Question

What is the meaning of the term tertiary \(\left(3^{\circ}\right)\) when it is used to classify amines? Draw a structural formula for the one tertiary \(\left(3^{\circ}\right)\) amine with the molecular formula \(\mathrm{C}_{4} \mathrm{H}_{11} \mathrm{~N}\).

Short answer

Answer: A tertiary amine, also known as a 3° amine, is an amine in which the nitrogen atom is bonded to three carbon atoms and no hydrogen atoms. An example of a tertiary amine with the molecular formula C4H11N is trimethylamine, with the structural formula: ``` H H H | | | H - C - N - C - C - H | | | H H H ```

Step-by-step solution

Understand primary, secondary, and tertiary amines

Amines are organic compounds that contain nitrogen (N) atoms bonded with carbon (C) and/or hydrogen (H) atoms. Amines can be classified as primary (1°), secondary (2°), or tertiary (3°) based on the number of carbon atoms directly bonded to the nitrogen atom: 1. Primary amines (1°): The nitrogen atom is bonded to one carbon atom and two hydrogen atoms. 2. Secondary amines (2°): The nitrogen atom is bonded to two carbon atoms and one hydrogen atom. 3. Tertiary amines (3°): The nitrogen atom is bonded to three carbon atoms and no hydrogen atoms.

Determine the structure of the tertiary amine with the molecular formula C4H11N

Based on the molecular formula C4H11N, we need to draw a tertiary amine (3°) with four carbon atoms, eleven hydrogen atoms, and one nitrogen atom. Recall that in a tertiary amine, the nitrogen atom is bonded to three carbon atoms and no hydrogen atoms. 1. First, put the nitrogen atom (N) in the center as it forms three bonds with carbon atoms. 2. Then, connect the nitrogen atom to three carbon atoms (C), as it is a tertiary amine. 3. Distribute the remaining carbon atoms (one in this case) between the bonded carbon atoms. 4. Finally, add hydrogen atoms (H) to the carbon atoms so that each carbon forms four bonds. Here's the structural formula for the tertiary amine with the molecular formula C4H11N: ``` H H H | | | H - C - N - C - C - H | | | H H H ``` This is a tertiary amine with the correct molecular formula, and it is called N,N,N-trimethylmethanamine or more commonly, trimethylamine.

Key concepts

Amine Classification

When we talk about amine classification, we are referring to the way we categorize amines based on the number of carbon-containing groups, or alkyl groups, that are directly attached to the nitrogen atom (N). Amines are vital organic compounds and they come in three main types - primary (1°), secondary (2°), and tertiary (3°).

A primary amine has one alkyl group linked to the nitrogen, while secondary amines have two, and tertiary amines have three. It's easy to remember if you associate the 'degree' notation with the number of carbon atoms attached:

• Primary (1°) amines: One carbon atom bonded to the nitrogen atom.
• Secondary (2°) amines: Two carbon atoms bonded to the nitrogen atom.
• Tertiary (3°) amines: Three carbon atoms bonded to the nitrogen atom, with no hydrogens attached directly to the nitrogen.

Tertiary amines are interesting because they have three carbon groups attached, which can result in various structures, depending on how the carbon atoms are connected. Each type of amine has its unique properties and applications, making the classification a useful tool for chemists to determine their behavior in chemical reactions.

Structural Formula

The structural formula is a graphical representation of the molecular structure of a compound, showing how atoms are connected. It is incredibly useful because it provides a visual aid to understand the compound's molecular geometry, the types of bonds between atoms, and the overall arrangement of the molecule.

In the case of tertiary amines, drawing the structural formula starts with positioning the nitrogen atom in the center because it is the common connection point for the three carbon atoms that must be attached to it. You can think of it as a hub in a wheel with spokes leading out to carbon atoms.Here are the steps simplified:

• Place the nitrogen atom (N) centrally.
• Attach three carbon atoms (C) to it, representing the 'tertiary' nature.
• Add the remaining carbon to form a chain or branch off from one of the bonded carbon atoms.
• Ensure every carbon atom satisfies the four-bond rule, adding hydrogen atoms (H) accordingly.

The importance of the structural formula cannot be overstated – it not only helps in understanding the molecular shape and predicting reactivity but is also vital in naming the compound as per IUPAC nomenclature, referring to specific atoms by their positions.

Organic Compounds

Diving into organic compounds, these are essentially the compounds mainly composed of carbon atoms, bonded with other elements like hydrogen, nitrogen, oxygen, and more. They are the foundation of all living organisms and are studied extensively in organic chemistry. The carbon atom's ability to form four covalent bonds and create long chains and complex structures is the core reason for the rich diversity of organic compounds.

Organic compounds are categorized into families based on their functional groups, which determine their chemical reactivity. Amines, for instance, are a family of organic compounds which contain the functional group -NH2, -NHR, or -NR2, where 'R' represents an alkyl or aryl group. Tertiary amines, as explored in both previous sections, fall into this category and exemplify how a single functional group's classification can lead to variation in compounds' properties.By studying organic compounds systematically, chemists can predict physical properties, reactivity, and even create new substances, which can have implications in fields ranging from pharmaceuticals to materials science.