Question

Name each of the following:

Short answer

The names of the given skeletal structures are:

a) (E)-2-heptene

b) (Z)-3,4-dimethyl-2-pentene

c) (Z)-1-chloro-3-ethyl-4-methyl-3-hexene

Step-by-step solution

Step 1: The skeletal structure

In this series of atoms bonded together, it is a form of the essential structure of the compound. This skeleton can consist of chairs, branches, and rings of bonded atoms. Example: The skeletal structure of a sec-butyl tert-butyl ether is shown below.

Here, the carbon atom is shown as corners. Bonding is shown by a line. Single bond single line, double bond double line, triple bond triple line.

Definition of the cis and trans isomer

Isomers are compounds with the same molecular formula but with a different arrangement of atoms.

Cis-isomer is represented with both the substituents pointing in one direction.

Trans-isomer is represented with both the substituents pointing in opposite directions.

Steps to follow while drawing E and Z isomers.

1. Assign the priority order to the groups on the basis of atomic number. The higher atomic number gets the highest priority.

2. If higher priority groups are on the same side, then it will be a Z isomer as shown below.

3. If higher priority groups are on the different side, then it will be an E isomer as shown below.

Subpart (a)

The naming rule as per IUPAC is performed by first selecting the largest parent chain. Then start the numbering of carbon from wherethe functional group or some double or triple bond is closest.

Therefore, the name of the given compound is (E)-2-heptene

Subpart (b)

The naming rule as per IUPAC is performed by first selecting the largest parent chain. Then start the numbering of carbon from where the functional group or some double or triple bond is closest.

Therefore, the name of the given compound is (Z)-3,4-dimethyl-2-pentene.

Subpart (c)

The naming rule as per IUPAC is performed by first selecting the largest parent chain. Then start the numbering of carbon from where the functional group or some double or triple bond is closest.

Therefore, the name of the given compound is(Z)-1-chloro-3-ethyl-4-methyl-3-hexene.