A aplicação das escalas solvatocrómicas a misturas é mais reduzida do que a solventes puros. Um dos problemas da aplicação destas escalas a misturas deve-se ao fenómeno da solvatação preferencial. Saber se a molécula sonda poderá representar de facto a globalidade das interacções presentes na mistura de solventes e não só as suas interacções particulares com um dos componentes da mistura e/ou com espécies complexas presentes no meio, continua a gerar alguma controvérsia.
Esta questão tem sido estudada e discutida por vários autores [78-82] sem que tenham obtido uma resposta satisfatória. Uma das formas para testar a validade da utilização das sondas solvatocrómicas em misturas é a utilização de mais do que uma sonda (com estruturas diferentes) para determinar a mesma propriedade. A proximidade dos valores obtidos por diferentes sondas pode indiciar que (independentemente da solvatação preferencial) se determinou uma propriedade característica da mistura estudada [79].
A solvatação preferencial será discutida em detalhe no próximo capítulo. Apesar da incerteza sobre a aplicação das escalas solvatocrómicas a misturas, as mesmas têm sido cada vez mais utilizadas devido à sua extrema utilidade, por exemplo nas análises de correlação de variadas propriedades fisico-químicas (solubilidade, reactividade, etc.) de solutos numa variedade de solventes e misturas de solventes.
Uma grande parte dos estudos tem incidido sobre misturas aquosas, e de entre as sondas, a mais utilizada é sem dúvida a betaína (30), e a sua correspondente escala solvatocrómica, ET.
Vários grupos de investigação têm-se dedicado ao longo dos anos ao estudo de misturas, entre os quais se destacam os grupos de Bosch, Rosés e colaboradores [83-91], Herodes e colaboradores [92-94] e também Mancini, Vottero e colaboradores [75, 95-102], estes últimos ligados mais a aspectos de reactividade. Também têm sido publicadas compilações de resultados de estudos em misturas, de entre os quais se destacam o artigo de revisão de Reichardt de 1994, relativamente à escala solvatocrómicaET (30) [39], e também as compilações realizadas por Marcus [78-79,
103], mais extensas e versando mais escalas.
Existem já alguns trabalhos publicados sobre algumas das misturas estudadas nesta dissertação, informação que é apresentada na tabela II.5.
Tabela II.5: Estudos solvatocrómicos já realizados nas misturas analisadas neste trabalho.
Mistura Escala solvatocrómica /
sonda (s) Autores / Ano / Referência
Metanol / Acetonitrilo
ET / Betaína (30) Elias et al. / 1981 / [104]
ET / Betaína (30) Koppel e Koppel / 1983 / [105]
ET / Betaína (30) Bosch et al. / 1996 / [86]
ET / Merocianina de Brooker Silva et al. / 2002 / [106]
I /III 11 / Pireno Silva et al. / 2002 / [107]
e / N,N-dietil-4-nitroanilina 4-nitroanisole e 4-nitroanilina Mancini et al. / 2003 / [108] SPP, SA e SB / 2-(dimetil-amino)-7- nitrofluoreno, 2-fluoro-7-nitrofluoreno, 5-nitroindolina, 1-metil-5-nitroindolina, betaína o-tert-butilestilazólio, betaína
o,o’-di-tert-butilestilazólio
Mancini et al. / 2006 / [80]
Metanol / Formamida ET / Betaína (30) Herodes et al. / 1999 / [92]
ET / Merocianina de Brooker Bevilaqua et al. / 2004 / [109]
Acetonitrilo / 1-Propanol ET (1) / Betaína (1) Mehranpou e Hashemnia / 2006 / [110]
É importante referir que a utilização de valores numéricos de escalas solvatocrómicas provenientes de múltiplas fontes constitui sempre um risco, quer em solventes puros quer em misturas. Este processo tem de ser feito de forma cuidadosa e tanto quanto possível evitado, dado que a maior parte dos estudos envolve normalmente diferente(s) indicador(es) para a mesma escala, utilizam-se relações matemáticas distintas para a obtenção do mesmo parâmetro e inclusivamente usam- se condições experimentais diversas. Neste sentido, embora existam alguns trabalhos com algumas das sondas e misturas estudadas nesta dissertação, a opção recaiu na repetição destas determinações de forma a garantir um conjunto homogéneo e coerente de resultados experimentais.
