Carboxylic acids benzoic

Methyl groups attached to benzene rings can be reacted with oxygen to produce aromatic carboxylic acids. Benzoic acid, the parent aromatic acid, finds wide use as a food preservative and in metal corrosion inhibitors. Aspirin and saccharin are derivatives of benzoic acid. 

The red part of this ester is derived from the alcohol [propanol], and the blue part from the carboxylic acid [benzoic acid]. Be careful to correctly identify which part of each ester comes from the acid and which from the alcohol. Note that propyl and benzoate are separate words.)... 

The most important of the aromatic carboxylic acids, benzoic acid and the... 

Problem 26.12 In contrast to most carboxylic acids (benzoic acid, say) 2,4,6-tri-nitrobenzoic acid is decarboxylated extremely easily by simply boiling it in aqueous acid. How do you account for this ... 

Aromatic carboxylic acids (benzoic acid [2902], aspirin [102]) have a moderately characteristic chromophore the absorption maxima are around 273 3 nm and 227 3 nm and can only be seen as an indication of identity together. Ionisation in NaOH reduces the absorption compared with the solution in methanol. Other chromophores present at the same point usually cover the aromatic carboxyl absorption. 

Formic acid, pK 3.75, serves as the reference carboxylic acid. Benzoic acid is weaker because the phenyl group is electron-donating by resonance, stabilizing the protonated form. Methyl substituents are known to be electron-donating by induction, strengthening the electron-donating effect, making the meta- and para-substituted acids weaker than benzoic acid. 

Aminobenzoic acid m-Aminobenzoic acid Aniline-3-carboxylic acid Benzoic acid, 3-amino- Benzoic acid, m-amino- BRN 0471603 3-Carboxyaniline m-Carboxyaniline EINECS 202-724-4 MABA NSC 16012. Used in chemical synthesis and manufacturing. Crystals mp = 173" d25 = 1.151 = 219, 317 nm (s = 25800, 1930, MeOH) ... 

IX IX, let Supplement IX, 2nd Supplement 1926 891-1050 Carboxylic Acids. Benzoic acid, 92. Cinnamic acid, 672. 

Aromatic carboxylic acids Benzoic, 4-aminobenzoic, phthalic, salicyclic, m- and p-hydioxybenzoic, chlorohydioxybenzoic acids... 

The test identifies the substance to be examined as either a benzoate salt or a substance that yields benzoic acid upon chemical manipulation. Reference to benzoates is at present made in only three monographs describing benzoic acid (Figure 3.11.1) itself, ifs sodium salt, and benzoyl peroxide, which upon basic hydrolysis yields two benzoic acid equivalents. Being a carboxylic acid, benzoic acid has a water solubility that depends strongly on the pH of the solution. The free acid is sparingly soluble in cold water but significantly more soluble in hot water. It is soluble in alcohol and ether. All common benzoate salts except the salts of silver and basic iron(III) are water soluble. 

As a rule, alkenes do not react with 78-80 unless there is another reagent present—specifically, a transition metal. This reaction will not be discussed further. In sharp contrast, peroxycarboxylic acids such as 81 react directly with alkenes. Peroxycarboxylic acids 81 are named by adding the term peroxy to the name of the carboxylic acid (see Chapter 5, Section 5.9.3 and Chapter 16, Section 16.4). Using the common names, the peroxy analog of formic acid is peroxyformic acid (82), and others include peroxyacetic acid (83), peroxytrifiuo-roacetic acid (84), peroxybenzoic acid (85), and me a-chloroperoxybenzoic acid (abbreviated mCPBA, 86). Peroxycarboxylic acid 85 is a derivative of the aromatic carboxylic acid benzoic acid (PhCOOH), and the carboxylic acid precursor to 86 is clearly another aromatic carboxylic acid. (The nomenclature and structural features of benzoic acid and other aromatic carboxylic acid derivatives will be discussed in detail in Chapter 21, Section 21.2.) The salient feature of peroxyacids 82-86 is the presence of the electrophihc oxygen atom mentioned previously, which will react with an alkene. 

Carboxylic acids Benzoic acid/ Ca-montmorillonite Hydrogen bonding/ water bridges Yariv et al. (260)... 

Three aromatic carboxylic acids, benzoic add (Arl), phenylacetic acid (Ar2), and 4-methoxyphenylacetic acid were selected as guests to probe the depth of penetration in host 1, and, as well, two aliphatic carboxylic acid guests, cydo-hexylacetic acid (All), and l-adamantanecarboxyHc acid (A12), were also used to further study the importance of hydrophobic effects in the molecular recognition process with host 1. According to their plQ values, all of these carboxylic adds existed in the anionic form at pH 7 [4a, b]. The CICS values of the three guests, Arl, Ar2, and 4-methoxyphenylacetic acid, by host 1 are presented in a similar fashion as described above for the substituted aromatic carboxylic acids (Fig. 10.6). 

A considerable number of laboratories investigating this material for wastewater treatment and the number of related publications have rapidly increased during the last two decades. Many papers have demonstrated that BDD anodes allow complete mineralizations up to near 100 % current efficiency of a large number of organic pollutants, such as carboxylic acids, benzoic acid, cyanides, cresols, herbicides, drugs, naphthol, phenolic compotmds, polyhydroxybenzenes, polyacrylates, surfactants, and real wastewaters. The experimental conditions and some results of the most relevant research on this electrode material are summarized in Table 1 (results adapted from references [2-5, 7]). 

Carboxylic Acid Benzoic acid anhydride C14H10O3 93-97-0 230 231 —... 

In a related study [35], surface complexation of colloidal Ti02 by aryl carboxylic acids (benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid and catechol) has been found to obey the Langmuir Isotherm. Surface chelation is accompanied by a decrease of the point of zero zeta potential (PZZP) and enhanced electron transfer rates from the conduction band and acceptors in solution. The enhanced electron transfer rates observed upon surface chelation (of cobaltocenium dicarboxylate, phenylfluorene and aryl carboxylic acids) suggest that trapping of electrons by Ti(IV) surface states (equation 3) can take place efficiently and removal of such traps by complexation improves the overall performance of the system. 

Methanol (8-11) is a member of the homologous series of saturated aliphatic alcohols found in plants in the form of various esters, most often in pectins and esters of aromatic carboxylic acids (benzoic, salicylic, cinnamic and others). Free methanol results mainly by hydrolysis of pectin catalysed by plant pectin esterases therefore, it occurs regularly in small amounts as a component of aU natural fruit juices and is present in larger amounts in wines and fruit distillates. 

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