Concept explainers
Interpretation:
Given that to be
Concept introduction:
According to Huckel’s rule, a molecule orb an ion or bradical will be stable and aromatic if it is planar, cyclic and conjugated (4n+2) electrons. For a cyclic system to be aromatic both conditions are to be satisfied. If only one of the conditions is satisfied the specie will not be aromatic, becomes less stable and cannot be synthesized.
To explain:
The observation that cyclodecapentaene fulfills one of the criteria for aromaticity but not the other and has resisted all attempts at synthesis.
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Chapter 15 Solutions
Organic Chemistry
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- Describe briefly with either UV-Vis or IR spectroscopic method that could be employed to distinguish one compound from the other for the following pairs: (1) H,C=CHCH=CH, and HC=CCH,CH, (2) CH,CH,CH,CH, and CH,-CHCH,CH,Oнarrow_forwardGive reasons: (i) C—Cl bond length in chlorobenzene is shorter than C—Cl bond length in CH3—Cl.(ii) The dipole moment of chlorobenzene is lower than that of cyclohexyl chloride.(iii) SN1 reactions are accompanied by racemization in optically active alkyl halidesarrow_forward(a) Thiamin, or vitamin B, contains a positively charged five-membered nitrogen-sulfur heterocycle called a thiazolium ring. Determine if the pyrimidine ring and thiazolium ring are aromatic or not, and explain your answer. H₂C منایا؟ pyrimidine ring NH₂ thiazolium ring CH3 OHarrow_forward
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning