Organic Chemistry-Package(Custom)
Organic Chemistry-Package(Custom)
4th Edition
ISBN: 9781259141089
Author: SMITH
Publisher: MCG
Question
Book Icon
Chapter 27, Problem 27.25P
Interpretation Introduction

(a)

Interpretation: The stereochemistry of given reaction is to be predicted.

Concept introduction: Cycloaddition reactions are pericyclic reactions that take place in two compounds containing pi bonds to form a cyclic compound. These reactions are concerted and stereospecific in nature. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in thermal conditions undergoes reaction in antrafacial fashion and polyene containing odd number of bonds undergo reaction in suprafacial fashion. The total number of bonds present in the alkenes is considered.

Interpretation Introduction

(b)

Interpretation: The stereochemistry of given reaction is to be predicted.

Concept introduction: Electrocyclic reactions involve ring opening or ring closure in a conjugated polyene. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in photochemical conditions undergoes reaction in disrotatory fashion and polyene containing odd number of bonds undergo reaction in conrotatory fashion.

Interpretation Introduction

(c)

Interpretation: The stereochemistry of given reaction is to be predicted.

Concept introduction: Cycloaddition reactions are pericyclic reactions that take place in two compounds containing pi bonds to form a cyclic compound. These reactions are concerted and stereospecific in nature. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in photochemical conditions undergoes reaction in suprafacial fashion and polyene containing odd number of bonds undergo reaction in antrafacial fashion. The total number of bonds present in the alkenes is considered.

Interpretation Introduction

(d)

Interpretation: The stereochemistry of given reaction is to be predicted.

Concept introduction: Sigmatropic rearrangements are pericyclic reactions which takes place by concerted mechanism. In these rearrangements migration of sigma bond takes place. According to Woodward-Hoffmann rules, the total number of electron pairs in sigma bond that is broken and the pi bonds that rearrange. The polyene containing even number of electron pairs and bonds in thermal conditions undergoes reaction in antrafacial fashion and polyene containing odd number of electron pairs and bonds undergo reaction in suprafacial fashion.

Blurred answer
Students have asked these similar questions
5) Construct the orbital correlation diagram for hexatriene-cyclohexadiene interconversion, to what extend this obeys the Woodward-Hoffmann rules? 6) Using the Woodward-Hoffmann rules, predict the stereochemistry of each reaction a. a [6 + 4] thearmal cycloaddition b. photochemical electrocyclic ring closure of 1,3,5,7,9-decapentaene c. a [1 + 3] photochemical sigmatropic rearrangement d. photochemical ring opening of 1,3,5-cyclooctatriene
What stereoisomers are obtained from the following reactions? a. 1-butene + H2O + H2SO4 b. cyclohexene + HBr c. cis-3-heptene + Br2 d. trans-3-hexene + Br2
8

Chapter 27 Solutions

Organic Chemistry-Package(Custom)

Knowledge Booster
Background pattern image
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
  • Text book image
    Organic Chemistry
    Chemistry
    ISBN:9781305080485
    Author:John E. McMurry
    Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9781305080485
Author:John E. McMurry
Publisher:Cengage Learning