Aromatic solutes

Sun-Chen examined tracer diffusion data of aromatic solutes in alcohols up to the supercritical range and found their data correlated with average deviations of 5 percent and a maximum deviation of 17 percent for their rather hmited set of data. 

In alicyclic hydrocarbon solvents with aromatic solutes, energy transfer (vide infra) is unimportant and probably all excited solute states are formed on neutralization of solute cations with solute anions, which are formed in the first place by charge migration and scavenging in competition with electron solvent-cation recombination. The yields of naphthalene singlet and triplet excited states at 10 mM concentration solution are comparable and increase in the order cyclopentane, cyclohexane, cyclooctane, and decalin as solvents. Further, the yields of these... 

Kamlet, M. J., Doherty, R. M., Abraham, M. H., Carr, P. W., Doherty, R. F., Raft, R. W. (1987) Linear solvation energy relationships. Important differences between aqueous solubility relationships for aliphatic and aromatic solutes. J. Phys. Chem. 91, 1996-2004. 

Tsonopoulos, C., Prausnitz, J. M. (1971) Activity coefficients of aromatic solutes in dilute aqueous solutions, hid. Eng. Chem. Fundam. 10, 593-600. 

The linear dependence between the activation energy of decomposition of the azocompounds RN2R and the BDE of the R—H bond (D(R—H)) was established [3], The rate constants of the decomposition of azo-compounds in the gas phase and hydrocarbon solvents have close values. The mean value of the rate constant of AIBN decomposition in hydrocarbon and aromatic solutions was recommended to bekd= 1015 x exp(— 127.5/RT) s-1 [2], The values of the activation energies and the rate constants of the decomposition of azo-compounds in the gas and liquid phases can be found in the Handbook of Radical Initiators [4],... 

Campbell, J.R., Luthy, R.G., and Carrondo, M.J.T. Measurement and prediction of distribution coefficients for wastewater aromatic solutes, Environ. Sci. Technol., 17(10) 582-590, 1983. 

For the solubility of aromatic solutes in water at 25°C, a different equation holds ... 

When polychlorinated biphenyls and polycyclic aromatic hydrocarbons are included with other aromatic solutes, the slightly modified equation... 

RW Taft, MH Abraham, GR Famini, RM Doherty, JL Abboud, MJ Kamlet. Solubility properties in polymers and biological media 5 an analysis of the physicochemical properties which influence octanol-water partition coefficients of aliphatic and aromatic solutes. J. Pharm. Sci. 74 807-814 (1985). 

Class (1) reactions were observed in all four cycloalkanes. The highest rate constants were observed for reactions of cyclohexane hole with low-IP aromatic solutes, (3-4.5) x 10" sec at 25°C [75]. In these irreversible reactions, a solute radical cation is generated. Class (2) reactions were observed for reactants 1,1-dimethylcyclo-pentane, trans-l, 2-dimethylcyclopentane, and 2,3-dimethyl-pentane in cyclohexane [74], trans-dtcaXm, bicyclohexyl, and Ao-propylcyclohexane in methylcyclohexane [69], and benzene in cis-... 

Aromatic solutes can photosensitize the homolysis of C—H bonds in hydrocarbon solvents at low temperatures in rigid media.222,241,242 The reaction is biphotonic in rigid media where triplet lifetimes are sufficiently long, intense irradiation can populate second excited triplets by T-T absorption. The second excited triplets of several aromatic compounds apparently can transfer their energy to solvent molecules and cause bond cleavage. 

CTTS transitions, in which the oriented solvent participates are absent in the spectrum of the aromatic solutes but the lifetime of the excited state, as shown by the existence of fluorescence is longer, probably 10 9 sec. During this extended lifetime, sufficient reorganization of the solvent may occur to enable the excited electron to be trapped, and to allow for the first relative diffusive displacement of the gemini, which is necessary for the observed kinetics to develop. The temperature ef-... 

Gadelle et al. (1995) investigated the solubilization of various aromatic solutes irbfftRSS-b-PEO (ABA)/PPO-bPEO-bPPO (BAB) triblock copolymers. According to the experimental results, they indicated two different solubilization processes. To understand better the mechanism for solubilization in the polymeric surfactant solutions, it was postulated that (1) the addition of apolar solutes promotes micellization of the polymeric surfactant molecules, (2) the central core of the polymeric micelles contains some water molecules, and (3) solubilization is initially a replacement process in which water molecules are displaced from the micellar core bythesolubilizate. Adetailed discussion of the solubilization process can be found in the next section and the pharmaceutical application section of this chapter. 

Gadelle, F., W. J. Koros, and R. S. Schechter, 1995. Solubilization of aromatic solutes in block copolymers. Macromolecule 8 4883-4892. 

Campbell, J.R. and R.G. Luthy. 1985. Prediction of Aromatic Solute Partition Coefficients Using the UNIFAC Group Contribution Model. Environ. Sci. Technol. 19 980-985. 

Fu, K., and R.G. Luthy. 1986. Effect of organic solvent on sorption of aromatic solutes onto soil. Journal of Environmental Engineering 112(2) 346-366. 

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