Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
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Question
Chapter 15.SE, Problem 46AP
Interpretation Introduction
Interpretation:
Given that 1-phenyl-2-butene has an ultraviolet absorption at λmax = 208nm (∈ = 8000). On treatment with a small amount of strong acid it isomerizes to give a new compound with λmax = 250nm (∈ = 15,800). A structure for the isomer is to be proposed and a mechanism for its formation has to be suggested.
Concept introduction:
Among two isomers with same molecular formula, the isomer that has extended conjugation will have a higher λmax value than the other.
To propose:
A structure for the isomer which has an ultraviolet absorption at λmax = 250 nm (∈ = 15,800) obtained when 1-phenyl-2-butene with λmax = 208 nm (∈ = 8000) is treated with strong acids. Further to propose a mechanism for its formation.
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Chapter 15 Solutions
Organic Chemistry
Ch. 15.1 - Prob. 1PCh. 15.1 - Give IUPAC names for the following compounds:Ch. 15.1 - Prob. 3PCh. 15.2 - Pyridine is a flat, hexagonal molecule with bond...Ch. 15.3 - Prob. 5PCh. 15.4 - Draw the five resonance structures of the...Ch. 15.4 - Prob. 7PCh. 15.4 - Prob. 8PCh. 15.5 - Prob. 9PCh. 15.5 - Prob. 10P
Ch. 15.6 - Prob. 11PCh. 15.6 - How many electrons does each of the four nitrogen...Ch. 15.SE - Give IUPAC names for the following substances (red...Ch. 15.SE - All-cis cyclodecapentaene is a stable molecule...Ch. 15.SE - 1, 6-Methanonaphthalene has an interesting 1H NMR...Ch. 15.SE - Prob. 16VCCh. 15.SE - Azulene, an isomer of naphthalene, has a...Ch. 15.SE - Give IUPAC names for the following compounds:Ch. 15.SE - Draw structures corresponding to the following...Ch. 15.SE - Prob. 20APCh. 15.SE - Prob. 21APCh. 15.SE - Draw and name all possible aromatic compounds with...Ch. 15.SE - Propose structures for aromatic hydrocarbons that...Ch. 15.SE - Look at the three resonance structures of...Ch. 15.SE - Prob. 25APCh. 15.SE - Prob. 26APCh. 15.SE - Look at the five resonance structures for...Ch. 15.SE - Prob. 28APCh. 15.SE - 3-Chlorocyclopropene, on treatment with AgBF4,...Ch. 15.SE - Prob. 30APCh. 15.SE - Prob. 31APCh. 15.SE - Prob. 32APCh. 15.SE - Which would you expect to be most stable,...Ch. 15.SE - How might you convert 1, 3, 5, 7-cyclononatetraene...Ch. 15.SE - Calicene, like azulene (Problem 15-17), has an...Ch. 15.SE - Pentalene is a most elusive molecule that has been...Ch. 15.SE - Prob. 37APCh. 15.SE - Prob. 38APCh. 15.SE - Compound A, C8H10, yields three substitution...Ch. 15.SE - Prob. 40APCh. 15.SE - Propose structures for compounds that fit the...Ch. 15.SE - Prob. 42APCh. 15.SE - Prob. 43APCh. 15.SE - N-Phenylsydnone, so-named because it was first...Ch. 15.SE - Prob. 45APCh. 15.SE - Prob. 46APCh. 15.SE - Prob. 47APCh. 15.SE - Propose a structure for a molecule C14H12 that has...Ch. 15.SE - The proton NMR spectrum for a compound with...Ch. 15.SE - The proton NMR spectrum of a compound with formula...Ch. 15.SE - Aromatic substitution reactions occur by addition...Ch. 15.SE - Prob. 52APCh. 15.SE - Consider the aromatic anions below and their...Ch. 15.SE - After the reaction below, the chemical shift of Ha...Ch. 15.SE - Prob. 55APCh. 15.SE - Azo dyes are the major source of artificial color...
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