Chapter 17: Alcohols and Phenols

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

6. Role of Hydroxy group in Antitumor Agents

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

8. IUPAC Rules for Naming Alcohols 3-hydroxycyclohexanone

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

10. Structure and Bonding of Alcohols

11. 17.2 Physical Properties: miscible miscible 0.6% soluble

12. Acidity of Alcohols and Phenols

13. Acidity of Alcohols

14. Acidity of Phenols

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

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

17. Preparation of Alcohols: an Overview

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

19. Oxidation-Reduction Reactions in Organic Chemistry

20. Alcohols by Reduction of Carbonyl Compounds

21. 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

22. 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

23. 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

24. NaBH4 Vs LiAlH4

25. Preparation of Diols

26. Preparation of Diols

27. Recap of the reduction and examples

29. Alcohols via Grignard

30. Grignard reactions

31. Grignard reaction of Aldehydes and Ketones

32. Mechanism

33. Organometallics

35. Order of the reactivity

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

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

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

39. Grignard with epoxides

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

41. Problems

42. Propose a synthetic route

43. 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?

44. Combining Grignard Reactions with Other Reactions

45. 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

46. Dehydration of Alcohols

47. Conversion to halides

48. Solve the following?

49. Tosylates are Pseudohalides!