H 3 c c c c c ch 3 kekulé benzene dewar benzene

This preview shows 3 out of 6 pages.

H 3 C C C C C CH 3 Kekulé benzene Dewar benzene Prismane Fulvene 2,4-Hexadiyne NMR data C 6 H 6 isomer (a) 1 H-NMR: 7.3 ppm (singlet). 13 C-NMR: 128 ppm (doublet). (b) 1 H-NMR: 2.3 ppm (singlet). 13 C-NMR: 31 ppm (doublet). (c) 1 H-NMR: 6.2 ppm (multiplet; integral = 1), 6.5 ppm (multiplet; integral = 1), and 5.9 ppm (multiplet; integral = 1). 13 C-NMR data: 153 ppm (singlet), 134 ppm (doublet), 125 ppm (doublet), and 123 ppm (triplet). (d) 1 H-NMR: 1.8 ppm (singlet). 13 C-NMR: 72 ppm (singlet), 65 ppm (singlet) and 4 ppm (quartet). (e) 1 H-NMR: 6.0 ppm (multiplet; integral = 2) and 3.3 ppm (multiplet; integral = 1). 13 C-NMR: 139 ppm (doublet) and 33 ppm (doublet). 10. (2) Circle the one molecule that is the best fit for the following 1 H-NMR spectrum: 3.6 ppm (triplet; integral = 1), 3.5 ppm (triplet; integral = 1), 3.4 ppm (triplet; integral = 1), 3.3 ppm (singlet; integral = 1.5), 1.5 ppm (sextet; integral =1), and 0.9 ppm (triplet; integral = 1.5). OCH 3 O O O O OH H 3 CO O O 1715 cm -1 O ??? cm -1 11. (2) The carbonyl bond stretching frequency for acetone is 1715 cm -1 . The best estimate for the carbonyl stretching frequency of molecule C is (circle one): 1740 cm -1 1715 cm -1 1695 cm -1 Cannot determine Acetone Molecule C
Image of page 3

Subscribe to view the full document.

Chemistry 14C Winter 2011 Exam 2 Page 4 Page 4 score = O O 12. (6) Consider these molecules: Molecule D Molecule E How could spectroscopy be used to differentiate between these molecules? For each spectroscopic method listed below, write one precise, very specific, and brief ( no more than twenty words ) explanation of what you would allow you to differentiate between the products. If the method cannot differentiate write "cannot tell". Example answer: Mass spectrometry - The mass spectrum of molecule D has 626 peaks whereas the mass spectrum of molecule E has 947 peaks. Mass spectrum ( no more than twenty words ) : Infrared spectrum ( no more than twenty words ) : 1 H-NMR spectrum ( no more than twenty words ) :
Image of page 4
Chemistry 14C Winter 2011 Exam 2 Page 5 Page 5 score = 13. (34) Deduce the structure that corresponds to the spectral data on pages 5–7. Write your final answer in the box. A
Image of page 5

Subscribe to view the full document.

Image of page 6
You've reached the end of this preview.
  • Spring '06
  • Scerri
  • Chemistry, ppm, base peak

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern