Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Question
Chapter 30.SE, Problem 33AP
Interpretation Introduction
Interpretation:
The stereochemistry, suprafacial or antarafacial, expected for the photochemical [1,5] sigmatropic rearrangement reaction is to be stated.
Concept introduction:
Sigmatropic rearrangements involve the migration of a σ bond present at the end or in the middle of the system across the π electron system from one position to another. They are represented by [m,n] where m and n represents the number of atoms between the bond being broken and the bond being formed in two directions.
If even number of electron pair is involved then thermal reaction occur through antarafacial pathway and photochemical reactions occur through suprafacial pathway.
If odd number of electron pair is involved then thermal reaction occur through suprafacial pathway and photochemical reactions occur through antarafacial pathway.
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Students have asked these similar questions
a) What product is formed from the [1,7] sigmatropic rearrangement of a deuterium in the following triene? (b) Does this reaction proceed in a suprafacial or antarafacial manner under thermal conditions? (c) Does this reaction proceed in a suprafacial or antarafacial manner under photochemical conditions?
Which of the following describes the sigmatropic rearrangement that occurs in the
reaction shown below?
CH2
CH3
dede
CH3
CH₂
[3,3] sigmatropic rearrangement
[2,3] sigmatropic rearrangement
[1,4] sigmatropic rearrangement
[1,3] sigmatropic rearrangement
[1,5] sigmatropic rearrangement
Classify each reaction as an electrocyclic reaction, a cycloaddition, or a sigmatropic rearrangement. Label the σ bonds that are broken or formed in each reaction
Chapter 30 Solutions
Organic Chemistry
Ch. 30.1 - Prob. 1PCh. 30.3 - Prob. 2PCh. 30.3 - Prob. 3PCh. 30.4 - Prob. 4PCh. 30.6 - What stereochemistry would you expect for the...Ch. 30.6 - Prob. 6PCh. 30.7 - Prob. 7PCh. 30.8 - Propose a mechanism to account for the fact that...Ch. 30.8 - When a 2, 6-disubstituted allyl phenyl ether is...Ch. 30.9 - Prob. 10P
Ch. 30.SE - Predict the product obtained when the following...Ch. 30.SE - Prob. 12VCCh. 30.SE - The following rearrangement of N-allyl-N,...Ch. 30.SE - Plastic photochromic sunglasses are based on the...Ch. 30.SE - Prob. 15MPCh. 30.SE - Prob. 16MPCh. 30.SE - Prob. 17MPCh. 30.SE - Prob. 18APCh. 30.SE - Prob. 19APCh. 30.SE - Prob. 20APCh. 30.SE - Prob. 21APCh. 30.SE - Prob. 22APCh. 30.SE - Prob. 23APCh. 30.SE - Prob. 24APCh. 30.SE - Prob. 25APCh. 30.SE - Prob. 26APCh. 30.SE - Prob. 27APCh. 30.SE - Prob. 28APCh. 30.SE - Propose a pericyclic mechanism to account for the...Ch. 30.SE - Prob. 30APCh. 30.SE - Prob. 31APCh. 30.SE - Prob. 32APCh. 30.SE - Prob. 33APCh. 30.SE - Bicyclohexadiene, also known as Dewar benzene, is...Ch. 30.SE - Prob. 35APCh. 30.SE - Prob. 36APCh. 30.SE - The 1H NMR spectrum of bullvalene at 100 C...Ch. 30.SE - Prob. 38APCh. 30.SE - Prob. 39APCh. 30.SE - Prob. 40APCh. 30.SE - In light of your answer to Problem 30-40, explain...
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