Bibliografia
1. Reichardt, C., Solvents and Solvent Effects in Organic Chemistry. 3rd ed., Wiley-VCH: Weinheim, 2003.
2. Grunwald, E.; Winstein, S., The Correlation of Solvolysis Rates. Journal of the
American Chemical Society, 1948, 70(2), 846-859.
3. Kosower, E.M., The Effect of Solvent on Spectra .1. A New Empirical Measure of Solvent Polarity - Z-Values. Journal of the American Chemical Society, 1958, 80(13), 3253-3260.
4. Chapman, N.B.; Shorter, J., Advances in Linear Free Energy Relationships, Plenum Press: London, New York, 1972.
5. Gutmann, V.; Wychera, E., Coordination Reactions in Non Aqueous Solutions - the Role of the Donor Strength. Inorg. Nucl. Chem. Lett., 1966, 2(9), 257-260. 6. Dimroth, K.; Bohlmann, F.; Reichard, C.; Siepmann, T., Uber Pyridinium-N-
Phenol-Betaine Und Ihre Verwendung Zur Charakterisierung Der Polaritat Von Losungsmitteln. Annalen Der Chemie-Justus Liebig, 1963, 661, 1-37.
7. Kamlet, M.J.; Taft, R.W., Solvatochromic Comparison Method .1. Beta-Scale of Solvent Hydrogen-Bond Acceptor (HBA) Basicities. Journal of the American
Chemical Society, 1976, 98(2), 377-383.
8. Abraham, M.H.; Whiting, G.S.; Doherty, R.M.; Shuely, W.J., Hydrogen-Bonding .13. A New Method for the Characterization of GLC Stationary Phases - the Laffort Data Set. Journal of the Chemical Society-Perkin Transactions 2,
1990(8), 1451-1460.
9. Katritzky, A.R.; Fara, D.C.; Yang, H.F.; Tämm, K.; Tamm, T.; Karelson, M., Quantitative Measures of Solvent Polarity. Chemical Reviews, 2004, 104(1), 175-198.
10. Gutmann, V., Effect of Sovent Donor Number on Chemical and Electrochemical Behavior. Chimia, 1969, 23(8), 285.
11. Leo, A.; Hansch, C., Linear Free-Energy Relationships between Partitioning Solvent Systems. Journal of Organic Chemistry, 1971, 36(11), 1539-1544. 12. Leo, A.; Hansch, C.; Elkins, D., Partition Coefficients and Their Uses. Chemical
Reviews, 1971, 71(6), 525-616.
13. Maria, P.C.; Gal, J.F., A Lewis Basicity Scale for Nonprotogenic Solvents - Enthalpies of Complex-Formation with Boron-Trifluoride in Dichloromethane.
Journal of Physical Chemistry, 1985, 89(7), 1296-1304.
14. Marcus, Y., Linear Solvation Energy Relationships - a Scale Describing the Softness of Solvents. Journal of Physical Chemistry, 1987, 91(16), 4422-4428. 15. Abraham, M.H.; Grellier, P.L.; McGill, R.A., A Quantitative Measure of Solvent
Solvophobic Effect. Journal of the Chemical Society-Perkin Transactions 2,
1988(3), 339-345.
16. Catalán, J.; Gómez, J.; Couto, A.; Laynez, J., Toward a Solvent Basicity Scale - the Calorimetry of the Pyrrole Probe. Journal of the American Chemical Society,
1990, 112(5), 1678-1681.
17. Drago, R.S.; Dadmun, A.P.; Vogel, G.C., Addition of New Donors to the E and C Model. Inorganic Chemistry, 1993, 32(11), 2473-2479.
18. Winstein, S.; Grunwald, E.; Jones, H.W., The Correlation of Solvolysis Rates and the Classification of Solvolysis Reactions into Mechanistic Categories.
Journal of the American Chemical Society, 1951, 73(6), 2700-2707.
19. Winstein, S.; Fainberg, A.H.; Grunwald, E., Correlation of Solvolysis Rates .8. Benzhydryl Chloride and Bromide - Comparison of My and Swains Correlations.
Journal of the American Chemical Society, 1957, 79(15), 4146-4155.
20. Lassau, C.; Jungers, J.C., Influence of Solvent on Chemical Reaction . Quaternisation of Tertiary Amines by Methyl Iodide. Bulletin De La Societe
21. Dimroth, K.; Reichard.C, Die Colorimetrische Analyse Binarer Organischer Losungsmittelgemische Mit Hilfe Der Solvatochromie Von Pyridinium-n- Phenolbetainen. Zeitschrift Fur Analytische Chemie Fresenius, 1966, 215(5), 344-350.
22. Dimroth, K.; Reichard.C, Pyridinium-n-Phenol Betaines and Their Application for Characterization of Solvent Polarities .V. Extension of Solvent Polarity Scale by Application of Alkyl-Substituted Pyridinium-n-Phenol Betaines. Annalen Der
Chemie-Justus Liebig, 1969, 727(1), 93-105.
23. Brooker, L.G.S.; Craig, A.C.; Heseltin, D.W. ; Jenkins, P.W.; Lincoln, L.L., Color and Constitution .13. Merocyanines as Solvent Property Indicators. Journal of
the American Chemical Society, 1965, 87(11), 2443-2450.
24. Taft, R.W.; Kamlet, M.J., Solvatochromic Comparison Method .2. Alpha-Scale of Solvent Hydrogen-Bond Donor (HBD) Acidities. Journal of the American
Chemical Society, 1976, 98(10), 2886-2894.
25. Kamlet, M.J.; Abboud, J.L.; Taft, R.W., Solvatochromic Comparison Method .6. Pi-Star Scale of Solvent Polarities. Journal of the American Chemical Society,
1977, 99(18), 6027-6038.
26. Catalán, J.; Lopez, V.; Pérez, P., Solvent Dipolarity Polarizability (SPP) of Alcoholic Solvents. Liebigs Annalen, 1995(5), 793-795.
27. Catalán, J.; Diaz, C.; Lopez, V.; Pérez, P.; de Paz, J.L.G.; Rodriguez, J.G., A Generalized Solvent Basicity Scale: The Solvatochromism of 5-Nitroindoline and Its Homomorph 1-Methyl-5-Nitroindoline. Liebigs Annalen, 1996(11), 1785- 1794.
28. Catalán, J.; Diaz, C., A Generalized Solvent Acidity Scale: The Solvatochromism of o-tert-Butylstilbazolium Betaine Dye and Its Homomorph o,o'-Di-tert-Butylstilbazolium Betaine Dye. Liebigs Annalen-Recueil, 1997(9), 1941-1949.
29. Allerhand, A.; Schleyer, P.V., Nitriles and Isonitriles as Proton Acceptors in Hydrogen Bonding - Correlation of OH with Acceptor Structure. Journal of the
American Chemical Society, 1963, 85(7), 866-870.
30. Koppel, I.A.; Paju, A.I., Reakts. Sposobnost. Org. Soedin, 1974, 11, 121-136. 31. Nicolet, P.; Laurence, C.; Lucon, M., Polarity and Basicity of Solvents .3. A New
Infrared Spectroscopic Indicator of Hydrogen-Bonding Basicity. Journal of the
Chemical Society-Perkin Transactions 2, 1987(4), 483-485.
32. Persson, I.; Sandstrom, M.; Goggin, P.L., On the Coordinating Properties of Some Solvents - a Vibrational Spectroscopic Study of Mercury(II) Halides and Antimony(V) Chloride in Solution - New Concepts for Lewis Basicity Scales of Solvents. Inorganica Chimica Acta, 1987, 129(2), 183-197.
33. Taft, R.W.; Lewis, I.C.; Davis, G.T.; Fox, I.R.; Andersen, K.K.; Price, E.,
Fluorine Nuclear Magnetic Resonance Shielding in p-Substituted
Fluorobenzenes - Influence of Structure and Solvent on Resonance Effects.
Journal of the American Chemical Society, 1963, 85(20), 3146-3156.
34. Mayer, U.; Gutmann, V.; Gerger, W., Acceptor Number - Quantitative Empirical Parameter for Electrophilic Properties of Solvents. Monatshefte Fur Chemie,
1975, 106(6), 1235-1257.
35. Hildebrand, J.H., A Critique of the Theory of Solubility of Non-Electrolytes.
Chemical Reviews, 1949, 44(1), 37-45.
36. Famini, G.R.; Wilson, L.Y., Using Theoretical Descriptors in Linear Free Energy Relationships: Characterizing Several Polarity, Acid and Basicity Scales.
Journal of Physical Organic Chemistry, 1999, 12(8), 645-653.
37. Marcus, Y., The Properties of Solvents,Wiley, Chichester ; New York, 1998. 38. Bayliss, N.S.; McRae, E.G., Solvent Effects in Organic Spectra - Dipole Forces
and the Franck-Condon Principle. Journal of Physical Chemistry, 1954, 58(11), 1002-1006.
39. Reichardt, C., Solvatochromic Dyes as Solvent Polarity Indicators. Chemical
Reviews, 1994, 94(8), 2319-2358.
40. Onsager, L., Electric Moments of Molecules in Liquids. Journal of the American
Chemical Society, 1936, 58(8), 1486-1493.
41. Bayliss, N.S.; McRae, E.G., Solvent Effects in the Spectra of Acetone, Crotonaldehyde, Nitromethane and Nitrobenzene. Journal of Physical
Chemistry, 1954, 58(11), 1006-1011.
42. McRae, E.G., Theory of Solvent Effects on Molecular Electronic Spectra - Frequency Shifts. Journal of Physical Chemistry, 1957, 61(5), 562-572.
43. Ventura, M.C.M.M., Caracterização Estática e Reaccional de Misturas Binárias
Álcool/Álcool e Álcool/Alcoxiálcool, Tese de Doutoramento, Universidade de
Lisboa, Lisboa, 2001.
44. Brooker, L.G.S.; Keyes, G.H.; Heseltine, D.W., Color and Constitution .11. Anhydronium Bases of Para-Hydroxystyryl Dyes as Solvent Polarity Indicators.
Journal of the American Chemical Society, 1951, 73(11), 5350-5356.
45. Reichardt, C., Pyridinium N-Phenolate Betaine Dyes as Empirical Indicators of Solvent Polarity: Some New Findings. Pure and Applied Chemistry, 2004, 76(10), 1903-1919.
46. Laurence, C.; Nicolet, P.; Lucon, M.; Reichardt, C., Polarity and Acidity of Solvents .2. Polarity of Aromatic Solvents. Bulletin De La Societe Chimique De
France, 1987(6), 1001-1005.
47. Mente, S.R.; Maroncelli, M., Computer Simulations of the Solvatochromism of Betaine-30. Journal of Physical Chemistry B, 1999, 103(36), 7704-7719.
48. Lobaugh, J.; Rossky, P.J., Computer Simulation of the Excited State Dynamics of Betaine-30 in Acetonitrile. Journal of Physical Chemistry A, 1999, 103(47), 9432-9447.
49. Lobaugh, J.; Rossky, P.J., Solvent and Intramolecular Effects on the Absorption Spectrum of Betaine-30. Journal of Physical Chemistry A, 2000, 104(5), 899- 907.
50. Perng, B.C.; Newton, M.D.; Raineri, F.O.; Friedman, H.L., Energetics of Charge Transfer Reactions in Solvents of Dipolar and Higher Order Multipolar Character .2. Results. Journal of Chemical Physics, 1996, 104(18), 7177-7204. 51. Rauhut, G.; Clark, T.; Steinke, T., A Numerical Self-Consistent Reaction Field
(SCRF) Model for Ground and Excited-States in Nddo-Based Methods. Journal
of the American Chemical Society, 1993, 115(20), 9174-9181.
52. Ishida, T.; Rossky, P.J., Solvent Effects on Solute Electronic Structure and Properties: Theoretical Study of a Betaine Dye Molecule in Polar Solvents.
Journal of Physical Chemistry A, 2001, 105(3), 558-565.
53. Fabian, J.; Rosquete, G.A.; Montero-Cabrera, L.A., Single Configuration Interaction Study on Conjugated Betainic Chromophores Based on DFT Optimized Geometries. Journal of Molecular Structure-Theochem, 1999, 469, 163-176.
54. Zalesny, R.; Bartkowiak, W.; Styrcz, S.; Leszczynski, J., Solvent Effects on Conformationally Induced Enhancement of the Two-Photon Absorption Cross Section of a Pyridinium-n-Phenolate Betaine Dye. A Quantum Chemical Study.
Journal of Physical Chemistry A, 2002, 106(16), 4032-4037.
