Order of bond energy in furan, pyrolle and thiophene

In summary, the question is asking for the correct order of bond energy required for heterolytic cleavage of the C-Br bond in furan, pyrrole, and thiophene, which have a bromo-methyl group attached adjacent to the N, O, and S atoms respectively. The attempt at a solution suggests that the lone pairs participating in resonance in all three molecules would make the only difference in their electronegativity. However, the correct order of bond energy required is not as expected.
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Krushnaraj Pandya
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Homework Statement


A bromo-methyl group is attached adjacent to the N,O and S atoms respectively in furan, pyrolle and thiophene, find correct order of bond energy required for heterolytic cleavage of CBr bond forming carbocation

2. The attempt at a solution

Lone pairs participate in resonance in all three, so I thought the only different thing is the elctronegativity of the atoms. Since Oxygen>Nitrogen>Sulphur in EN furan would be most unstable since it'd try to pull electrons from the already positive carbon so its bond energy should be highest, then pyrolle's then thiophene but this is incorrect. I'd appreciate some help, thank you
 
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Related to Order of bond energy in furan, pyrolle and thiophene

1. What is bond energy?

Bond energy is the amount of energy required to break a chemical bond between two atoms. It is typically measured in kilojoules per mole (kJ/mol).

2. How does bond energy affect the stability of a molecule?

The higher the bond energy, the more stable a molecule is. This is because stronger bonds are more difficult to break, making the molecule less likely to undergo chemical reactions or decompose.

3. What is the general order of bond energy in furan, pyrrole, and thiophene?

The general order of bond energy in these molecules is thiophene > pyrrole > furan. This means that thiophene has the strongest bonds, followed by pyrrole, and then furan.

4. Why does thiophene have the highest bond energy?

Thiophene has the highest bond energy because it contains sulfur, which forms stronger bonds than oxygen (found in furan) and nitrogen (found in pyrrole). The larger atomic radius of sulfur also contributes to the stronger bonds in thiophene.

5. How does the order of bond energy affect the properties of furan, pyrrole, and thiophene?

The higher bond energy in thiophene makes it a more stable molecule, which can affect its reactivity, boiling point, and other physical and chemical properties. Pyrrole and furan, with weaker bonds, may be more reactive and have lower boiling points.

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