Carboxylic acid derivatives solubility

Even higher Xe-binding constants from aqueous solutions have been reported for the water-soluble, carboxylic acid-derived 23 and 24. ... 

C, which decomposes when heated above the melting point. Its solubility at 25°C in g/100 g solvent is water. 111 methanol, 5 ethanol, 1.4 acetone, 0.04 and carbon tetrachloride, 0.004. Because its carbon—fluorine bond is unreactive under most conditions, this salt can be converted by standard procedures to typical carboxylic acid derivatives such as fluoroacetyl esters (11,12), fluoroacetyl chloride [359-06-8] (13), fluoroacetamide (14), or fluoroacetonitrile [503-20-8] (14). 

A carboxylate derivative of a fully aromatic, water-soluble, hyperbranched polyphenylene is considered as a unimolecular micelle due to its ability to complex and solubilize non-polar guest molecules [23]. The carboxylic acid derivative of hyperbranched polyphenylene polymer (HBP) (My,=5750-7077, Mn=3810-3910) consists of 40-60 phenyl units that branch outward from a central point forming a roughly spherical molecule with carboxylates on the outer surface. The free acid form of HBP was suspended in distilled water and dissolved by adding a minimum quantity of NaOH. The solution was adjusted to pH 6.2 with aqueous HCl. Calcium carbonate crystals were growth from supersaturated calcium hydrogencarbonate solution at room temperature. HBP gave... 

One of the more difficult partial reductions to accomplish is the conversion of a carboxylic acid derivative to an aldehyde without over-reduction to the alcohol. Aldehydes are inherently more reactive than acids or esters so the challenge is to stop the reduction at the aldehyde stage. Several approaches have been used to achieve this objective. One is to replace some of the hydrogens in a group III hydride with more bulky groups, thus modifying reactivity by steric factors. Lithium tr i - / - b u to x y a I u m i n u m hydride is an example of this approach.42 Sodium tri-t-butoxyaluminum hydride can also be used to reduce acyl chlorides to aldehydes without over-reduction to the alcohol.43 The excellent solubility of sodium bis(2-methoxyethoxy)aluminum hydride makes it a useful reagent for selective... 

In vertebrates, free fatty acids (unesterified fatty acids, with a free carboxylate group) circulate in the blood bound noncovalently to a protein carrier, serum albumin. However, fatty acids are present in blood plasma mostly as carboxylic acid derivatives such as esters or amides. Lacking the charged carboxylate group, these fatty acid derivatives are generally even less soluble in water than are the free fatty acids. 

Complex or soluble neutral metal hydrides are usually employed for the reduction of carboxylic acid derivatives to alcohols or amines. The standard reagents for the most important transformations are shown in Table 17.6. For completeness, various reagents also are listed for the reduction of carboxylic acid derivatives to aldehydes. The latter mode of reduction was discussed in Section 6.5.2. 

Fullerenes Very tiny balls consisting of 60 carbon atoms with diameter of 0.7 nm Water-soluble carboxylic acid Cm derivatives acting as antimicrobials, being linked to a variety of active molecules 25, 38, 39... 

Straight-chain alkyl carboxylic acids derived from petroleum that also have a terminal cyclohexyl or cyclopentyl group are known as naphthenic acids. They form complexes, presumably polymeric, with many transition metals, and these compounds are freely soluble in petroleum. Copper naphthenates are used as fungicides, aluminum naphthenate was used as a gelling agent in napalm, and cobalt naphthenates are used in paints. 

Positive Photoresists. Positive resists are entirely different from negative resists. For the purposes of this discussion we restrict ourselves to visible-light-sensitive materials. Typically, these materials are mixtures of low-molecular-weight phenol-formaldehyde polymers and derivatives of naphtho-1,2-quinone diazide, the photosensitive component. The former is soluble in aqueous alkali, but the presence of the latter, a hydrophobic species, inhibits attack of this developer on the film. On irradiation the "sensitizer" is converted to a ketene, which, after reaction with water, forms a base-soluble carboxylic acid. Thus the irradiated part of the film is rendered soluble in the developer and it can be removed selectively. The important feature of this system is that the unirradiated areas are not swollen by the developer and the resolution of this material is quite high. It is possible to prepare gratings having several... 

Carboxylic acid derivatives are soluble in organic solvents regardless of size. 

Most carboxylic acid derivatives having < 5 C s are H2O soluble because they can hydrogen bond with H2O (Section 3.4C). 

The ketone groups of aldosterone, corticosterone, and cortisol were derivatized with p-hydrazinobenzoic acid. The resulting carboxylic acid derivatives could be linked to BSA with water-soluble carbodiimide. Aldehydes can be conjugated to proteins directly by Schiff base formation followed by stabilization of the bond by reduction with sodium borohy-dride. Pyridoxal and pyridoxal phosphate are examples of haptens conjugated in this manner. ... 

Ketorolac is, hke several other NSAIDs, promoted as a non-narcotic analgesic. This is merely a marketing ploy, which does not reflect any special characteristics, except that it is one of many NSAIDs that can be given parent-erally. A pyrrolizine carboxylic acid derivative, it is strnc-turally and pharmacologically related to tolmetin, zomepirac, and indometacin. The trometamol salt of ketorolac enhances its solubility and allows parenteral administration single intramuscular injections are better tolerated than morphine. 

Aspirin is a carboxylic acid derivative, while paracetamol is a substituted phenol. Addition of a strong base (e.g. sodium hydroxide) would result in ionisation of both acids (and some hydrolysis of the aspirin). To separate the acids successfully, a discriminating base must therefore be used, which is formed from an acid intermediate in strength between carboxylic acids and phenols. Such an acid is carbonic acid (H2COs) and addition of sodium bicarbonate solution will result in ionisation of the aspirin as the sodium salt. This salt will be water soluble and may be removed in the lower phase. Addition of fresh organic solvent and dilute hydrochloric acid solution will yield aspirin as free acid. 

Carboxylic acid derivatives are soluble in solvents such as ethers, chlorinated alkanes, and aromatic hydrocarbons. Like alcohols and ethers, carbonyl compounds with fewer than four carbons are soluble in water. 

Thioamides have become a ubiquitous but important class of compounds - much like ordinary organic compounds such as aldehydes, ketones, and carboxylic acid derivatives - and extensive studies into their syntheses and reactions have been carried out in recent years. When an oxygen atom in an amide is replaced with a sulfur atom, the compounds become less polar and more soluble in various organic solvents. They are reactive but still stable enough to be handled in air. Therefore, a tremendous number of studies have been made into their fundamental properties, biological aspects, and broad applicabilities. Theoretical studies into the rotational barriers that exist in the thioformamides 4 and the thioacetamides 5 have also been made (for example [1]). 

X.-M. Liu, C. He and J. Huang, A water-soluble non-aggregating fluorescent octa-carboxylic acid derived from tetraphenyhnethane synthesis and optical properties. Tetrahedron Lett., 45, 6173-6177 (2004). 

---