bynzyne having one triple bond what about hybradation of all carbons ?

Answer 1

Benzyne is an example of an aryne (-yne = triple bond)
This is no ordinary triple bond as the second p 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 The ielectrostatic potential for benzyne.reveals that 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 reaBenzyne is stabilized by resonance between structures 1 and 2—a better representation of the electronic structure is 3. The "extra" pi bond (4b) is localised and orthogonal to the other pi bonds making up the atomatic ring (4a). Benzyne can also be drawn as a diradical: the pi bond 4b splits homolytically, leaving one electron on each of the two atoms that are formally part of that bond.

Benzyne is an extremely reactive species due to the nature of its triple bond. In normal acetylenic species (such as the simplest, ethyne) the unhybridized p orbitals are parallel to one another above and below the molecular axis. This facilitates maximum orbital overlap. In benzyne, however, the p orbtials are distorted to accommodate the triple bond within the ring system, reducing their effective overlap. A suitable chemical trap for benzyne is a cyclopentadiene.

Benzyne can be a ortho-, meta- and para-benzyne where the biradical can be a 1,2-, 1,3- and 1,4-biradical species respectively. Their energies in silico are respectively 106, 122, and 138 kcal/mole. The 1,4-biradical species has been identified in the Bergman cyclization. Professor Maitland Jones of Princeton University has studied the interconversion of the ortho-, meta - and para-benzynes.

Aryne reactivity can also be extended to carbon to carbon insertion reactions into substrates that can react both as a nucleophile and as an electrophile with for instance a malonic acid ester [6]. The precursor to benzyne in this reaction is 2-(Trimethylsilyl)phenyl triflate.

Answer 2

Four of the carbons outside the triple bond are sp2 hybridized. The triply bonded carbons are sp hybridized. People who don't believe in "benzyne" say that sixth bond is (+)C=C(-).