Benzene | Benzyne | |
|---|---|---|
Identification | Alternating single and double bonds. | Alternating single and double bonds plus an extra pie bond (triple bond) between two adjacent carbons. |
Structure |  |  |
Nature | Benzene is not a reactive intermediate but a starting material for many aromatic reactions. | It is a reactive intermediate formed from an elimination reaction and later undergoes an addition reaction. |
Stability | Highly stable and can be isolated. | Highly unstable and cannot be isolated. It is generated in situ (during the reaction). |
Bond Type |
All three pie bonds are formed by the lateral overlap of the p -orbitals (p-p overlap).
 | The pie bonds are of two types- p-p and sp2-sp2. The p-p orbital overlap forms the three conjugated pie bonds. These pie bonds are all in one plane. The additional pie bond of the triple bond is due to the lateral overlap of the sp2 orbitals of two carbon atoms (sp2-sp2), which is perpendicular to the p-orbitals, therefore, not conjugated.
 |
Aromatic Nature | Benzene is aromatic due to pie electron delocalization. | Benzyne is also aromatic due to p-orbital electron delocalization. The electrons associated with the triple bond are not part of the electron delocalization since it is part of another perpendicular plane. |
Bond strength and strain | Benzene has high bond strength and no angle strain. | The triple bond of benzyne has low bond strength and high angle strain, so it rapidly reacts further. |
Type of reaction | Benzenes easily undergo aromatic electrophilic addition reactions. | Benzynes easily undergo nucleophilic addition and cycloaddition reactions. |
Organic_Chemistry_Basics_Free
