1 / 54

Reactions of Alcohols

Reactions of Alcohols. Oxidation R-X, Ether, and Ester Preparation Protection of Alcohols Synthesis The Logic of Mechanisms. Alcohols are Synthetically Versatile. Oxidation levels of oxygen- halogen- and nitrogen- containing molecules. Oxidation - Reduction.

latimer
Download Presentation

Reactions of Alcohols

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. Reactions of Alcohols Oxidation R-X, Ether, and Ester Preparation Protection of Alcohols Synthesis The Logic of Mechanisms

  2. Alcohols are Synthetically Versatile

  3. Oxidation levels of oxygen- halogen- and nitrogen-containing molecules

  4. Oxidation -Reduction

  5. Oxidation of 2o Alcohols with Cr(VI)

  6. Mechanism

  7. Oxidation of 1o Alcohols

  8. PCC oxidizes 1o Alcohols to Aldehydes

  9. Oxidation of 1o Alcohols to Aldehydes: PCC

  10. Swern Oxidation

  11. Oxidation Summary

  12. Reduction Summary

  13. Conversion of Alcohol into a Leaving Group • Form Tosylate (p-TsCl, pyridine) • Use strong acid (H3O+) • Convert to Alkyl Halide (HX, SOCl2, PBr3)

  14. Formation of p-Toluenesulfonate Esters

  15. Best to use p-TsClwith pyridine

  16. Reactions of Tosylates:Reduction, Substitution, Elimination

  17. Alcohols to Alkyl Halides

  18. SN1: Carbocations can Rearrange

  19. Lucas Test

  20. Qualitative test for Alcohol Characterization

  21. Other Simple Qualitative Tests

  22. 1o and 2o Alcohols: best to use SOCl2, PBr3,or P/I2

  23. Thionyl chloride mechanism in Pyridine –SN2, Inversion

  24. Thionyl chloride mechanism in Dioxane –2 SN2,Retention

  25. Dehydration of Alcohols – E1

  26. Methide Shift is Faster than Loss of H+

  27. Dimerization of Alcohols:Symmetrical Ethers

  28. Mechanism

  29. Williamson Ether SynthesisPreparation of Unsymmetrical Ethers

  30. Mechanism, SN2

  31. Protection of Alcohols

  32. Alcohol is acidic enough to react preferentially.

  33. Chlorotrimethylsilane (TMS-Cl)

  34. Mechanism is SN2

  35. Protect as trimethylsilyl ether

  36. Give the Reagents…

  37. No Protection needed

  38. Synthesize using cyclohexane, 2-butanol and methanol

  39. Determine Where New Bonds are Formed

  40. Synthesis problem 11-57 (Wade)

  41. Retrosynthesis to alcohols

  42. Retrosynthetic Analysis

  43. Work back to 3 Alcohols

  44. Synthesis

  45. Provide a sequence of steps

  46. Mechanisms Thinking Logically • Do not use reagents that are not given. • Is the product a result of a rearrangement? Only intermediates can rearrange. • Is one of the reagents H3O+? If so, use it in the 1st step. Do not create negatively charged species in acid.

More Related