Solubility of Organic Compounds in Water

Divide the saturated solution of n-butyl alcohol in water into three approximately equal parts. Treat these respectively with about 2-5 g. of sodium chloride, potassium carbonate and sodium hydroxide, and shake each until the soli have dissolved. Observe the effect of these compounds upon the solubility of n-butanol in water. These results illustrate the phenomenon of salting out of organic compounds, t.e., the decrease of solubility of organic compounds in water when the solution is saturated with an inorganic compound. The alcohol layer which separates is actually a saturated solution of water in n-butyl alcohol. 

Metal ions in aqueous solution exist as complexes with water. The solubility of organic compounds in water depends primarily on their polarity and their ability to form hydrogen bonds with water. Organic compounds with a large part of polar components such as acetic acid, dissolve in water without limit. In such cases, the polar part dominates. By contrast, soaps and detergents have a polar end attached to a relatively large nonpolar part of the molecule. They have limited solubility and the molecules tend to coalesce to form micelles. 

Lyubartsev, A.P., Jacobsson, S.P., Sundholm, G and Laaksonen, A. Solubility of organic compounds in water/octanol systems. An expanded ensemble molecular dynamics simulation study of log Pparameters, J. Phys. Chem. B, 105(32) 7775-7782, 2001. 

However, it may also be possible that the buffer negatively influences the solubility of the drug and other excipients. Buffer salts can either increase or decrease the solubility of organic compounds in water. The effect depends on a combination of the polarity of the solute and of the salt. Nonpolar solutes are solubilized (salted in) by less polar organic salts and are desolubilized (salted out) by polar salts. Conversely, polar solutes are salted in by polar salts and salted out by organic salts. It was shown that for a semipolar solute such as ampicillin, strong electrolytes... 

Two methods have been utilized to circumvent the low solubility of organic compounds in water. The first is use of emulsifying ngem.--. such aa common household detergents, from which the product ran bo separated readily by steam-distillation sw.yot.iss The second is use of a suitable mutual solvent, e.g. acetone,1 fort-butanol,741-777 or dioxan.80- i . m>, 4ei, ess. iocs. i 7s. i4 e, ims, ms.m ... 

An emulsifier is a molecule that possesses both polar and nonpolar moieties, i.e., it is amphiphilic. In very dilute water solutions, emulsifiers dissolve and exist as monomers, but when their concentration exceeds a certain minimum, the so-called critical micelle concentration (CMC), they associate spontaneously to form aggregates - micelles. Micelles are responsible for many of the processes such as enhancement of the solubility of organic compounds in water, catalysis of many reactions, alteration of reaction pathways, rates and equilibria, reaction loci for the production of polymers, etc. 

Solubilities in two non-miscible liquids dissolved in a consolute liquid, with a solid also in solution, were considered by Bancroft and Bell they cover such cases as potassium carbonate in alcohol and water separated into two layers. A theory of solubility of organic compounds in water was given by... 

Suzuki, T., Ohtaguchi, K. and Koide, K. (1992b). Computer-Aided Prediction of Solubilities of Organic Compounds in Water. J.Chem.Eng.Jpn., 25,729-734. 

Hydrotropic agents, such as sodium xylenesulfonate increase the solubility of organic compounds in water. Dow sells a hydrotropic disulfonate diphenyl ether as Dowfax 2A1 (8.37). 

As mentioned in Section 4.1, CB[n] hosts have been used to increase the solubility of organic compounds in water, in order to break them down through chemical reaction [55,94—96]. Karcher et al. studied the potential applicability of CB[6] nanoreactors to extract reactive dyes from wastewater [55], particularly in the presence of alkali and alkaline-earth metal cations, and then destroy them using ozonolysis [116]. They found that while oxidation through reaction with ozone was enhanced by the CB[6] nanoreactors, the... 

Although chemical transformations in aqueous solutions are known, in general, the poor solubility of organic compounds in water avoids the use of aqueous solvents in chemical reactions. Some early examples of reactions in aqueous medium can be traced back to the Wohler s urea synthesis in 1828 [70] and the Baeyer-Drewsen indigo synthesis in 1882 [71], MCR protocols, as already stated, are very important for developing new pharmaceuticals and libraries of medicinal scaffolds. However, few examples for MCRs in water as the solvent have been reported in the literature. In this section, we will discuss some selected MCRs in water ... 

For the logarithm of the molar solubility of organic compounds in water, S, instead of the initial regression ... 

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