55. Hogiu, S.; Dreyer, J.; Pfeiffer, M.; Brzezinka, K.W.; Werncke, W., Vibrational Analysis and Excited-State Geometric Changes of Betaine-30 Derived from Raman and Infrared Spectra Combined with Ab Initio Calculations. Journal of
Raman Spectroscopy, 2000, 31(8-9), 797-803.
56. Jasien, P.G.; Weber, L.L., A Cis Study of Solvent Effects on the Electronic Absorption Spectrum of Reichardt's Dye. Journal of Molecular Structure-
57. Morley, J.O.; Padfield, J., Experimental and Computational Studies on the Solvatochromism and Thermochromism of 4-Pyridiniophenolates. Journal of the
Chemical Society-Perkin Transactions 2, 2002(10), 1698-1707.
58. Reichardt, C., Solvatochromism, Thermochromism, Piezochromism,
Halochromism, and Chiro-Solvatochromism of Pyridinium N-Phenoxide Betaine Dyes. Chemical Society Reviews, 1992, 21(3), 147-153.
59. Abboud, J.L.M.; Notario, R., Critical Compilation of Scales of Solvent Parameters. Part I. Pure, Non-Hydrogen Bond Donor Solvents - Technical Report. Pure and Applied Chemistry, 1999, 71(4), 645-718.
60. Brady, J.E.; Carr, P.W., Perfluorinated Solvents as Non-Polar Test Systems for Generalized Models of Solvatochromic Measures of Solvent Strength.
Analytical Chemistry, 1982, 54(11), 1751-1757.
61. Kamlet, M.J.; Abboud, J.L.M.; Abraham, M.H.; Taft, R.W., Linear Solvation Energy Relationships .23. A Comprehensive Collection of the Solvatochromic Parameters, Pi-Star, Alpha and Beta, and Some Methods for Simplifying the Generalized Solvatochromic Equation. Journal of Organic Chemistry, 1983, 48(17), 2877-2887.
62. Taft, R.W.; Kamlet, M.J., Linear Solvation Energy Relationships. Part 4. Correlations with and Limitations of the a Scale of Solvent Hydrogen Bond Donor Acidities. Journal of the Chemical Society-Perkin Transactions 2, 1979, 1723-1729.
63. Nicolet, P.; Laurence, C., Polarity and Basicity of Solvents .1. A Thermosolvatochromic Comparison Method. Journal of the Chemical Society-
Perkin Transactions 2, 1986(7), 1071-1079.
64. Laurence, C.; Nicolet, P.; Dalati, M.T.; Abboud, J.L.M.; Notario, R., The Empirical-Treatment of Solvent Solute Interactions - 15 Years of *. Journal of
Physical Chemistry, 1994, 98(23), 5807-5816.
65. Bekarek, V., Contribution to the Interpretation of a General Scale of Solvent Polarities. Journal of Physical Chemistry, 1981, 85(6), 722-723.
66. Yokoyama, T.; Taft, R.W.; Kamlet, M.J., Solvatochromic Comparison Method .3. Hydrogen-Bonding by Some 2-Nitroaniline Derivatives. Journal of the
American Chemical Society, 1976, 98(11), 3233-3237.
67. Krygowski, T.M.; Milczarek, E.; Wrona, P.K., An Extension of the Kamlet-Taft Basicity Scale of Solvents. Journal of the Chemical Society-Perkin Transactions
2, 1980(11), 1563-1568.
68. Laurence, C.; Nicolet, P.; Helbert, M., Polarity and Basicity of Solvents .2. Solvatochromic Hydrogen-Bonding Shifts as Basicity Parameters. Journal of the
Chemical Society-Perkin Transactions 2, 1986(7), 1081-1090.
69. Schneider, H.; Badrieh, Y.; Migron, Y.; Marcus, Y., Hydrogen-Bond Donation Properties of Organic-Solvents and Their Aqueous Mixtures from C-13 NMR Data of Pyridine-n-Oxide. Zeitschrift Fur Physikalische Chemie-International
Journal of Research in Physical Chemistry & Chemical Physics, 1992, 177,
143-156.
70. Marcus, Y., The Properties of Organic Liquids That Are Relevant to Their Use as Solvating Solvents. Chemical Society Reviews, 1993, 22(6), 409-416.
