1. Spectroscopy: UV spectra MiniQuiz Conclusion Unknown 2/ Introduction Unknown 3: Nitro compounds. Inert Compounds. Today:

2. Nitro Compounds Typical properties? Classification test: Always do with a known compound to compare! Derivatives (if no other functional group available): Reduce to amine and then prepare amine derivatives Preliminary tests? Solubility Classification tests Derivatives Spectra Iron (II) Hydroxide Test for Nitro Groups Nitro Compounds

3. Carboxylic Acids IR: H-NMR: Preliminary tests? Solubility Classification tests Derivatives Spectra OH in gas phase (non-H-bonded)

4. Amines IR H-NMR Voodoo Lily Amorphophallus

5. Amides H-NMR : Preliminary tests? Solubility Classification tests Derivatives Spectra IR?

6. Unknown 3 can be “anything”: Any of the functional groups of unknowns 1 and 2; also “Inert compounds”

7. “Inert Compounds” Alkanes Aromatic Hydrocarbons Alkyl halides. Aryl halides. Chemical tests and derivatives depend on compound. Beilstein test (p.626) for Cl, Br Compare with known compound!

8. See Chapter in your Lecture text (conjugated systems)  to  * HOMO to LUMO  A =  x C x l A = absorbance;  = molar absorptivity C = concentration in mol/L; l = sample pathlength in cm UV/Visible Spectrophotometry Range of UV in nm? Which compounds generally absorb in the UV? CH 4 ? CH 3 (CH 2 ) 10 CH 3 ? Ethanol? Benzene? Naphtalene?  -Carotene? FeCl 3 ? Which compounds absorb in the visible range? CH 4 ? CH 3 (CH 2 ) 10 CH 3 ? Ethanol? Benzene? Naphtalene?  -Carotene? FeCl 3 ?

9. UV/Visible Spectrophotometry

11. max

12. Next time: Infrared spectrophotometry (IR) MiniQuiz on today’s class