Solvatochromic studies

It should be mentioned that water and 1-octanol are not completely immiscible. The solubility of water in 1-octanol is = 2.46 mol/L at 25 °C [=mole fraction x(H20) = 0.289], and that of 1-octanol in water is = 3.29 10 mol/L [=x( 1-octanol) = 9.32-10 " ] [148]. In the application of Aio/w values, it is tacitly assumed that the solvent properties of 1-octanol saturated with water are not different from those of neat 1-octanol. In practice, the presence of water in 1-octanol should increase the concentration of polar and H-bonding solutes and decrease the concentration of nonpolar solutes. However, solvatochromic studies by Carr et al. have shown that the water saturation of 1-octanol has only a very small effect on the properties of bulk 1-octanol. The water is almost completely associated with the hydroxy group of 1-octanol and scarcely affects the properties of this medium [148]. 

Miceller,Micelle interactions. Solvatochromic studies have... 

More recent solvatochromic studies [14-20] employ specialised dyes reflecting specific microscopic molecular interactions. For example, the Abboud-Kamlet-Taft solvent parameters [21-23] a, 3 and n give information on hydrogen bond donor and acceptor properties and the polarisability of a compound, respectively. For ionic liquids with [C4mim]-cations, the following order of [3- values was estab-... 

Boggetti H, Anunziata ID, Cattana R, SUber 11 (1994) Solvatochromic study on nitroanihnes. Preferential solvation vs dielectric enrichment in binary solvent mixtures. Spectrochim Acta A Mol Spectrosc 50 719-726... 

Valenta, J. N., Sun, L., Ren, Y, and Weber, S. G, Solvatochromic study of poly(vinyl chloride) plasticizers and their solutions in chloroform application to phenobarbital partitioning and molecular recognition of phenobarbital. Analytical Chemistry, 69, 3490, 1997. 

Figure 6.3 Solvatochromic studies of poly(l,4-(2,3-di-(5)-2-methylbutoxyphenylene)-a/f-2,5-furan) in different solvents (a) UV-vis measurements (b) CD measurements, reported in Reference [53b]. (Reproduced by permission of the American Chemical Society. Copyright 2002. Reprinted from Reference [53b]).

Knoevenagel reactions can be carried out at ambient temperature using an ionic liquid, dimethylethanolammonium acetate it features wide substrate tolerance, and ease of workup and reuse. " ° Its catalytic effect has been demonstrated by a solvatochromic study which identifies dual functions the cation hydrogen-bonds to the aldehyde, and the anion acts as acceptor to the active methylene substrate, facilitating the formation of carbanion. 

KP Hafner, FLL PouiUot, CL Liotta, CA Eckert. Solvatochromic study of basic cosolvents in supercritical ethane. AIChE J 43 847, 1997. 

This sensitivity of the handedness of chiral substituted polythiophenes to the conditions under which micro-aggregation occurs has been further confirmed in detailed thermochromic and solvatochromic studies by Meijer et on 23 and the related chiral polythiophenes 32 and 25. Polymers... 

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