Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Chapter 30.SE, Problem 35AP
Interpretation Introduction
Interpretation:
Ring opening reaction of the trans-cyclobutene isomer shown takes place readily at a lower temperature than a similar ring opening of the cis-cyclobutene isomer. This temperature effect is to be explained and the stereochemistry of each reaction, conrotatory or disrotatory, is to be identified.
Concept introduction:
An electrocyclic reaction involves the cyclization of a conjugated acyclic system. These reactions are reversible and are highly stereospecific.
In elecrocyclic reactions involving even number of electron pairs, a thermal reaction occurs in conrotatory manner and a photochemical reaction occurs in disrotatory manner.
In elecrocyclic reactions involving odd number of electron pairs, a thermal reaction occurs in disrotatory manner and a photochemical reaction occurs in conrotatory manner.
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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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