71. Wyatt, V.T.; Bush, D.; Lu, J.; Hallett, J.P.; Liotta, C.L.; Eckert, C.A., Determination of Solvatochromic Solvent Parameters for the Characterization of Gas-Expanded Liquids. Journal of Supercritical Fluids, 2005, 36(1), 16-22. 72. Catalán, J., On the Solvent Scale. Journal of Organic Chemistry, 1995, 60,
8315-8317.
73. Catalán, J., On the ET (30), *, P-Y, S', and SPP Empirical Scales as
Descriptors of Nonspecific Solvent Effects. Journal of Organic Chemistry, 1997, 62(23), 8231-8234.
74. Malavolta, L.; Oliveira, E.; Cilli, E.M.; Nakaie, C.R., Solvation of Polymers as Model for Solvent Effect Investigation: Proposition of a Novel Polarity Scale.
Tetrahedron, 2002, 58(22), 4383-4394.
75. Mancini, P.M.; Pérez, A.D.; Vottero, L.R., Nonspecific Solute-Solvent Interactions in Binary Solvent Mixtures Containing an Aprotic Hydrogen-Bond Acceptor and a Hydrogen-Bond Donor: Dipolarity/Polarizability and Refractive Index. Journal of Solution Chemistry, 2001, 30(8), 695-707.
76. Katritzky, A.R.; Tamm, T.; Wang, Y.L.; Karelson, M., A Unified Treatment of Solvent Properties. Journal of Chemical Information and Computer Sciences,
1999, 39(4), 692-698.
77. Katritzky, A.R.; Tamm, T.; Wang, Y.L.; Sild, S.; Karelson, M., QSPR Treatment of Solvent Scales. Journal of Chemical Information and Computer Sciences,
1999, 39(4), 684-691.
78. Marcus, Y., The Use of Chemical Probes for the Characterization of Solvent Mixtures .2. Aqueous Mixtures. Journal of the Chemical Society-Perkin
Transactions 2, 1994(8), 1751-1758.
79. Marcus, Y., Use of Chemical Probes for the Characterization of Solvent Mixtures .1. Completely Nonaqueous Mixtures. Journal of the Chemical
Society-Perkin Transactions 2, 1994(5), 1015-1021.
80. Mancini, P.M.; Vottero, L.R., Molecular-Microscopic Characterization of 10 Binary Solvent Mixtures Based on Solvatochromic Reference Solutes: A Comparison of Multiparametric Empirical Solvent Scales. Journal of Physical
Organic Chemistry, 2006, 19(1), 34-42.
81. Reta, M.; Cattana, R.; Silber, J.J., Kamlet-Taft's Solvatochromic Parameters for
Nonaqueous Binary Mixtures between n-Hexane and 2-Propanol,
Tetrahydrofurane, and Ethyl Acetate. Journal of Solution Chemistry, 2001, 30(3), 237-252.
82. Mancini, P.M.; Bock, A.; Adam, C.; Pérez, A.D.; Vottero, L.R., Binary Solvent Mixtures: Characterization of Molecular Environments through Multiparametric Empirical Scales. Concerns About Relationships between Kinetic Data and Microscopic Solvent Properties. Arkivoc, 2003, 373-381.
83. Bosch, E.; Rosés, M., Relationships between ET Polarity and Composition in
Binary Solvent Mixtures. Journal of the Chemical Society-Faraday
Transactions, 1992, 88(24), 3541-3546.
84. Rosés, M.; Ortega, J.; Bosch, E., Variation of ET (30) Polarity and the Kamlet-
Taft Solvatochromic Parameters with Composition in Alcohol-Alcohol Mixtures.
Journal of Solution Chemistry, 1995, 24(1), 51-63.
85. Bosch, E.; Rived, F.; Rosés, M., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures .4. Preferential Solvation of Solvatochromic Indicators in Mixtures of 2-Methylpropan-2-ol with Hexane, Benzene, Propan-2-ol, Ethanol and Methanol. Journal of the Chemical Society-
Perkin Transactions 2, 1996(10), 2177-2184.
86. Bosch, E.; Rosés, M.; Herodes, K.; Koppel, I.; Leito, I.; Koppel, I.; Taal, V., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures .2. Effect of Temperature on the ET(30) Polarity Parameter of Dipolar Hydrogen
Bond Acceptor-Hydrogen Bond Donor Mixtures. Journal of Physical Organic
Chemistry, 1996, 9(6), 403-410.
