Chapter 17: Alcohols and Phenols - PowerPoint PPT Presentation

lethia
chapter 17 alcohols and phenols n.
Skip this Video
Loading SlideShow in 5 Seconds..
Chapter 17: Alcohols and Phenols PowerPoint Presentation
Download Presentation
Chapter 17: Alcohols and Phenols

play fullscreen
1 / 78
Download Presentation
Chapter 17: Alcohols and Phenols
228 Views
Download Presentation

Chapter 17: Alcohols and Phenols

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Chapter 17: Alcohols and Phenols Dr. Sivappa Rasapalli Chemistry and Biochemistry University of Massachusetts Dartmouth

  2. Coverage and Objectives • Coverage: • 1. Structure and Bonding; Physical Properties of Alcohols • 2. Acidity of Alcohols and Phenols • Formation of Alkoxides and Phenoxides • Preparation of Alcohols including Review Reactions • and Ring-opening Reactions of Epoxides (+ Mechanisms). • 5. Reactions of Alcohols + Mechanisms • Objectives: • 1. Know all mechanisms discussed in class. • Know how to predict the relative acidities of substituted alcohols and phenols. • Know reactions and reagents for preparation of alcohols including review reactions. • Know reactions of alcohols and mechanisms.

  3. Alcohols and Phenols

  4. CO + 2H2 CH3OH Oldest known synthesis: fermentation Sugar + yeast  ethyl alcohol + CO2

  5. Role of Hydroxy group in Antitumor Agents

  6. Problem 1: Classify each of the following either as a phenol, or as a 1º, 2º, 3º, or vinyl alcohol

  7. IUPAC Rules for Naming Alcohols 3-hydroxycyclohexanone

  8. Nomenclature of Phenols Problem 2: Name the following using IUPAC system

  9. Structure and Bonding of Alcohols

  10. 17.2 Physical Properties: miscible miscible 0.6% soluble

  11. Acidity of Alcohols and Phenols

  12. Acidity of Alcohols

  13. Acidity of Phenols

  14. Acidity of Phenols Summary of EDG/EWG Substituents on p-Bonding Systems • donating and withdrawing ability measured relative to hydrogen

  15. Problem 3: Write the products of the following reactions

  16. Preparation of Alcohols: an Overview

  17. Retrosynthesis R R C O H OH C H H R R H:– H OH C O C R' R' H:–

  18. Oxidation-Reduction Reactions in Organic Chemistry

  19. Alcohols by Reduction of Carbonyl Compounds

  20. Reducing agents i-Butyl H H – + – + H H H Li Na H H Al Al B H iButyl H Lithiumaluminum hydride Diisobutylaluminum hydride both reagents act as donors of hydride (H-) donors Sodiumborohydride

  21. Sodium borohydride Aldehydes are reduced to 1° alcohols Ketones are reduced to 2° alcohols The reagent adds the equivalent of hydride to the carbon of C=O and polarizes the group as well

  22. NaBH4 Vs LiAlH4 synthons precursors = NaBH4 reduces aldehydes to primary alcohols NaBH4 reduces ketones to secondary alcohols NaBH4 does not react with esters or carboxylic acids

  23. NaBH4 Vs LiAlH4

  24. Preparation of Diols

  25. Preparation of Diols

  26. Recap of the reduction and examples

  27. Alcohols via Grignard

  28. Grignard reactions

  29. Grignard reaction of Aldehydes and Ketones

  30. Mechanism

  31. Organometallics

  32. Order of the reactivity

  33. Grignard + Ester • Grignard attacks the carbonyl and OEt ion leaves. Ketone intermediate

  34. Grignard + Acid Chloride • Grignard attacks the carbonyl and Chloride ion leaves. Ketone intermediate

  35. How would you synthesize... • Using an aldehyde or ketone. Using an acid chloride or ester.

  36. Grignard with epoxides

  37. Draw the mechanism and the products for the following?

  38. Problems

  39. Propose a synthetic route

  40. Grignard Reagents and Other Functional Groups in the Same Molecule • Which Solvents (if any) Would be OK for Handling RMgBr?, • Which substrates could be converted into RMgBr, and Subsequently reacted with CH3CHO?

  41. Combining Grignard Reactions with Other Reactions

  42. Some Reactions of Alcohols Two general classes of reaction • At the carbon of the C–O bond • At the proton of the O–H bond

  43. Dehydration of Alcohols

  44. Conversion to halides

  45. Solve the following?

  46. Tosylates are Pseudohalides!