Publicaciones 2011-2020

@article{RN376,
title = {Iso-Solvation Effects in Mixtures of Ionic Liquids on the Kinetics of a Model Snar Reaction},
author = { J. Alarcon-Esposito and R. Contreras and P.R. Campodonico},
url = {/brokenurl#<Go to ISI>://WOS:000414440000030},
doi = {10.1039/c7nj03246c},
issn = {1144-0546},
year = {2017},
date = {2017-01-01},
journal = {New Journal of Chemistry},
volume = {41},
number = {22},
pages = {13435-13441},
abstract = {The SNAr reaction between 1-chloro-2,4-dinitrobenzene and morpholine was used as a model system to study solvation effects in a series of mixtures involving imidazolium based ionic liquids. Iso-solvation regimes (i.e. a solvent composition regime where the solute is being solvated by approximately the same number of different solvent molecules in the mixture) are reported for the first time in ionic liquid mixtures, for 4 mixtures including [EMIM][SCN][DCN], [BMIM][DCN][BF4], [BMIM][BF4][PF6] and [BMIM][PF6][FAP]. The results show that for significant changes in composition, the rate coefficients remain approximately constant. An additional interesting result is that the mixture [BMIM][BF4][PF6] (in the proportion of 0.9 for the molar fraction of BMIMBF4) shows a slightly better kinetic performance as compared to pure BMIMBF4 and BMIMPF6. Finally, for the [EMIM][SCN][DCN] mixture, an increasing proportion of EMIMSCN with respect to EMIMDCN results in a decrease in the rate coefficient within the range of (0.1-0.75) for the molar fraction of EMIMSCN. This result may be traced to competition between the anions [SCN-] and [DCN-] towards the reaction center driven by the basicity of the reaction medium.},
keywords = {alpha, aromatic behavior, binary-mixtures, comparison method, nucleophilic-substitution, parameters, preferential probes, scale solvation, solvatochromic solvents},
pubstate = {published},
tppubtype = {article}
}

@article{RN195,
title = {Substituent Effects on Reactivity of 3-Cinnamoylcoumarins with Thiols of Biological Interest},
author = { M.E. Aliaga and W. Tiznado and B.K. Cassels and M. Nunez and D. Millan and E.G. Perez and O. Garcia-Beltran and P. Pavez},
url = {/brokenurl#<Go to ISI>://WOS:000327849700027},
doi = {10.1039/c3ra44695f},
issn = {2046-2069},
year = {2014},
date = {2014-01-01},
journal = {Rsc Advances},
volume = {4},
number = {2},
pages = {697-704},
abstract = {The Michael addition reactions of the biothiols cysteine, homocysteine, cysteinyl-glycine, gamma-glutamylcysteine and glutathione with 3-cinnamoylcoumarin derivatives (ChC1-ChC4) in aqueous solution (30 degrees C, ionic strength 0.2 M KCI) were followed fluorimetrically and evaluated kinetically. The study was completed with a theoretical analysis based on the inverse of the Fukui potential (1/v(f) (r)), which is proposed for the first time as a local softness descriptor. Thus, considering both experimental results and theoretical analysis, the following conclusions can be drawn: (i) the reactivity of the tested probes towards Michael addition increases in the para-substitution sequence: H < OEt < SMe < Br < NO2, and is not correlated with the sigma(P) values of the substituents; (ii) in turn, the descriptor proposed here as local softness (1/v(f) (r)) appears as a promising reactivity index that is able to explain the higher k(N) values found for both electron-withdrawing and electron-donating groups; (iii) the nucleophilic reactivity of the biothiols employed increases in the sequence Cys-Gly < Hcy < GSH < Cys < gamma-Glu-Cys; and also finally (iv) we have demonstrated that these probes can be used for fluorimetric thiol determination in SH-SY5Y cells.},
keywords = {alpha, beta-unsaturated chemical-reactivity, cysteine, density-functional-approach, disease, electrophilicity fluorescent, glutathione, ketones, michael probe, turn-on},
pubstate = {published},
tppubtype = {article}
}