Concept explainers
Which of the molecules and ions given in Problem 21.15 are aromatic according to the Hückel criteria? Which, if planar, would be antiaromatic?
21.15 State the number of 2p orbital electrons in each molecule or ion.
(a)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are five
Huckel’s rule of aromaticity
(b)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are six
Huckel’s rule of aromaticity
The given compound is planar. So, it is expected to possess aromaticity due to the expected effective delocalization of
(c)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are two
Huckel’s rule of aromaticity
The given compound is planar. So, it is expected to possess aromaticity due to the expected effective delocalization of
(d)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are two
Huckel’s rule of aromaticity
(e)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are two
Huckel’s rule of aromaticity
(f)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are two
Huckel’s rule of aromaticity
The given compound is planar. So, it is expected to possess aromaticity due to the expected effective delocalization of
(g)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are three
Huckel’s rule of aromaticity
(h)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are three
Huckel’s rule of aromaticity
(i)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are four
Huckel’s rule of aromaticity
(j)
Interpretation:
Which of the given molecules and ions are aromatic according to the
Concept Introduction:
The term aromaticity means “extreme stability”. So, aromatic compounds are highly stable compounds whereas anti-aromatic compounds are highly unstable compounds.
The aromatic compounds and anti-aromatic compounds can be distinguished based on Huckel’s rule of aromaticity.
Huckel’s rule of aromaticity is
If
If
If
Explanation of Solution
The given compound is shown here:
There are three
Huckel’s rule of aromaticity
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Chapter 21 Solutions
Organic Chemistry
- Of Hückel's original rules for aromaticity, one needed to be revised. Which one is it? The ring system must be planar. There must be (4n + 2) pi electrons. The molecule must be monocyclic. The pi electrons must be resonance delocalized over the entire ring. QUESTION 17arrow_forward3) In the mid-1930s, the German theoretical chemist Erich Hückel developed a rule that dealt with the aromaticity of various compounds, which became known as the Hückel Rule. Which (parts) of the compounds listed below are aromatic? Justify your answer based on Hückel's rule. You can treat the rings separately or together as you wish. IMAGE IV: colchicine: a highly poisonous alkaloid, obtained from autumn turmeric and used to treat gout.arrow_forward3) In the mid-1930s, the German theoretical chemist Erich Hückel developed a rule that dealt with the aromaticity of various compounds, which became known as the Hückel Rule. Which (parts) of the compounds listed below are aromatic? Justify your answer based on Hückel's rule. You can treat the rings separately or together as you wish.image iv: colchicine: a highly poisonous alkaloid,obtained from autumn turmeric and used to treat gout.arrow_forward
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- if boron replaces acarbon in a benzene ring, is the ring still aromatic? or is it antiaromaticarrow_forwardWhat is Resonance Theory? Sate five conclusions that can be drawn from the theory. State the two main experiments that were used to establish the extra stability of the benzene molecule. What are the factors that confer Aromaticity to an organic molecule? i. State the effects of substituents on a benzene derivative towards further aromatic substitution. Based on the above suggest the various types of substituents that can be attached to Benzene. What are the various ways by which alkenes may be synthesized? i. Give two examples each of Unsymmetrical alkenes and reagents. Give two examples of reactions of alkenes that result in Anti-Markonikov’s addition productsarrow_forwardIs the molecule aromatic, anti-aromatic, or non aromatic?arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningOrganic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning