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Aqueous solubilities of five N-(diethylaminothiocarbonyl)benzimido derivatives at T = 298.15 K

Publication . Schröder, Bernd; Martins, Mónia A.R.; Coutinho, João A.P.; Pinho, Simão

N-(diethylaminothiocarbonyl)benzimido derivatives are polar multifunctional substances. A set of these compounds was synthesised by successive substitution on the enamine side, resulting in similar substances with different polarities, providing a set of model compounds with respect to the study of substituent effects on physico-chemical properties. Experimental aqueous solubility data, at T = 298.15 K, of N-(diethylaminothiocarbonyl)benzamidine, PhCNH2NCSNEt2 (1),N-(diethylaminothiocarbonyl)-N'-phenylbenzamidine, PhCNHPhNCSNEt2 (2), N-(diethylaminothiocarbonyl)-N'-monoethylbenzamidine, PhCNHEtNCSNEt2 (3), N-(diethylaminothiocarbonyl)-N',N'-diethylbenzamidine, PhCNEt2NCSNEt2 (4), and N-(diethylaminothiocarbonyl)benzimido ethylester, PhCOEtNCSNEt2 (5) were measured at T = 298.15 K. The obtained data are supplemented by COSMO-RS aqueous solubility predictions as well as other environmentally important partition coefficients. This information is shown in a two-dimensional chemical space diagram, providing indications about the compartment into which the bulk of the compounds is likely to concentrate. The expected quality of COSMO-RS predictions for this type of screening exercise is illustrated on a set of pesticides with established thermophysical property data.

2016Journal article

Restricted access

Selection of ionic liquids to be used as separation agents for terpenes and terpenoids

Publication . Martins, Mónia A.R.; Domańska, Urszula; Schröder, Bernd; Coutinho, João A.P.; Pinho, Simão

In this work, ionic liquids are evaluated for the first time as solvents for extraction and entrainers in separation processes involving terpenes and terpenoids. For that purpose, activity coefficients at infinite dilution, γ13 ∞, of terpenes and terpenoids, in the ionic liquids [C4mim]Cl, [C4mim][CH3SO3], [C4mim][(CH3)2PO4] and [C4mim][CF3SO3] were determined by gas−liquid chromatography at six temperatures in the range 398.15 to 448.15 K. On the basis of the experimental values, a correlation of γ13 ∞ with an increase of the solubility parameters is proposed. The infinite dilution thermodynamic functions were calculated showing the entropic effect is dominant over the enthalpic. Gas−liquid partition coefficients give indications about the recovery and purification of terpenes and terpenoids from ionic liquid solutions. Presenting a strong innovative character, COSMO-RS was evaluated for the description of the selectivities and capacities, showing to be a useful tool for the screening of ionic liquids in order to find suitable candidates for terpenes and terpenoids extraction, and separation. COSMO-RS predictions show that in order to achieve the maximum separation efficiency, polar anions should be used such as bis(2,4,4-trimethylpentyl)phosphinate or acetate, whereas high capacities require nonpolar cations such as phosphonium.

2016Journal article

Restricted access

Physico-chemical property prediction and environmental fate modelling of N-acylchalcogenourea derivatives

Publication . Schröder, Bernd; Martins, Mónia A.R.; Pinho, Simão; Coutinho, João A.P.

(Subcooled) vapour pressures, aqueous solubilities, Henry constants, log KOW and log KOC partition constants have been estimated for a set of N-acyl-chalcogenourea derivatives using several prediction methods (COSMO-RS in its COSMOtherm implementation, SPARC as well as EPA’s EPIsuite). The data are discussed in terms of substituent effects: how do subtle changes in the chemical composition influence basic physico-chemical properties and hence, the environmental fate of the title compounds?

2013Conference object

Open access