1. AROMATIC SUBSTITUTION REACTIONS REACTIONS

2. NOMENCLATURE

3. Learn Nomeclature Either on Your Own Learn Nomeclature Either on Your Own or Use the Organic Nomeclature Software methylbenzene 1-chloro-3-methylbenzene (toluene) 1-bromo-3-nitrobenzene 1,4-dimethylbenzene

4. SOME SPECIAL NAMES tolueneanilineanisole o-xylenem-xylene p-xylene phenol benzoic acid

5. ipso ortho meta para ortho, meta and para Positions m-nitrotoluene 3-nitrotoluene 1-methyl-3-nitrobenzene o- m- p- 1 2 3 4 5 6 p-dichlorobenzene 1,4-dichlorobenzene

7. Compounds containing aromatic rings are often used in dyes, such as these for sale in a market in Nepal Source: Getty Images

8. REVIEW OF BENZENE PROPERTIES

9. Figure 22.11: The structure of benzene

10. BENZENE RESONANCE Review Sections 6.8 - 6.14 KEKULE STRUCTURES Resonance Energy = 36 Kcal / mole All bonds are equivalent The ring is symmetric. Bond lengths are between a single and a double bond. Very Stable Less reactive than other groupings of atoms.

11. H H HH H H...... All 2p orbitals overlap equally.

12. BENZENE Isodensity surfaces - electron potential mapped in color. (van der Waal ’ s) Color adjusted to enhance the pi system. Highest electron density is red. Note the symmetry.

13. cyclohexatriene (hypothetical) benzene cyclohexene cyclohexane RESONANCE ENERGY 36 kcal/mol -85.8 kcal/mol (calculated) -28.6 kcal/mol -49.8 kcal/mol BENZENE - DETERMINATION OF RESONANCE ENERGY

14. REACTIVITY

15. The “ Double Bonds ” in a Benzene Ring Do Not React Like Others AlkeneBenzene ++ no reaction ++ no reaction + + no reaction + + no reaction

16. + + Stronger base Weaker base Readily donates electrons to an electrophile. Donation of electrons would interrupt ring resonance (36 kcal / mole). A strong electrophile is required - and often a catalyst. Benzene is a Weak Base and Poor Nucleophile alkene benzene

17. Benzene requires a strong electrophile and a catalyst …..and then it undergoes substitution reactions, not addition. + + Benzene Reactivity substitution catalyst + compare: addition no catalyst

18. Some Substitution Reactions of Benzene + + + + + Halogenation Friedel-Crafts Alkylation Friedel-Crafts Acylation Nitration Sulfonation ++ - -

21. Blood Alcohol Level

22. Alcohols and Water alcohols are “monosubstituted” water, ROH, hydrocarbon radical, R, substituted for one of the hydrogen atoms in water, HOH alcohols form hydrogen bonds to other alcohol molecules, increasing boiling point, and to water, making them very soluble in water

23. Classes of Alcohols

24. Oxidation of Alcohols primary alcohol  aldehyde  carboxylic acids RCH 2 OH  RCHO  RCOOH secondary alcohols  ketones RCHOHR’  RC=OR’ tertiary alcohols  No Reaction

25. Large Molecules Containing Alcohol Groups

26. More Large Molecules Containing Alcohol Groups

27. Ethanol is being tested in selected areas as a fuel for automobiles Source: AP/Wide World Photos

28. ALDEHYDES AND KETONES I

29. Aldehyde Ketone STRUCTURE

30. Cinnamaldehyde produces the characteristic odor of cinnamon Source: Visuals Unlimited

31. NOMENCLATURE

32. Choose the longest continuous carbon chain that contains the carbonyl carbon Number from the end of the chain closest to the carbonyl carbon Ketone ending is -one IUPAC Nomenclature of Ketones Do the ketones section of Organic Nomenclature program!

33. 2-Pentanone EXAMPLES 4-Ethyl-3-hexanone

34. 3-Isopropylcyclopentanone or 3-(1-Methylethyl)cyclopentanone

35. Common, or Trivial, Names Name each group attached to the carbonyl group as an alkyl group Combine into a name, according to the pattern: alkyl alkyl ’ ketone NOTE: This is not all one word! KETONES

36. Methyl propyl ketone Example of Common Names Diethyl ketone

37. acetone dimethyl ketone A common laboratory solvent and cleaning agent SPECIAL CASES benzophenone diphenyl ketone acetophenone methyl phenyl ketone KNOW THESE

38. Choose the longest continuous carbon chain that contains the carbonyl carbon Number from the end of the chain closest to the carbonyl carbon (carbon #1!) Aldehyde ending is -al IUPAC Nomenclature of Aldehydes Do the aldehydes section of Organic Nomenclature program.

39. EXAMPLES pentanal 2-chloro-3-methylbutanal 1 2 3 4 always carbon 1 aldehyde group is

40. Common Names of the Aldehydes RECOGNIZE THESE

41. SPECIAL CASES formaldehyde acetaldehyde benzaldehyde KNOW THESE

42. Figure 22.13: Some common ketones and akdehydes

44. Figure 22.14: Some carboxylic acids

45. Computer-generated space-filling model of acetylsalicylic acid (aspirin) Source: Photo Researchers, Inc.