Which among the following pairs of structures will give different products on ozonolysis? (Consider the double bonds in the structures are rigid and not delocalized.)

During ozonolysis of a rigid Kekulé benzene structure, the $$\mathrm{C=C}$$ bonds are cleaved while the $$\mathrm{C-C}$$ single bonds remain intact.

The resulting two-carbon fragments depend on the substituents attached to the intact single bonds:

$$\mathrm{-CH-CH- \rightarrow Glyoxal\ (CHO-CHO)}$$

$$\mathrm{-C(CH_3)-CH- \rightarrow Methylglyoxal\ (CH_3-CO-CHO)}$$

$$\mathrm{-C(CH_3)-C(CH_3)- \rightarrow Dimethylglyoxal\ (CH_3-CO-CO-CH_3)}$$

For $$\mathrm{o\text{-}xylene}$$, the two Kekulé structures produce different fragment distributions.

In the first structure:

$$\mathrm{2\ Methylglyoxal + 1\ Glyoxal}$$

are formed.

In the second structure:

$$\mathrm{1\ Dimethylglyoxal + 2\ Glyoxal}$$

are formed.

Thus, shifting the localized double bonds changes the product distribution in $$\mathrm{o\text{-}xylene}$$.

For $$\mathrm{m\text{-}xylene}$$, $$\mathrm{p\text{-}xylene}$$, and toluene, both Kekulé structures give identical fragment distributions.

Correct Option: $$\mathrm{(C)}$$