Draw the structures of the following compounds:
(a) tert-butylamine
(b) α-aminopropionaldehyde
(c) 4-(dimethylamino)pyridine

Verified step by step guidance

1. Step 1: Understand the structure of tert-butylamine. The 'tert-butyl' group is a branched alkyl group with the formula (CH₃)₃C-. Attach an amine group (-NH₂) to the central carbon of the tert-butyl group. The resulting structure is (CH₃)₃C-NH₂.
2. Step 2: Analyze the structure of α-aminopropionaldehyde. The term 'α-amino' indicates that an amine group (-NH₂) is attached to the carbon adjacent to the aldehyde group (-CHO). Start with propionaldehyde (CH₃-CH₂-CHO), and add an amine group to the α-carbon (the carbon next to the aldehyde group).
3. Step 3: Break down the name 4-(dimethylamino)pyridine. Pyridine is a six-membered aromatic ring containing one nitrogen atom. The '4-' indicates that the substituent is attached to the fourth carbon relative to the nitrogen. The 'dimethylamino' group is -N(CH₃)₂, which is a nitrogen atom bonded to two methyl groups. Attach this group to the fourth carbon of the pyridine ring.
4. Step 4: Draw the structures for each compound based on the descriptions above. For tert-butylamine, draw a central carbon atom bonded to three methyl groups and one amine group. For α-aminopropionaldehyde, draw a three-carbon chain with an aldehyde group at one end and an amine group on the α-carbon. For 4-(dimethylamino)pyridine, draw a pyridine ring with a dimethylamino group attached to the fourth carbon.
5. Step 5: Verify the structures by checking that all valencies are satisfied and that the functional groups are correctly placed as per the IUPAC names provided in the problem.

Key Concepts

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. In organic chemistry, recognizing functional groups such as amines, aldehydes, and others is crucial for understanding the properties and reactivity of compounds. For example, tert-butylamine contains an amine group, which influences its basicity and solubility.

Structural Representation

Structural representation refers to the way in which the arrangement of atoms in a molecule is depicted. This can include Lewis structures, condensed formulas, or skeletal structures. Accurately drawing these structures is essential for visualizing molecular geometry and understanding how different atoms are connected, which is vital for compounds like a-aminopropionaldehyde and 4-(dimethylamino)pyridine.

Isomerism

Isomerism is the phenomenon where compounds with the same molecular formula can have different structures or arrangements of atoms. This concept is important when drawing organic compounds, as different isomers can exhibit distinct physical and chemical properties. For instance, the presence of different substituents in 4-(dimethylamino)pyridine can lead to various isomeric forms, affecting their reactivity and interactions.