Foundations in Organic Chemistry

1. Foundations inOrganic Chemistry Combined Spectroscopy A tutorial created by: Eric J. Kantorowski, Ph.D. California Polytechnic State University Version 2.0

2. Combined Spectroscopy Problems • The following pages contain examples of interpreting 1H NMR and 13C NMR spectra • Try solving each structure • Successively pressing the spacebar will reveal analyses of the spectra leading you toward the structure

3. 6H Is most likely attached to EN element or electron-withdrawing group 2H Impossible! 1H This adds up to 5 C’s Only three signals in 13C NMR; therefore there must be symmetry Two carbons must be equivalent

4. C5H9Br CH2 CH2 equivalent to C5H10 C5 C5H12 CH IHD = 1 (1 ring or 1 p bond) Alkene C’s would appear here 1 ring!

5. 6H C6H12O2 Total = C5H12 3H 2H 1H Still missing 1 C and 2 O IHD = 1

6. Press any key to reveal the structure 3H 1H 1H 2H

7. Press any key to reveal the structure 5H 2H 2H

8. Press any key to reveal the structure 2H Disappears on addition of D2O 1H 1H 2H 2H

9. Press any key to reveal the structure

10. Press any key to reveal the structure 1H 2H 2H

11. Press any key to reveal the structure 6H 1H 1H

12. cholesterol These spectra are provided just for the sake of showing how spectral interpretation of complex structures can be a daunting task. Indeed, more advanced methods are required to elucidate a structure such as cholesterol.

13. Brevetoxin B Imagine the complexity of the 1H NMR of the tremendously beautiful structure of Brevetoxin B…