MASTERINGCHEM FOR ORGANIC CHEM STANDAL
MASTERINGCHEM FOR ORGANIC CHEM STANDAL
13th Edition
ISBN: 9781269517553
Author: Bruice
Publisher: PEARSON
Question
Book Icon
Chapter 28.5, Problem 18P

(a)

Interpretation Introduction

Interpretation:

It should be identified that will a thermal 1, 3-migrations of carbon occur with whether retention or inversion of configuration.

Concept introduction:

Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”.  There is a single transition state from start to finish, in contrast to a stepwise reaction.

There are mainly three types of pericyclic reactions,

  1. 1) Electrocyclic reactions
  2. 2) Cycloaddition reactions
  3. 3) Sigmatropic reactions

In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  1

Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.

Migration of carbon and hydrogen will occur in a sigmatropic rearrangement reaction.

When hydrogen migrates in a sigmatropic rearrangement, the s orbital of the hydrogen is partially bonded to both the migration origin and the migration terminus in the transition state.

Migration of hydrogen in suprafacial and antarafacial rearrangement can be represented as follows,

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  2MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  3

Migration of carbon occurs through two ways because it has a two lobed p orbital. Carbon can simultaneously interact with the migration origin and the migration terminus using one lobe of its p orbital.

Migration of carbon in suprafacial and antarafacial rearrangement can be represented as follows,

Carbon migrating with one lobe of its p orbital interacting

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  4 MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  5

Carbon migrating with both lobe of its p orbital interacting

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  6MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  7

Inversion of configuration is the inversion of a chiral center in a molecule in a chemical reaction.

Retention of configuration is the preservation of integrity of the spatial arrangement of bonds to a chiral center during a chemical reaction.

(b)

Interpretation Introduction

Interpretation:

It should be identified that will a thermal 1, 5-migrations of carbon occur with whether retention or inversion of configuration.

Concept introduction:

Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”.  There is a single transition state from start to finish, in contrast to a stepwise reaction.

There are mainly three types of pericyclic reactions,

  1. 1) Electrocyclic reactions
  2. 2) Cycloaddition reactions
  3. 3) Sigmatropic reactions

In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  8

Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.

Migration of carbon and hydrogen will occur in a sigmatropic rearrangement reaction.

When hydrogen migrates in a sigmatropic rearrangement, the s orbital of the hydrogen is partially bonded to both the migration origin and the migration terminus in the transition state.

Migration of hydrogen in suprafacial and antarafacial rearrangement can be represented as follows,

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  9MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  10

Migration of carbon occurs through two ways because it has a two lobed p orbital.  Carbon can simultaneously interact with the migration origin and the migration terminus using one lobe of its p orbital.

Migration of carbon in suprafacial and antarafacial rearrangement can be represented as follows,

Carbon migrating with one lobe of its p orbital interacting

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  11 MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  12

Carbon migrating with both lobe of its p orbital interacting

MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  13MASTERINGCHEM FOR ORGANIC CHEM STANDAL, Chapter 28.5, Problem 18P , additional homework tip  14

Inversion of configuration is the inversion of a chiral center in a molecule in a chemical reaction.

Retention of configuration is the preservation of integrity of the spatial arrangement of bonds to a chiral center during a chemical reaction.

Blurred answer
Students have asked these similar questions
Why C=O in concentrated/pure aliphatic carboxylic acid appear at lower stretching frequency (1710 cm-1) than dilute solution (1760 cm-1)?
EI-MS of ortho nitrotoluene shows a large fragment ion at m/z 120 .The EI-MS of Tri deuteron ortho nitrotoluene does not show any peak at m/z 120 but does have a peak at m/z 122 .Show the fragmentation pattern that accounts for the above observation.
Two compounds with partition coefficients of 15 and 18 are to be separated on a column with VSVM=0.30VSVM=0.30.  Calculate the number of theoretical plates needed to produce a resolution of 1.8. Do not worry about significant figures of your final answer.
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
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning
Text book image
Fundamentals Of Analytical Chemistry
Chemistry
ISBN:9781285640686
Author:Skoog
Publisher:Cengage