At the same temperature, the order of increasing solubility is ethyl acetate > n-hexane > 1-butanol > 1-propanol > 2-propanol > ethanol.     

基于COSMO-SAC模型计算聚合物的溶解度参数

基于COSMO-SAC模型计算了几类聚合物膜材料与不同溶剂间的Flory-Huggins相互作用参数,利用溶解度参数与相互作用参数间的关系,分别通过线性拟合和最小二乘法获得了Hildebrand溶解度参数和Hansen溶解度参数。与文献值比较,Hildebrand溶解度参数计算结果的相对偏差区间为2.44%~17.31%,平均相对偏差为10.13%。当校正因子α=0.6时得到的Hansen溶解度参数相对偏差较小(6.64%),偏差区间为1.66%~13.60%;而α=1时得到的Hansen溶解度参数相对偏差较大(12.62%),偏差区间为5.56%~19.77%;α=0.6时得到的色散分量和偶极分量相对偏差较小,但氢键分量相对偏差较大。     

Determination and Correlation of the Solubility of Acetylpyrazine in Pure Solvents and Binary Solvent Mixtures

The solubilities of acetylpyrazine in seven pure solvents and one binary solvent mixture were determined by a dynamic analytic method at temperatures ranging from 268.15 to 308.15 K under atmospheric pressure. For pure solvents, the solubility of acetylpyrazine increases with increasing temperature and solvent polarity. For the binary solvent mixture of ethyl acetate and isopropanol, the solubility increases with increasing temperature and mole fraction of ethyl acetate. The solubility data were correlated with some thermodynamic models, including the modified Apelblat model, λh model, CNIBS/R-K model, and NRTL model. In addition, the relationship between solubility and solvent polarity was investigated by using the Arrhenius equation. All the models or equations gave satisfactory correlation results. The results showed that the solubility of acetylpyrazine generally rises with the increase of solvent polarity at the same temperature. Moreover, the dissolution thermodynamic properties of acetylpyrazine in different solvents were calculated and are discussed based on the NRTL model.     

Solubility and Thermodynamic Data of Febuxostat in Various Mono Solvents at Different Temperatures

This study examines the solubility and thermodynamics of febuxostat (FBX) in a variety of mono solvents, including “water, methanol (MeOH), ethanol (EtOH), isopropanol (IPA), 1-butanol (1-BuOH), 2-butanol (2-BuOH), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), ethyl acetate (EA), Transcutol-HP (THP), and dimethyl sulfoxide (DMSO)” at 298.2–318.2 K and 101.1 kPa. The solubility of FBX was determined using a shake flask method and correlated with “van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models”. The overall error values for van’t Hoff, Buchowski-Ksiazczak λh, and Apelblat models was recorded to be 1.60, 2.86, and 1.14%, respectively. The maximum mole fraction solubility of FBX was 3.06 × 10⁻² in PEG-400 at 318.2 K, however the least one was 1.97 × 10⁻⁷ in water at 298.2 K. The FBX solubility increased with temperature and the order followed in different mono solvents was PEG-400 (3.06 × 10⁻²) > THP (1.70 × 10⁻²) > 2-BuOH (1.38 × 10⁻²) > 1-BuOH (1.37 × 10⁻²) > IPA (1.10 × 10⁻²) > EtOH (8.37 × 10⁻³) > EA (8.31 × 10⁻³) > DMSO (7.35 × 10⁻³) > MeOH (3.26 × 10⁻³) > PG (1.88 × 10⁻³) > EG (1.31 × 10⁻³) > water (1.14 × 10⁻⁶) at 318.2 K. Compared to the other combinations of FBX and mono solvents, FBX-PEG-400 had the strongest solute-solvent interactions. The apparent thermodynamic analysis revealed that FBX dissolution was “endothermic and entropy-driven” in all mono solvents investigated. Based on these findings, PEG-400 appears to be the optimal co-solvent for FBX solubility.     

