Organic Chemistry
Organic Chemistry
8th Edition
ISBN: 9781305580350
Author: William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher: Cengage Learning
Question
Book Icon
Chapter 20, Problem 20.19P
Interpretation Introduction

Interpretation: Among the given two molecules, the major product that is formed by 1,2-addition of HCl to cyclopentadiene has to be found and explained.

Concept Introduction:

Addition reaction of dienes:

The diene with a four carbon system is 1,3-butadiene. When it is allowed to react with two moles of HBr, it undergoes two type of addition reactions such as 1,2-addition and 1,4-addition as shown here:

Organic Chemistry, Chapter 20, Problem 20.19P

1,3-butadiene reacts with H-Br and formed a resonance stabilized carbocation. The addition of a bromine atom to each of the two resonance forms has formed the corresponding product. So, two products are obtained. In one product the bromine atom has been attached to the 2nd carbon atom indicating that it has been formed from 1,2-addition whereas in the other product, the bromine atom has been attached to the 1st carbon atom indicating that it has been formed from 1,4-addition.

Blurred answer
Students have asked these similar questions
Elimination of HBr from 2-bromobutane affords a mixture of 1-butene and 2-butene. With sodium ethoxide as base, 2-butene constitutes 81% of the alkene products, but with potassium tert-butoxide, 2-butene constitutes only 67% of the alkene products. Offer an explanation for this difference.
Which reaction would you expect to be faster, addition of HCl to 2-methyl-1-butene or to 1-butene? Explain.
When carrying out this two step procedure (bromination and subsequent elimination) on cyclopentene, the lab students were surprised to find out that an alkyne was not the final product. What would the final product most likely be?

Chapter 20 Solutions

Organic Chemistry

Ch. 20.6 - Prob. 20.11PCh. 20.6 - Prob. 20.12PCh. 20 - If an electron is added to 1,3-butadiene, into...Ch. 20 - Prob. 20.15PCh. 20 - Predict the structure of the major product formed...Ch. 20 - Predict the major product formed by 1,4-addition...Ch. 20 - Predict the structure of the major 1,2-addition...Ch. 20 - Prob. 20.19PCh. 20 - Prob. 20.20PCh. 20 - Prob. 20.21PCh. 20 - Prob. 20.22PCh. 20 - Prob. 20.23PCh. 20 - Pyridine exhibits a UV transition of the type n at...Ch. 20 - Prob. 20.25PCh. 20 - Prob. 20.26PCh. 20 - Prob. 20.27PCh. 20 - Write the frontier molecular orbital analysis for...Ch. 20 - Prob. 20.29PCh. 20 - Draw structural formulas for the products of...Ch. 20 - Propose structural formulas for compounds A and B...Ch. 20 - Under certain conditions, 1,3-butadiene can...Ch. 20 - Prob. 20.33PCh. 20 - Prob. 20.34PCh. 20 - The following triene undergoes an intramolecular...Ch. 20 - Prob. 20.36PCh. 20 - Prob. 20.37PCh. 20 - Prob. 20.38PCh. 20 - Prob. 20.39PCh. 20 - The Diels-Alder reaction is not limited to making...Ch. 20 - The first step in a synthesis of dodecahedrane...Ch. 20 - Bicyclo-2,5-heptadiene can be prepared in two...Ch. 20 - Prob. 20.43PCh. 20 - Prob. 20.44PCh. 20 - Following is a retrosynthetic scheme for the...Ch. 20 - Prob. 20.46PCh. 20 - Prob. 20.47PCh. 20 - Prob. 20.48PCh. 20 - Prob. 20.49PCh. 20 - Prob. 20.50PCh. 20 - What reaction presented in this chapter is...Ch. 20 - Claisen rearrangement of an allyl phenyl ether...Ch. 20 - Prob. 20.53PCh. 20 - Prob. 20.54PCh. 20 - We now continue the use of organic chemistry...Ch. 20 - Write the products of the following sequences of...
Knowledge Booster
Background pattern image
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
  • Text book image
    Organic Chemistry
    Chemistry
    ISBN:9781305580350
    Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
    Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning