1. Chapter 8 Aromaticity Reactions of Benzene and Substituted Benzenes 1

2. The first structure for benzene was proposed by August Kekulé in 1872. 2

3. 3

4. We often represent benzene as a hybrid of two equivalent structures 4

5. To name a benzene ring with one substituent, name the substituent and add the word benzene. Naming Benzene Compounds 5

6. Common Names anisole toluene phenolaniline styrenebenzaldehydebenzoic acidbenzonitrile 6

7. ortho-dibromobenzene or o-dibromobenzene or 1,2-dibromobenzene meta-dibromobenzene or m-dibromobenzene or 1,3-dibromobenzene para-dibromobenzene or p-dibromobenzene or 1,4-dibromobenzene 7

8. If the two groups on the benzene ring are different, alphabetize the names of the substituents preceding the word benzene. If one substituent is part of a common root, name the molecule as a derivative of that monosubstituted benzene. 8

9. For three or more substituents on a benzene ring: 1.Number to give the lowest possible numbers around the ring. 2.Alphabetize the substituent names. 3.When substituents are part of common roots, name the molecule as a derivative of that monosubstituted benzene. The substituent that comprises the common root is located at C1. 9

10. 10

11. Name the following benzene compounds. 11

12. More practice….. Page 226 Problem 26 Page 214 Problem 14 12

13. More naming….. 13

14. Interesting Aromatic Compounds 14

15. 15

16. Reactions of Benzene: Oxidation 16

17. What are the products of oxidation of the following compounds? Another problem…..Page 213 Problem 12 17

18. Side Chain Bromination Reaction of an alkylbenzene with N-bromo-succinimide (NBS) and benzoyl peroxide (radical initiator) introduces Br into the side chain. 18

19. 19 Reduction of Aromatic Compounds

20. Reactions of Benzene: Electrophilic Substitution Vs Electrophilic Addition 20

21. Electrophilic Aromatic Substitution 21

22. 22

23. Halogenation 23

24. Nitration and Sulfonation 24

25. Friedel-Crafts Alkylation 25

26. Limitations of Friedel Crafts Reactions 26

27. Page 212 Problem 11 27

28. Friedel-Crafts Acylation 28

29. Di- and Polysubstitution Existing groups on a benzene ring influence further substitution in both orientation and rate Orientation  certain substituents direct new substitution preferentially toward ortho-para positions, others direct preferentially toward meta positions Rate  certain substituents are activating toward further substitution, others are deactivating toward further substitution 29

30. -OCH 3 is ortho-para directing Ortho-para Directors 30

31. Meta Directors 31

32. Types of Substituents 32

33. Page 218 Problem 18 33

34. Page 221 Problem 19 34

35. Trisubstituted Benzenes 35

36. 36

37. 37

38. Where would the electrophile attack the ring preferentially? 38

39. Predict the major product of each of the following reactions. 39

40. Synthesis of p-Bromobenzoic acid 40

41. The order of steps is important. 41