Carboxylic acids formic

Figure 3-6. Fugacity coefficients for saturated mixtures containing two carboxylic acids formic acid (1) and acetic...

Acids. (A) Carboxylic Acids. Formic, acetic (and higher ali ... 

The name of a carboxylic acid always ends in -ic, and the name of the anion ends in -ate. Figure 17-9 shows three simple carboxylic acids formic acid ( K = 1.8 x 10 ), acetic acid ( K — 1.8 X 10 ), and benzoic acid ( Ta = 6.4 X 10 ). HCO2 is formate, CH3 CO2 is acetate, and Cg H5 CO2 is benzoate. Examples and treat benzoic acid quantitatively. 

Biomass pyrolysis in the presence of a catalyst, in situ, is considered as one of the options to overcome the problem characteristics of bio-oil mentioned above. Selective removal, by decarboxylation, of carboxylic acids (formic, acetic acids)... 

In short, while the focus has been primarily on sulfuric and nitric acids as a source of acid deposition, it is clear that organic acids can also contribute significantly. The gas-phase concentrations of the simplest carboxylic acids, formic acid and acetic acid, are relatively high even in remote regions, of the order of a ppb. Both natural and anthropogenic sources have been... 

Carboxylic acids The smallest carboxylic acid, formic acid, can be measured using infrared spectroscopy (Table 11.2), since it has characteristic absorption bands. As discussed earlier and seen in Fig. 11.33b, mass spectrometry with chemical ionization using SiF5 also revealed HCOOH in an indoor environment (Huey et al., 1998). However, since the sensitivity in these initial studies was about two orders of magnitude less than that for HN03, the detection limit may be about the same as that for FTIR and TDLS. Formic and acetic acids have been monitored continuously from aircraft (Chapman et al., 1995) and their surface flux determined by eddy correlation (Shaw et al., 1998) using atmospheric pressure ionization mass spectrometry. Detection limits are about 30 ppt. 

The Hammett correlation for substituted carboxylic acids is demonstrated in Figure 5.26. The Hammett constant om fails for aliphatic compounds, and the derived constant o must be used to predict accurate Hammett correlations. The least-substituted carboxylic acid, formic acid, was used as the reference compound. The Hammett correlation for substituted carboxylic acids (CAs) demonstrates that the CAs substituted by electron-withdrawing substituents, such as Cl, oxidize the fastest. CAs substituted by electron-donating groups, such as CH3 and NH2, oxidize more slowly than those substituted by electron-withdrawing substituents. The reaction pathway for substituted carboxylic acids is shown in Figure 5.27. These trends are different for phenols and alkanes, because the reaction site is at the election pair located at the oxygen atom. 

R,7R)-7-[2-[2-(2-Chloroacetamido)-4-thiazolyl]-2-(methoxyimino) acetamido]-8-oxo-3-[[(l,4,5,6-tetrahydro-4-methyl-5,6-dioxo-as-triazin-3-yl)thio]methyl]-5-thia-l-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid Formic acid... 

Carboxylic acids formic, acetic, propionic, butyric, pentanoic, hexanoic, 10-15 glycolic, (hydroxy acetic))... 

Different organic compounds have been investigated at BDD and BDD/Ir02 electrodes by cyclic voltammetry and preparative electrolysis. As model organic compounds, simple alcohols (methanol, ethanol, n-propanol, isopropanol, and ter-butanol) and simple carboxylic acids (formic acid, oxalic acid, and maleic acid) have been investigated. Two mechanisms can be distinguished for the organics oxidation ... 

The+utility of carboxylic acids (formic, acetic), which also form Pu complexes sparsely soluble in TBP solutions, was investigated by Germain (22) and McKay (23). The results were not encouraging. 

Figure 12 Crematogaster ants make the simplest carboxylic acid, formic acid. Notice the structure of the —COOH group.

Decarboxylation is, of course, easiest when the carboxyl group is loosened by the influence of neighboring groups. Malonic acid18 and suitable substitution products73 can, after deuteration, be readily converted into deuterated acetic acid and its derivatives. Moreover, the simplest carboxylic acid, formic acid, has been obtained labeled in this way 74,75... 

H-Fluoretie-1-carboxylic acid Formic acid H-COOH... 

