(a)
Interpretation: The triene that has largest heat of hydrogenation is to be predicted.
Concept introduction: Conjugated diene consists of two double bonds that are separated by a single bond, whereas isolated diene also consists of two double bond but they are separated by two or more carbon atoms.
The stability of conjugated diene is more than isolated diene. Due to which the heat of hydrogenation is smaller for conjugated diene, whereas heat of hydrogenation for isolated diene is larger.
(b)
Interpretation: The triene that has smallest heat of hydrogenation is to be predicted.
Concept introduction: Conjugated diene consists of two double bonds that are separated by a single bond, whereas isolated diene also consists of two double bond but they are separated by two or more carbon atoms.
The stability of conjugated diene is more than isolated diene. Due to which the heat of hydrogenation is smaller for conjugated diene, whereas heat of hydrogenation for isolated diene is larger.
(c)
Interpretation: The triene that absorbs the longest
Concept introduction: Conjugated diene consists of two double bonds that are separated by a single bond, whereas isolated diene also consists of two double bond but they are separated by two or more carbon atoms.
The energy difference between the ground and excited state decreases when number of conjugated bonds increases. Due to this absorption shifts to the longer wavelengths.
(d)
Interpretation: The triene that is most reactive in the Diels-Alder reaction is to be predicted.
Concept introduction: Conjugated diene consists of two double bonds that are separated by a single bond, whereas isolated diene also consists of two double bond but they are separated by two or more carbon atoms.
The stability of conjugated diene is more than isolated diene.
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Chapter 16 Solutions
Organic Chemistry
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Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning