Question

Question: Rank the following compounds in order of increasing stability.

a.

b.

c.

Short answer

Answer

Isolated dienes are higher in energy than conjugated dienes. Thus, the greater the conjugation, the greater its stability will be.The stability order is as shown below for the given compounds:

a > b > c

Step-by-step solution

Conjugated dienes

If the double bonds are separated by one single sigma bond, the diene is called conjugated diene.

The IUPAC system names dienes in the same way as alkenes, except that the suffix –diene is used.

Isolated dienes

The diene is called an isolated system if the double bonds are separated by more than one single sigma bond.

Alkenes containing two carbon-carbon double bonds are called dienes.

Determination of the type of stability

a.

Compound a.

Isolated double bonds

b.

Compound b.

Two conjugated double bonds intermediate stability

c.

Compound c.

Three conjugated double bonds most stable

The stability order is as shown below for the given compounds: .

a > b> c >