Q4. The following is the ¹3C NMR spectrum of a highly concentrated solution of dicyclopentadiene obtained in chloroform-d. Despite the high purity of the compound based on ¹H NMR, there is a massive peak observed at 77.2 ppm in this 13C spectrum, which doesn't correspond to any resonances expected for dicyclopentadiene. What is this peak, and why do you not see a corresponding peak for this compound in your ¹H NMR spectrum? <-136.22 132.62 222E- 132.23 135 130 125 120 115 110 105 100 95 85 80 75 70 65 60 10'55- · 55 <-50.56 50 45 40 35 wwwww 30

Q4. The following is the ¹3C NMR spectrum of a highly concentrated solution of dicyclopentadiene obtained in chloroform-d. Despite the high purity of the compound based on ¹H NMR, there is a massive peak observed at 77.2 ppm in this 13C spectrum, which doesn't correspond to any resonances expected for dicyclopentadiene. What is this peak, and why do you not see a corresponding peak for this compound in your ¹H NMR spectrum? <-136.22 132.62 222E- 132.23 135 130 125 120 115 110 105 100 95 85 80 75 70 65 60 10'55- · 55 <-50.56 50 45 40 35 wwwww 30

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter21: Benzene And The Concept Of Aromaticity

Section: Chapter Questions

Problem 21.20P

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Dr. N. M. Arr was called in to help analyze the 1H NMR spectrum of a mixture of compounds known to contain only C, H, and Br. The mixture showed two singlets—one at 1.8 ppm and the other at 2.7 ppm—with relative integrals of 1 : 6, respectively. Dr. Arr determined that the spectrum was that of a mixture of bromomethane and 2-bromo-2-methylpropane. What was the ratio of bromomethane to 2-bromo-2-methylpropane in the mixture?
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