Aqueous solubility data for pressurized hot water extraction for solid heterocyclic analogs of anthracene, phenanthrene and fluorene

On the Importance of Noncovalent Interactions in the Stabilization of Nonconventional Compounds Using Bulky Groups

In this article, we studied the capability of bulky groups to contribute to the stabilization of a given compound in addition to the well-known steric effect related to substituents due to their composition (alkyl chains and aromatic groups, among others). For this purpose, the recently synthesized 1-bora-3-boratabenzene anion which contains large substituents was analyzed by means of the independent gradient model (IGM), natural population analysis (NPA) at the TPSS/def2-TZVP level, force field-based energy decomposition analysis (EDA-FF) applying the universal force field (UFF), and molecular dynamics calculations under the GFN2-xTB approach. The results indicate that the bulky groups should not only be considered for their steric effects but also for their ability to stabilize a system that could be very reactive.

A Systematic Study on the Redox Potentials of Phenazine-Derivatives in Aqueous Media: A Combined Computational and Experimental Work

Phenazines are an emerging class of organic compounds that have been recently utilized in aqueous redox flow batteries, a promising technology for large-scale energy storage. A virtual screening based on density functional theory calculations is used to investigate the redox potentials of around 100 phenazine derivatives in aqueous media containing various electron-donating or electron-withdrawing groups at different positions. The calculations identify the crucial positions that should be functionalized with multiple hydroxy groups to design new anolytes. The combined experimental-computational methodology reported herein guides the development of a new molecule with a record low reversible redox potential as a potential anolyte for aqueous redox flow batteries.

Solubility and Decomposition of Organic Compounds in Subcritical Water

In this article, studies on organic solubility and stability in subcritical water reported during the past 25 years have been reviewed. Data on the solubility and decomposition of organic compounds in subcritical water, a green solvent, are needed in environmental remediation, chemistry, chemical engineering, medicine, polymer, food, agriculture, and many other fields. For solubility studies, the experimental systems used to measure solubility, mathematical equations derived and applied for the modeling of the experimentally determined solubility data, and the correlation between the predicated and experimental data have been summarized and discussed. This paper also reviewed organic decomposition under subcritical water conditions. In general, the solubility of organics is significantly enhanced with increasing water temperature. Likewise, the percentage of organic decomposition also increases with higher temperature.

Predicting Solubility Limits of Organic Solutes for a Wide Range of Solvents and Temperatures

The solubility of organic molecules is crucial in organic synthesis and industrial chemistry; it is important in the design of many phase separation and purification units, and it controls the migration of many species into the environment. To decide which solvents and temperatures can be used in the design of new processes, trial and error is often used, as the choice is restricted by unknown solid solubility limits. Here, we present a fast and convenient computational method for estimating the solubility of solid neutral organic molecules in water and many organic solvents for a broad range of temperatures. The model is developed by combining fundamental thermodynamic equations with machine learning models for solvation free energy, solvation enthalpy, Abraham solute parameters, and aqueous solid solubility at 298 K. We provide free open-source and online tools for the prediction of solid solubility limits and a curated data collection (SolProp) that includes more than 5000 experimental solid solubility values for validation of the model. The model predictions are accurate for aqueous systems and for a huge range of organic solvents up to 550 K or higher. Methods to further improve solid solubility predictions by providing experimental data on the solute of interest in another solvent, or on the solute's sublimation enthalpy, are also presented.

Fate of thianthrene in biological systems

1. Thianthrene is a sulfur-containing tricyclic molecule distributed widely within the macrostructure of hydrocarbon fossil fuels. Identified nearly 150 years ago, its chemistry has been widely explored leading to insights into reaction mechanisms and radical ion formation. 2. It has been claimed to have therapeutic application in the treatment of dermal infections and to interfere with enzyme and nucleic acid function, but appears to have little toxicity. 3. Following its oral administration to the rat, the majority remained within the gastrointestinal tract. After three days, about 88% was detected in the combined excreta with the remainder still within the animal. It is readily taken up into fish from the surrounding aqueous environment and has been placed within the "bioaccumulative category" to be regarded with concern. 4. Mammalian metabolism appeared to be restricted to ring carbon oxidation and subsequent glucuronic acid conjugation. Small amounts of sulfoxide and disulfoxide were also formed. No ring degradation was evident. Microorganisms similarly undertook aromatic ring hydroxylation but were able also to rupture the ring system by attacking the carbon-sulfur linkages and thereby degrading the molecule.

Pressurized hot water extraction (PHWE)

Pressurized hot water extraction (PHWE) has become a popular green extraction method for different classes of compounds present in numerous kinds of matrices such as environmental, food and botanical samples. PHWE is also used in sample preparation to extract organic contaminants from foodstuff for food safety analysis and soils/sediments for environmental monitoring purposes. The main parameters which influence its extraction efficiency are namely the temperature, extraction time, flow rates and addition of modifiers/additives. Among these different parameters studied, temperature is described as the most important one. It is reported that the extraction of certain compounds is rather dependent on pressurized water with different applied temperature. Thus, the stability and reduced solubilities of certain compounds at elevated temperatures are highlighted in this review. With some modifications, a scaled-up PHWE could extract a higher amount of desirable compounds from solid and powdered samples such as plant and food materials. The PHWE extracts from plants are rich in chemical compounds or metabolites which can be a potential lead for drug discovery or development of disease-resistant food crops.