What Are Carboxylic Acids

The functional group of a carboxylic acid is a carboxyl group, so named because it is made up of a carbonyl group and a hydroxyl group (Section 1.7D). Following is a Lewis structure of the carboxyl group, as well as two alternative representations of it  

The general formula of an aliphatic carboxylic acid is RCOOH that of an aromatic carboxylic acid is ArCOOH. 

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What are carboxylic acids Briefly discuss their properties and the system of naming. 

What are carboxylic acids Identify the group that is present in carboxylic acids. Write a Lewis diagram for the group and describe the geometry around all central atoms within the group. 

What are fatty acids Fatty acids are carboxylic acids that may or may not have double bonds in their hydrocarbon portion. 

What Are the Acid-Base Properties of Carboxylic Acids ... 

How are carboxylic acids synthesized Give an example of an organic acid and the molecule from which it is synthesized. What type of reaction is this ... 

Solvent Effects on the Rate of Substitution by the S 2 Mechanism Polar solvents are required m typical bimolecular substitutions because ionic substances such as the sodium and potassium salts cited earlier m Table 8 1 are not sufficiently soluble m nonpolar solvents to give a high enough concentration of the nucleophile to allow the reaction to occur at a rapid rate Other than the requirement that the solvent be polar enough to dis solve ionic compounds however the effect of solvent polarity on the rate of 8 2 reactions IS small What is most important is whether or not the polar solvent is protic or aprotic Water (HOH) alcohols (ROH) and carboxylic acids (RCO2H) are classified as polar protic solvents they all have OH groups that allow them to form hydrogen bonds... 

This difference in behavior for acetic acid in pure water versus water buffered at pH = 7 0 has some important practical consequences Biochemists usually do not talk about acetic acid (or lactic acid or salicylic acid etc) They talk about acetate (and lac tate and salicylate) Why Its because biochemists are concerned with carboxylic acids as they exist in di lute aqueous solution at what is called biological pH Biological fluids are naturally buffered The pH of blood for example is maintained at 7 2 and at this pH carboxylic acids are almost entirely converted to their carboxylate anions... 

What structural features are responsible for the reactivity order of carboxylic acid derivatives Like the other carbonyl containing compounds that we ve studied they all have a planar arrangement of bonds to the carbonyl group Thus all are about the same in offering relatively unhindered access to the approach of a nucleophile They differ m the degree to which the atom attached to the carbonyl group can stabilize the carbonyl group by electron donation... 

Hydrolysis of cinenn I gives an optically active carboxylic acid (+) chrysanthemic acid Ozonolysis of (+) chrysanthemic acid followed by oxidation gives acetone and an optically active dicarboxyhc acid (—) caronic acid (C7H10O4) What is the struc ture of (—) caronic acid" Are the two carboxyl groups cis or trans to each other What does this information tell you about the structure of (+) chrysanthemic acid" ... 

What is true for acetic acid is also true for other carboxylic acids at the ph ysiological pH that exists inside cells, carboxylic acids are almost entirely dissociated. To reflect this fact, we always refer to cellular carboxylic acids by the name of their anion—acetate, lactate, citrate, and so forth, rather than acetic acid, lactic acid, and citric acid. 

Photolysis of 8-1 gives an isomeric compound 8-2 in 83% yield. Alkaline hydrolysis of 8-2 affords a hydroxy carboxylic acid, 8-3, C25H3204. Treatment of 8-2 with silica gel in hexane yields 8-4, C24H2802. 8-4 is converted by NaI04-KMn04 to a mixture of 8-5 and 8-6. What are the structures of 8-2, 8-3, and 8-4 ... 

Though only an alkyl complex is possible in the ethylene insertion, there are several possible products of the C02 insertion, such as p -OCOH, p2-02CH, and p -COOH species, as shown in Figure 4. Thus, the following issues were investigated for the C02 insertion reactions (1) Which species is more easily formed, the metal-formate (M-OCOH) or the metal-carboxylic acid (M-COOH) (2) What are the most important interactions in the C02 insertion (3) How different is the C02 insertion from the C2H4 insertion ... 

Ions released into the matrix as the cement sets may interact with the organic part of the matrix. Metal ions, such as Ca + and AP+, may be chelated by car-boxylate groups, either on the polymer or on the tartaric acid additive. These have been considered in reasonable detail in the literature [230]. What has received far less attention is the possibility that fluoride ions might interact with carboxylic acid groups, either to modify the setting reaction or to become relatively securely anchored within the set cement. This possibility was raised in a review published in 1998 [230], but has not been followed up subsequently. It is based on the well-established observation that fluoride ion will form extremely strong hydrogen bonds with carboxylic acids in aqueous solution. They are of the type ... 

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