87. Ortega, J.; Ràfols, C.; Bosch, E.; Rosés, M., Solute-Solvent and Solvent- Solvent Interactions in Binary Solvent Mixtures .3. The ET(30) Polarity of Binary
Mixtures of Hydroxylic Solvents. Journal of the Chemical Society-Perkin
Transactions 2, 1996(7), 1497-1503.
88. Ràfols, C.; Rosés, M.; Bosch, E., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures .5. Preferential Solvation of Solvatochromic Indicators in Mixtures of Propan-2-ol with Hexane, Benzene,
Ethanol and Methanol. Journal of the Chemical Society-Perkin Transactions 2,
1997(2), 243-248.
89. Rosés, M.; Buhvestov, U.; Ràfols, C.; Rived, F.; Bosch, E., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures .6. A Quantitative Measurement of the Enhancement of the Water Structure in 2-Methylpropan-2- ol-Water and Propan-2-ol-Water Mixtures by Solvatochromic Indicators. Journal
of the Chemical Society-Perkin Transactions 2, 1997(7), 1341-1348.
90. Buhvestov, U.; Rived, F.; Rafóls, C.; Bosch, E.; Rosés, M., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures. Part 7. Comparison of the Enhancement of the Water Structure in Alcohol-Water Mixtures Measured by Solvatochromic Indicators. Journal of Physical Organic Chemistry, 1998, 11(3), 185-192.
91. Rosés, M.; Ràfols, C.; Ortega, J.; Bosch, E., Solute-Solvent and Solvent- Solvent Interactions in Binary Solvent Mixtures .1. A Comparison of Several Preferential Solvation Models for Describing ET(30) Polarity of Dipolar
Hydrogen-Bond Acceptor-Cosolvent Mixtures. Journal of the Chemical Society-
Perkin Transactions 2, 1995(8), 1607-1615.
92. Herodes, K.; Leito, I.; Koppel, I.; Rosés, M., Solute-Solvent and Solvent-Solvent Interactions in Binary Solvent Mixtures. Part 8. The ET(30) Polarity of Binary
Mixtures of Formamides with Hydroxylic Solvents. Journal of Physical Organic
Chemistry, 1999, 12(2), 109-115.
93. Herodes, K.; Koppel, J.; Reichardt, C.; Koppel, I.A., UV-Visible Spectroscopic Study of the Hydrophilic and Solvatoichromic-4-[2,6-Diphenyl-4-(Pyridin-4-yl) Pyridinium-1-yl]-2,6-Bis(Pyridin-3-yl)Phenolate Betaine Dye in Eight Binary Solvent Mixtures. Journal of Physical Organic Chemistry, 2003, 16(9), 626-632. 94. Herodes, K.; Leito, I.; Koppel, J.; Reichardt, C.; Koppel, I.A., UV-Vis
Spectroscopic Study of the Hydrophilic and Solvatochromic 4-[2,6-Diphenyl-4- (Pyridin-4-yl)-pyridinium-1-yl]-2,6-Bis(Pyridin-3-yl)Phenolate Betaine Dye in Aqueous Tetra-n-Butylammonium Bromide. Journal of Physical Organic
Chemistry, 2005, 18(10), 1013-1017.
95. Mancini, P.M.E.; Terenzani, A.; Gasparri, M.G.; Vottero, L.R., Determination of the Empirical Polarity Parameter ET(30) for Binary Solvent Mixtures. Journal of
Physical Organic Chemistry, 1995, 8(9), 617-625.
96. Mancini, P.M.E.; Terenzani, A.; Adam, C.; Vottero, L.R., Solvent Effects on Aromatic Nucleophilic Substitution Reactions .7. Determination of the Empirical Polarity Parameter ET(30) for Dipolar Hydrogen Bond Acceptor-Co-Solvent
(Chloroform or Dichloromethane) Mixtures. Kinetics of the Reactions of Halonitrobenzenes with Aliphatic Amines. Journal of Physical Organic
Chemistry, 1997, 10(11), 849-860.
