Question

Draw the structures and provide systematic names for parts a, b, and c by substituting a chlorine for a hydrogen of methylcyclohexane:

a. A primary alkyl halide

b. A tertiary alkyl halide

c. Three secondary alkyl halides

Short answer

A halogen is connected to a primary carbon in a primary alkyl halide.

A halogen is bonded to a secondary carbon in a secondary alkyl halide.

A halogen is connected to a tertiary carbon in a tertiary alkyl halide.

Step-by-step solution

Establish the distinction between primary, secondary, and tertiary halides

A halogen is connected to a primary carbon in a primary alkyl halide.

A halogen is bonded to a secondary carbon in a secondary alkyl halide.

A halogen is connected to a tertiary carbon in a tertiary alkyl halide.

Step 2: Replace a chlorine for a hydrogen of methylcyclohexane to get a primary halide.

One hydrogen is replaced from the methyl group (-CH₃) attached to the cyclohexane ring to get a primary halide.

Replace a chlorine for a hydrogen of methylcyclohexane to get a tertiary alkyl halide.

One hydrogen is replaced from the methyl group (-CH₂) of the cyclohexane ring to get a tertiary halide.

 Step 4: Replace a chlorine for a hydrogen of methylcyclohexane to get three secondary alkyl halides.

One hydrogen is replaced from the methyl group (-CH₂) of the cyclohexane ring from the ortho, meta, and para positions to get three secondary alkyl halides.

Assigning IUPAC names

Alkyl halides are classified as substituted alkanes in the IUPAC system. The halogen prefixes all ends in "o." (i.e., fluoro, chloro, bromo, and iodo). As a result, alkyl halides are often referred to as haloalkanes.