9. Alkenes and Alkynes
Alkene Stability
10PRACTICE PROBLEM
A double bond is usually more stable in an endocyclic position of a five-membered ring than in the exocyclic position. Comparing the estimated hydrogenation energies of the two pairs given below.
The first pair shows an energy difference of about 5 KJ/mol while the second pair shows an energy difference of about 9 KJ/mol.
Explain this discrepancy and suggest which number should be trusted under this effect.
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A double bond is usually more stable in an endocyclic position of a five-membered ring than in the exocyclic position. Comparing the estimated hydrogenation energies of the two pairs given below.
The first pair shows an energy difference of about 5 KJ/mol while the second pair shows an energy difference of about 9 KJ/mol.
Explain this discrepancy and suggest which number should be trusted under this effect.