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
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