应用人工神经网络预测氢化可的松的溶解度

以量子化学方法在密度泛函B3LYP/6-31G(d)水平上计算得到含有电负性原子的溶剂水、醇类、酮类、酯类、氯代烷烃共17种溶剂的结构参数：最高占用轨道能(EHOMO)、分子最低空轨道能(ELUMO)、分子偶极矩(μ)、分子总能量(Etotal) 、最正原子净电荷(q+)、最负原子净电荷(q-)。采用误差反向传播(BP)算法的三层人工神经网络,确定隐含层节点数为7,建立了EHOMO、ELUMO、μ、Etotal、q+、q-、摩尔体积(VM)、介电常数(ε)、温度(T)共9个参数与氢化可的松在不同温度下不同溶剂中的溶解度之间关系的模型。运用此神经网络模型可预测不同分离条件下氢化可的松的溶解度,平均预测相对误差为7.0%。     

Solubility and Thermodynamic Properties of A Hexanediamine Derivative in Pure Organic Solvents and Nonaqueous Solvent Mixtures

The solubility of N,N′-Bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,6-hexanediamine in seven pure solvents (acetonitrile, acetone, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate and isobutyl acetate) and two binary solvent mixtures (acetone?+?acetonitrile and methyl acetate?+?acetonitrile) were measured from 273.15 to 303.15 K at atmospheric pressure by a dynamic method. The solubility data in these pure solvents were correlated by the modified Apelblat model, the Wilson model and the NRTL model, and that in the binary solvents mixture were fitted to the CNIBS/R–K model and the NRTL model. Furthermore, the mixing thermodynamic properties in pure and binary solvent systems were calculated and are discussed, based on the NRTL model. Finally, the applicability of the model of Zhang et al. (Ind Eng Chem Res 51:6933–6938, 2012) in correlating solubility data versus dielectric constant was extended from organic solvent–water mixtures to pure organic solvents and nonaqueous organic solvent mixtures. It was found that the dissolution behavior of a compound in the binary solvent mixtures can be predicted to some extent from those in pure solvents.     

Ion-Pair Solvent Extraction of EDTA Anions with Tetraalkylammonium Ions in Various Organic Solvents

Summary.  The ion-pair solvent extraction behavior of ethylenediaminetetraacetate (EDTA) anion by various tetraalkylammonium ions was investigated at 25.0 ± 0.1°C. The extraction of EDTA exceeded 90% from the basic aqueous solution into the organic solvents such as n-hexane and benzene derivatives containing tri-n-octylmethylammonium chloride, but EDTA was hardly extracted from acidic solution. Among the chemical species of EDTA in aqueous solution, edta ⁴⁻ is the most extractable one. On the other hand, the extraction of EDTA was less than 1% into chloroform and 1,2-dichloroethane even from the basic aqueous solution. The effect of the structure of alkylammonium ion was also examined. Tetra-n-hexylammonium and tetra-n-octylammonium ions could not extract EDTA even from the basic aqueous solution, while the use of tri-n-octylmethylammonium and di-n-lauryldimethylammonium ions enhances the extraction of EDTA. These results suggest that the steric hindrance in the ion-pair of alkylammonium and EDTA anion in the organic phase affects the extractability of EDTA containing ion-pair. The solution structure of ion-pair in the organic phase was calculated by MMFF force field and the steric effect in the ion-pair was also suggested. From the extraction constants obtained, the possibility of the extraction separation of EDTA has been shown. Present address: Chemistry Department, Heilongjiang University, Harbin, China     

Empirical Model of Solvophobic Interactions in Organic Solvents

An empirical model was developed to predict organic solvophobic effects using N-phenylimide molecular balances functionalized with non-polar alkyl groups. Solution studies and X-ray crystallography confirmed intramolecular alkyl-alkyl interactions in their folded conformers. The structural modularity of the balances allowed systematic variation of alkyl group lengths. Control balances were instrumental in isolating weak organic solvophobic effects by eliminating framework solvent-solute effects. A ¹⁹F NMR label enabled analysis across 46 deuterated and non-deuterated solvent systems. Linear correlations were observed between organic solvophobic effects and solvent cohesive energy density (ced) as well as changes in solvent-accessible surface areas (SASA). Using these empirical relationships, a model was constructed to predict organic solvophobic interaction energy per unit area for any organic solvent with known ced values. The predicted interaction energies aligned with recent organic solvophobic measurements and literature values for the hydrophobic effect on non-polar surfaces confirmed the model‘s accuracy and utility.     

Ion-Pair Solvent Extraction of EDTA Anions with Tetraalkylammonium Ions in Various Organic Solvents

The ion-pair solvent extraction behavior of ethylenediaminetetraacetate (EDTA) anion by various tetraalkylammonium ions was investigated at 25.0 ± 0.1°C. The extraction of EDTA exceeded 90% from the basic aqueous solution into the organic solvents such as n-hexane and benzene derivatives containing tri-n-octylmethylammonium chloride, but EDTA was hardly extracted from acidic solution. Among the chemical species of EDTA in aqueous solution, edta ⁴⁻ is the most extractable one. On the other hand, the extraction of EDTA was less than 1% into chloroform and 1,2-dichloroethane even from the basic aqueous solution. The effect of the structure of alkylammonium ion was also examined. Tetra-n-hexylammonium and tetra-n-octylammonium ions could not extract EDTA even from the basic aqueous solution, while the use of tri-n-octylmethylammonium and di-n-lauryldimethylammonium ions enhances the extraction of EDTA. These results suggest that the steric hindrance in the ion-pair of alkylammonium and EDTA anion in the organic phase affects the extractability of EDTA containing ion-pair. The solution structure of ion-pair in the organic phase was calculated by MMFF force field and the steric effect in the ion-pair was also suggested. From the extraction constants obtained, the possibility of the extraction separation of EDTA has been shown.     

一种计算水溶解度的经验加合模型的适用范围与局限

我们发展了一种用于预测有机小分子化合物水溶解度(logS)的经验方法XLOGS. 它本质上是一种加合模型, 采用83种原子/基团类型和3个校正因子作为模型的描述符.该方法还可以根据一个合适的参照分子的logS实验值来计算未知化合物的logS值. 我们将XLOGS模型在由4171个化合物组成的训练集上进行了参数化, 多元线性回归获得的相关系数R²和标准偏差SD分别为0.82和0.96单位. 将该训练集进一步分为仅含液体化合物和仅含固体化合物的两个子集. XLOGS模型在这两个子集上的回归结果显示前者优于后者(标准偏差分别为0.65单位和0.94单位). 还利用log1/S和logP(脂水分配系数)之间的差值来研究XLOGS方法在液体和固体化合物数据集上的表现. 研究结果表明: XLOGS等加合法模型更适合应用于这两者差值接近于0的化合物. 我们还将XLOGS和其他三种流行的logS计算模型(包括Qikprop, MOE-logS和ALOGPS)在一个含有132个类药化合物的独立测试集上进行了比较. 总体而言, 我们的研究结果为加合法模型在水溶解度预测方面的合理应用提供了指导.     

Solubility of Adipic Acid in Organic Solvents and Water

The solubility of adipic acid in methanol, ethanol, propanol, isopropanol, n-butanol, tert-butanol, acetone, 1,4-dioxane, acetic acid, and water was measured within the 0–60°C temperature range. A sampler for determination of the temperature dependence of the solubility of solids in liquids by the isothermal method was suggested. The thermodynamic parameters of solution of adipic acid in the above solvents were calculated. The dependence of the solubility on the solvent and temperature was considered.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 403–407.Original Russian Text Copyright © 2005 by Gaivoronskii, Granzhan.     

Solubility of Acetyl- and Diacetylferrocene in Mixed Aqueous-Alcoholic Solvents

Solubility of acetyl- and diacetylferrocene in aqueous-alcoholic solvents as a function of temperature was studied. At any composition of the mixed solvent, the solubility of both compounds increases with temperature. The enthalpies and entropies of solution of both compounds are positive.     

Solvent Effects on the Solubility of C60 fullerene

The solubility of C₆₀ fullerene in organic liquids is not directly related to any of their physicohemical characteristics, but can be quantitatively described by linear multiparameter equations. The solubility increases with increasing solvent polarizability and decreases with increasing solvent polarity and cohesive energy density. Various types of multiparameter equations proposed in the literature were compared to show that they all are suitable but Koppel-Palm's equation is preferred.     

Pitzer混合参数对HCl-NaCl-H2O体系溶解度预测的影响

This paper reports the results of solubility calculation of the phase system HCl NaCl H2O at 25 ℃ when θHNa (interactions of two species with the same charge) and ΨHNaCl (interactions of three species) were changed by ＋10％ and －10％. The results indicated that the effects of the two kinds of interactions on the calculated solubility of the system were regular. The calculated solubilities of the system did not vary while the two interactions were increased and decreased simultaneously. The solubility data of the system changed greatly as one interaction was increased and the other decreased. This study is significant for the chemical technology of salting out salts from the water salt system.