97. Mancini, P.M.; Terenzani, A.; Adam, C.; Pérez, A.D.; Vottero, L.R., Characterization of Solvent Mixtures: Preferential Solvation of Chemical Probes in Binary Solvent Mixtures of Polar Hydrogen-Bond Acceptor Solvents with Polychlorinated Co-Solvents. Journal of Physical Organic Chemistry, 1999, 12(9), 713-724.
98. Mancini, P.M.E.; Terenzani, A.; Adam, C.; Pérez, A.; Vottero, L.R., Characterization of Solvent Mixtures. Part 8 - Preferential Solvation of Chemical Probes in Binary Solvent Systems of a Polar Aprotic Hydrogen-Bond Acceptor Solvent with Acetonitrile or Nitromethane. Solvent Effects on Aromatic Nucleophilic Substitution Reactions. Journal of Physical Organic Chemistry,
1999, 12(3), 207-220.
99. Mancini, P.M.E.; Terenzani, A.; Adam, C.; Vottero, L.R., Solvent Effects on Aromatic Nucleophilic Substitution Reactions. Part 9. Special Kinetic Synergistic Behavior in Binary Solvent Mixtures. Journal of Physical Organic Chemistry,
100. Mancini, P.M.; Adam, C.; Pérez, A.D.; Vottero, L.R., Solvatochromism in Binary Solvent Mixtures. Response Models to the Chemical Properties of Reference Probes. Journal of Physical Organic Chemistry, 2000, 13(4), 221-231.
101. Mancini, P.M.; Fortunato, G.; Adam, C.; Vottero, L.R.; Terenzani, A.J., Specific and Non-Specific Solvent Effects on Aromatic Nucleophilic Substitution. Kinetics of the Reaction of 1-Fluoro-2,6-Dinitrobenzene and Homopiperidine in Binary Solvent Mixtures. Journal of Physical Organic Chemistry, 2002, 15(5), 258-269.
102. Mancini, P.M.; Fortunato, G.G.; Vottero, L.R., Molecular Solvent/Ionic Liquid Binary Mixtures: Designing Solvents Based on the Determination of Their Microscopic Properties. Physics and Chemistry of Liquids, 2004, 42(6), 625- 632.
103. Marcus, Y., Solvent Mixtures : Properties and Selective Solvation, Marcel Dekker: New York, 2002.
104. Elias, H.; Gumbel, G.; Neitzel, S.; Volz, H., Polarity of Binary Solvent Mixtures - Determination of ET(30)-Values and Correlation with Kinetic Solvent Effects.
Fresenius Zeitschrift Fur Analytische Chemie, 1981, 306(4), 240-244.
105. Koppel, I.A.; Koppel, J.B., ET Parameters of Some Binary-Mixtures of
Hydroxylic and Aprotic-Solvents. Organic Reactivity, 1983, 20(4), 547-560. 106. da Silva, D.C.; Ricken, I.; Silva, M.A.D.; Machado, V.G., Solute-Solvent and
Solvent-Solvent Interactions in the Preferential Solvation of Brooker's Merocyanine in Binary Solvent Mixtures. Journal of Physical Organic Chemistry,
2002, 15(7), 420-427.
107. Silva, M.A.D.; da Silva, D.C.; Machado, V.G.; Longhinotti, E.; Frescura, V.L.A., Preferential Solvation of a Hydrophobic Probe in Binary Mixtures Comprised of a Nonprotic and a Hydroxylic Solvent: A View of Solute-Solvent and Solvent- Solvent Interactions. Journal of Physical Chemistry A, 2002, 106(37), 8820- 8826.
108. Mancini, P.M.; Pérez, A.D.; Vottero, L.R., Grouping of Hydrogen-Bond Ability of Pure Solvents and Their Binary Mixtures Based on the Similarity of Their Microscopic Properties. Physics and Chemistry of Liquids, 2003, 41(1), 45-54. 109. Bevilaqua, T.; da Silva, D.C.; Machado, V.G., Preferential Solvation of Brooker's
Merocyanine in Binary Solvent Mixtures Composed of Formamides and Hydroxylic Solvents. Spectrochimica Acta Part A-Molecular and Biomolecular
Spectroscopy, 2004, 60(4), 951-958.
110. Mehranpour, A.M.; Hashemnia, S., Solvatochromism in Binary Solvent Mixtures by Means of a Penta-tert-Butyl Pyridinium n-Phenolate Betaine Dye. Journal of