Introduction

Among the classes of organic compounds, we have now looked at hydrocarbons and those with single bonds joining carbon to oxygen, sulfur, or halogens. This chapter is devoted to amines, which have single bonds between carbon and nitrogen. The amines are present in so many kinds of essential biomolecules and important pharmaceutical agents that they are worthy of a chapter to themselves.

Consider that DNA, the blueprint for our heredity, relies on cyclic amines to carry the code that directs the synthesis of all of our proteins (Section 26.10), or that many of the biomolecules that carry chemical messages from place to place in our bodies are amines (the hormones and neurotransmitters, Chapter 20). Histamine, for example, the compound that initiates hay fever and other allergic reactions, is an amine. Therefore, many of the drugs that we use to mimic or to control the activity of histamine, the antihistamines present in cold and allergy medications, are amines. These are but a few examples of the biochemical roles played by amines.

In this chapter we'll consider the following questions:

1. What are the different types of amines?
The goal: Be able to recognize primary, secondary, tertiary, and heterocyclic amines, as well as quaternary ammonium ions.

2. How are amines named?
The goal: Be able to name simple amines and write their structures, given the names.

3. What are the general properties of amines?
The goal: Be able to describe amine properties such as hydrogen bonding, solubility, boiling point, and basicity.

4. How do amines react with water and acids?
The goal: Be able to predict the products of the acid-base reactions of amines and ammonium ions.

5. What are alkaloids?
The goal: Be able to describe the sources of alkaloids, name some examples, and tell how their properties are typical of amines.