Functional groups, organic amide

Amides are compounds with the C -N functional group. Without amides, there would be no life. As we ll see in the next chapter, the amide bond between nitrogen and a carbonyl-group carbon is the fundamental link used by organisms for forming proteins. In addition, some synthetic polymers such as nylon contain amide groups, and important pharmaceutical agents such as acetaminophen, the aspirin substitute found in Tylenol and Excedrin, are amides. 

The chemistry of carboxylic acids is the central theme of this chapter The impor tance of carboxylic acids is magnified when we realize that they are the parent com pounds of a large group of derivatives that includes acyl chlorides acid anhydrides esters and amides Those classes of compounds will be discussed m Chapter 20 Together this chapter and the next tell the story of some of the most fundamental struc tural types and functional group transformations m organic and biological chemistry... 

Amides, like esters, are abundant in all living organisms—proteins, nucleic acids, and many pharmaceuticals have amide functional groups. The reason for this abundance of amides, of course, is that they are stable to the conditions found in living organisms. Amides are the least reactive of the common acid derivatives and undergo relatively few nucleophilic acyl substitution reactions. 

Rhodium precipitation in solubilized rhodium-phosphite complex catalyzed liquid recycle hydroformylation may be minimized or prevented by carrying out product recovery in the presence of an organic polymer containing polar functional groups such as amides, ketones, carbamates, ureas and carbonates.[20] Patent examples include the use of polyvinylpyrrolidone and vinylpyrrolidone-vinyl acetate copolymer with diorganophosphite-modified rhodium catalysts. 

The amino acids link together by the reaction of an amino group of one amino acid with the carboxylic acid group of another amino acid. This forms a peptide bond. (For the sake of clarity the + signs in the reaction have been omitted.) A peptide bond is an amide group in molecules that are not biochemical. Many functional groups have different names in organic chemistry and in biochemistry. 

IR spectroscopy is useful for the identification of some of the functional groups in an organic molecule. The technique also provides a fingerprint of the molecule and its comparison with authentic specimen often confirms the structure of that molecule. The IR spectra of AHLs show characteristic absorption peaks at 1780,1710,1650 cm-1 arising from the lactone ring, 3-oxo (when present), and amide carbonyl, respectively [15,16]. 

Almost all organic functional groups except for olefinic double bonds are reduced by hthium aluminum hydride. It reduces acids, esters, acid chlorides, amides, imides, imines, nitriles, nitroorganics, epoxides, and lactones. 

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