Organic Chemistry: Concepts and Applications - Headley Allan D. 2020

Carbon Functional Groups and Organic Nomenclature
2.1 Introduction

There are practically millions of different organic compounds that exist today and research labs and various industries, especially the pharmaceutical industry, are constantly synthesizing new ones. As scientists, it is very difficult, if not impossible to study all these compounds individually. One approach to better understand the chemistry of the numerous compounds is to classify them into different groups and then study the properties and reactions of the various groups. Organic compounds can be classified into various groups based on specific atomic arrangements that are common within molecules. The groups that are used to classify organic molecules are known as functional groups. The physical and chemical properties of compounds that contain a particular functional group tend to be similar. For example, molecules that contain the ─OH group are known as alcohols. Rubbing alcohol (isopropanol) is one example of an alcohol and another is ethyl alcohol, which is used as an organic solvent; methanol is another example of an alcohol, which is used as a fuel. Molecules that contain the ─NH₂ group are classified as amines. Amino acids are a well-known group of molecules that contain the amine and carboxylic acid functionalities; amino acids are the essential building blocks of protein and life. A wide variety of medicines contain the amine functionality. Morphine and demerol that are commonly used as analgesics are amines, and novocain is an amine that is commonly used as an anesthetic. Many insecticides are amines, and amines are also widely used in the tanning industry and the manufacture of dyes. Ketones and aldehydes are two other functional groups that are found in many compounds that are commonly used; ketones and aldehydes are some of the key components of perfumes and they are commonly used solvents. For example, acetone is the key component in nail polish remover. Shown in Figure 2.1 are well-known molecules in which functional groups have been highlighted.