D-a-t-Butoxycarbonylamino-a-(p-hydroxyphenyl)acetamido] -3-(1,2,3-triazol-5-ylthiomethyl)-3-cephem-4-carboxylic acid Formic acid... 

Aliphatic carboxylic acids Formic, ethanoic, dimethylethanoic, propanoic, oxalic adds... 

Acetic acid is commonly recovered from dilute aqueous mixtures using liquid-liquid extraction. A typical flowsheet is shown in Fig. 7.8-8 where liquid-liquid extraction is combined with azeotropic distillation for solvent regeneration. A variety of solvents may be used including acetates, ethers, alcohols, ketones, and chlorinated hydrocarbons. In addition, several excellent reviews on acid recovery by liquid-liquid extraction are available. Recently, Siebenhofer and Marr presented data on the extraction of several carboxylic acids (formic, acetic, propionic, and butyric) using tertiary amines. Kawano and Kusano present data on acetic acid extraction rates using long-chain alkylamines. 

The first four aliphatic carboxylic acids (formic, acetic, propanoic, and butanoic acids) are infinitely soluble in water because the hydrophilic character of the carboxyl group more than counterbalances the hydrophobic character of the hydrocarbon chain. As the size of the hydrocarbon chain increases relative to the size of the carboxyl group, water solubility decreases. The solubility of hexanoic acid in water is 1.0 g/100 g water that of decanoic acid is only 0.2 g/100 g water. 

Acetic acid is a carboxylic acid. Formic acid is the lowest carboxylic acid, and it contains only 1 C atom per molecule. What is its formula ... 

Besides synthesis of pharmaceutical co-crystals, mechanosynthesis has been successfully applied to the synthesis of pharmaceutical salts. Trask et al. have demonstrated mechanochemical screening for pharmaceutical salts by grinding the model API molecules trimethoprim and pyrimethamine with seven pharmaceutically acceptable carboxylic acids formic, acetic, maleic, fumaric, succinic, glutaric and salicylic. The results of screening experiments (Table 8.2) demonstrate that LAG is more versatile than neat grinding in screening for pharmaceutical salts. More importantly, the application of mechanochemical techniques not only led to the formation of already reported salt forms but also enabled the discovery of 14 new salt forms. 

Formic acid and acetic acid are the two most important carboxylic acids. Formic acid is a source of irritation in the bites of ants and other insects or in the scratch of nettles. A liquid with a sharp, irritating odor, formic acid is used in manufacturing esters, salts, and plastics. Acetic acid is present in a concentration of about 5% in vinegar and is responsible for its odor and taste. Acetic acid is among the least expensive organic acids, and is therefore a raw material in many commercial processes that require a carboxylic acid. Sodium acetate is one of several common salts of carboxylic acids. It is used to control the acidity of chemical processes and in preparing soaps and pharmaceutical agents. 

For the simplest carboxylic acid, formic acid, this latter step leads to H + CO2. The reaction of S04 with acetate, however, leads predominately to decarboxylation 193]. Rate constants for the reactions of acetate 196] and several halo-genated acetates [97] have been measured, Substitution of a single chlorine or fluorine for a hydrogen makes little difference in the rate constant. Substitution of two chlorines reduces the rate constant by a factor of two, while two fluorines reduce it by a factor of 50. Three fluorines lower the rate constant by almost 3(X) the effect of three chlorines is significant, but uncertain. 

Carboxylic acids formic acid, acetic acid, propionic add, butyric acid, valeric acid, caproic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic add, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic add, hexadecanoic add, heptadecanoic acid, octadecanoic acid, benzoic acid, lactic acid... 

Depending on the substituent carboxylic acids RCOOH may form rather complicated crystal structures 80,8l. The simplest carboxylic acids, formic and acetic acid, form catemeric chains in the... 

Water-soluble carboxylic acids have been found in oil-field formation waters from around the world (Carothers and Kharaka 1978 Surdam et al. 1984 Hanor and Workman 1986 Fisher 1987 Means and Hubbard 1987 MacGowan and Surdam 1988, 1990 Barth et al. 1990 Fisher and Boles 1990 Lundegard and Kharaka, Chap. 3, this Vol.) with total concentrations reaching up to 10000 ppm (Surdam et al. 1984). Total concentrations and abundances of individual species vary widely and only a few of the simple monofunctional and difunctional groups have been identified in each study. Typically, monofunctional carboxylic acids (formic, acetic, propionic. 

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