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Benzyne

Structure
 

Benzyne
 Benzyne is an example of an aryne (-yne = triple bond) 
This is no ordinary triple bond as the second π interaction results from a weak interaction of sp2 hybrid orbitals lying in the plane of the ring. 
The triple bond is non-linear due to the constraints of the 6-membered ring. 
Benzyne is strained and highly reactive.		 orbitals involved in the triple bond in benzyne

Reactivity

electrostatic potential of benzyne The image shows the electrostatic potential for benzyne. 
The more red an area is, the higher the electron density and the more blue an area 
is, the lower the electron density. 

Here we see the triple bond as a region of high electron density (red). 
As a result of the non-linear triple bond, benzyne is highly reactive. 
Benzyne is a reactive intermediate, an tends to undergo addition reactions.
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organic chemistry © Dr. Ian Hunt, Department of Chemistry University of Calgary