Concept explainers
Interpretation:
The structures of all possible adducts obtainable when the diene given reacts with one equivalent of HCl are to be given.
Concept introduction:
Conjugated dienes undergo electrophilic addition reactions through the formation of an allyl carbocation. The allyl cation is resonance stabilized and the attack of chloride ion on each of these forms leads to the formation of a mixture of 1, 2- and 1, 4-addition products.
To give:
The structures of all possible adducts obtainable when the diene given reacts with one equivalent of HCl.
Answer to Problem 16VC
The compound given is 1-vinylcyclopentene.The structures of all the possible adducts obtained when it reacts with one equivalent of HCl are given below.
Explanation of Solution
1-Vinylcyclopentene is an unsymmetrical conjugated diene. Protonation of the CH2 in double bond and that in the ring lead to the formation of two different allyl carbocations, each of which is in resonance with another form. Hence four carbocations as shown are possible. Attack of the chloride ion on each of these carbocation leads to the formation of four different products.
The compound given is 1-vinylcyclopentene.The structures of all the possible adducts obtained, when it reacts with one equivalent of HCl, are given below.
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning