1. Reference Information Unless otherwise noted, all mass spectral data was obtained from: National Institute of Standards and Technology (NIST) Standard Reference Database at webbook.nist.gov/chemistry/ Slide 16 image: Integrated Spectral Data Base System for Organic Compounds at www.aist.go.jp/RIODB/SDBS/menu-e Webspectra at www.chem.ucla.edu/~webspectra/ The picture on slide 4 was obtained from:

2. Analytical Chemistry Chromatography (Separations) Mass Spectrometry Infrared (IR) Spectroscopy Nuclear Magnetic Resonance (NMR) Spectroscopy X-ray Crystallography (visual solid state molecular structure)

3. Mass Spectrometry What insights are we hoping to gain? Molecular Mass/Isotopic Distribution Molecular Formula Some Structural Characteristics – Fragmentation Pattern

4. Only molecules of the correct m/z (mass/charge) will make it to the detector.

5. EI-MS of 2,2-Dimethyl Pentane

6. Peaks with smaller m/z values __ called fragment ion peaks __ represent positively charged fragments of the parent molecule

7. EI-MS of 2,2-Dimethyl Pentane

8. EI-MS of n-Propanol

9. EI-MS of 4-Heptanone

12. Isotopes

13. EI-MS of Benzyl Bromide

14. Isotopes

15. EI-MS of Benzyl Bromide

16. EI-MS of 4-Chloroanisole

17. Isotopes

19. What about Identical Masses?

20. Exact Mass