1 / 14

Help Needed! at ACS Family Science Night at Oak Grove Middle School, Concord

See Poster TH 7 th floor hallway!. Help Needed! at ACS Family Science Night at Oak Grove Middle School, Concord Wednesday, Oct.22, 6 - 9 pm. What would you do? Help set up experiments Help middle school students (and their parents) do the experiments. What would you get?

tala
Download Presentation

Help Needed! at ACS Family Science Night at Oak Grove Middle School, Concord

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. See Poster TH 7th floor hallway! Help Needed!atACSFamily Science Night at Oak Grove Middle School, Concord Wednesday, Oct.22, 6 - 9 pm • What would you do? • Help set up experiments • Help middle school students (and their parents) do the experiments • What would you get? • experience in working with youngsters and showing them the fun of science (chemistry!) • a nice entry on your resume • a good impression with your instructor! Please email msequin@sfsu.edu if you can help! It’s fun!

  2. Smells and Molecules

  3. Today: • Diels-Alder (cont.) • Esterification (Exp.5) a first introduction D.-A. adduct

  4. Diels – Alder Reactions (Exp.4) Diels-Alder reactions are another example of syntheses that introduce additional C – C bonds to a reactant. Which structural feature is always formed as the result of Diels-Alder reactions? Diels-Alder reactions are what type of reactions? A cyclohexene ring. A stereospecific reaction, s-cis addition

  5. Diels – Alder Reactions The Diels-Alder reaction requires a 1,3-diene and a dienophile. 1,3-diene in s-cis conformation Dienophile: alkene, most reactive if EWG is attached

  6. Diels – Alder Reactions The Diels-Alder reaction requires a 1,3-diene (in s-cis) and a dienophile (alkene, best with EWG attached). Reaction equations for our experiment: Retro Diels Alder:Cracking of dimer Diels Alder: Reaction of 1,3-cyclopentadiene with maleic anhydride Hydrolysis of Diels-Alder product Dimer D.-A. adduct Cis endo • Compare: • Polarity of I versus II • Mp. of I versus II

  7. Diels – Alder Reactions Which of the following dienes would be most reactive? why? 1,3-cyclopentadiene, 1,3-butadiene (see problems on Report Form) Which of the following dienophiles would be more reactive? Ethene or maleic anhydride

  8. Diels – Alder Reactions Synthesis of Natural Products D C A B Steroids

  9. CH3 CH3 D C CH3 CH3 A B HO Cholesterol

  10. Diels Alder The H-NMR of the dimer of 1,3-cyclopentadiene is quite complex, with many signals. In contrast, the proton NMR of our Diels-Alder product is simple, with few signals; the same is true for its hydrolysis product. How can you explain this?

  11. Methyl Benzoate Synthesis You will heat your reaction under reflux for 1 hour! Do Practice Problems, calculations … • In order to increase the yield of the ester, which of the following would help? • use an excess of methanol • use an excess of conc. sulfuric acid • Calculations …! Why sulfuric acid and not HCl?

  12. Esters and Esterifications • General properties of esters? • Compare the boiling points of carboxylic acids and esters of similar molecular weight and explain. • Examples of esters in biological systems? • Fats and Oils • Waxes • Ripening process in fruits • phosphate esters in DNA

  13. Salicin and Aspirin Salicin in willow bark (Salix)

  14. Next time: Conclusion of “Esterification” (Exp. 5) Grignard reactions (Exp. 6)

More Related