Names of Some Carboxylic Acids

Systematic name Trivial name Systematic name Trivial name 

The names in parentheses are abandoned but are listed for reference to older literature. 

Examples of various crown ethers and cryptands are shown here. The top line of compounds may be named readily enough although the problem with this semi-systematic approach is obvious. If two methylenes were added to 18-crown-6, the compound could correctly be called 20-crown-6 but in the absence of unequivocal descriptors, the positions of the 3-carbon bridges would be unclear. The more cumbersome name 1,4,7,11,13,17-hexaoxacy-cloicosane tells clearly that the longer bridges are adjacent to each other. A similar problem is apparent in the last two entries of the second line. The designations dicyclohexano and dibenzo are clear as to the substituents but not their positions. The semi-systematic nomenclature is widely used, however, because it is so much less cumbersome for most purposes. 

13-diaza-18-crown-6 N,N -dibenzyl-4.13- dicyclohexano-18-crown-6 dibenzo-18-crown-6 diaza-18-crown-6 

An additional nuance in the nomenclature of these compounds concerns their complexes. The open-chained compounds are often referred to as podands and their complexes as podates. The cyclic ethers may also be called coronands and their complexes are therefore coronates. Complexed cryptands are cryptates. The even more complicated structures known as spherands, cavitands, or carcerands are called spherates, cavitates, or carcerates, respectively, when complexed. The combination of a macrocycle (crown ether or coro-nand) and a sidechain (podand) is typically called a lariat ether. 

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Table 20.1 Common Names of Some Carboxylic Acids and Acyl Groups...

Table 12.3 Names and Structures of Some Carboxylic Acids...

Figure 12-1 shows the structures of some carboxylic acids, and their common names and lUPAC names are given in the following list. Figure 12-2 shows the structures and names of some of carboxylic acid salts. 

Several aliphatic carboxylic acids have been known for centuries, and their common names reflect their historical sources. Formic acid was extracted from ants formica in Latin. Acetic acid was isolated from vinegar, called acetum ( sour ) in Latin. Propionic acid was considered to be the first fatty acid, and the name is derived from the Greek protos pion ( first fat ). Butyric acid results from the oxidation of butyraldehyde, the principal flavor of butter butyrum in Latin. Caproic, caprylic, and capric acids are found in the skin secrehons of goats caper in Lahn. The names and physical properties of some carboxylic acids are listed in Table 20-1. 

TABLE 20-1 Names and Physical Properties of Some Carboxylic Acids I ... 

Common names for some aldehydes are widely used. The common names for the aldehydes are derived from the common names of the carboxylic acids (see Table 19.7). The -ic acid or -oic acid ending of the acid name is dropped and is replaced with the suffix -aldehyde. Thus the name of the one-carbon acid, formic acid, becomes formaldehyde for the one-carbon aldehyde ... 

TABLE 14.1 Names and Condensed Structural Formulas of Some Carboxylic Acids Condensed Structural Formula lUPAC Name Common Name Ball-and-Stick Model... 

To name a simple carboxylic acid, follow the steps below. Figure 1.24 gives some examples of carboxylic acid names. 

The nomenclature for this homologous series is somewhat confused. The term PANs has been used historically to denote peroxyacyl nitrates, and this terminology continues to be used extensively in the literature, despite the lack of adherence to traditional IUPAC rules of nomenclature. Because the PANs can be considered to be mixed anhydrides of carboxylic acids and nitric acid, another suggestion (Roberts, 1990) has been peroxyacetic nitric anhydride for CH,C(0)00NO2 and peroxy carboxylic nitric anhydrides for the whole class of compounds. Although it does not follow the IUPAC rules, it would be consistent with the widespread use of the name PAN but also reflect the structure more accurately. Table 6.20 shows the structures and commonly used names of some PANs that have been observed in the atmosphere and/or in laboratory studies. 

The names and structures of some fatty acids are summarized in Table 8-1. Notice that these acids have straight carbon chains and may contain one or more double bonds. Except for the smallest members of the series, which are soluble in water, fatty acids are strongly hydrophobic. However, they are all acids with pKa values in water of 4.8. To the extent that free fatty acids occur in nature, they are likely to be found in interfaces between lipid and water with the carboxyl groups dissociated and protruding into the water. However, most naturally occurring fatty acids... 

The first authentic synthesis of a bisphosphonic acid, l-hydroxyethane-l,l-bisphos-phonic acid (etidronic acid), was published by von Baeyer and Hofmann in 1897 [1], although it is possible that the same compound had already been obtained in 1865 by Menschutkin [2], The synthetic approach to BPs employed today differs only little from that used over a hundred years ago, and it is still based on the reaction of a carboxylic acid with phosphorus trichloride with the addition of some water [3], (Note BPs are usually represented as the free bisphosphonic acids the generic names given refer, however, to their salt forms.)... 

Common Names of Dicarboxylic Acids A dicarboxylic acid (also called a diacid) is a compound with two carboxyl groups. The common names of simple dicarboxylic acids are used more frequently than their systematic names. A common mnemonic for these names is Oh my, such good apple pie, standing for oxalic, malonic, succinic, glutaric, adipic, and pimelic acids. The names and physical properties of some dicarboxylic acids are given in Table 20-2. 

The names of esters consist of two words that reflect their composite structure. The first word is derived from the alkyl group of the alcohol, and the second word from the carboxylate group of the carboxylic acid. The IUPAC name is derived from the IUPAC names of the alkyl group and the carboxylate, and the common name is derived from the common names of each. The following examples show both the IUPAC names and the common names of some esters ... 

Some carboxylic acids are called fatty acids because they come from fats or lipids. The interesting thing is that if the fat is boiled with sodium hydroxide solution it breaks up. The sodium salts of the acids are soft to the skin, lather in water and are called soaps . This breaking up of the fat ester into the soap is called saponification . Soaps contain groups like RCOONa, where R is CH3(CH2)i6COO-or sodium stearate. Other long-chain acids in soaps are mixtures of palmitic acid, oleic acid, hence the name Palmolive ... 

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