1. Organic Chemistry CE 541

2. Aromatic Hydrocarbons They are hydrocarbons that include benzene and compounds containing aliphatic or aromatic groups attached to aromatic rings. Benzene is the simplest aromatic hydrocarbon (C6H6)

3. More recently, the following is used to represent the structure of Benzene

4. Nomenclature The monocyclic aromatic hydrocarbons are named as derivatives of the parent benzene. Trivial names of some of the compounds are still recognized by the IUPAC T olueneo-xylenem-xylenep-xylene T olueneo-xylenem-xylenep-xylene (ortho-xylene)(meta-xylene)(para-xylene)

5. In the IUPAC system, aromatic compounds with one group attached to them are named by combining the name of the group with benzene. All these structures are named as Chlorobenzene, and all represent the same compound.

6. There are three different ISOMERIC compounds with two substituents on the ring. The positions of the substituents on these compounds are indicated as follows: ortho (or 1, 2 - ) meta (1, 3 - )para (or 1, 4 - ) ortho (or 1, 2 - ) meta (1, 3 - )para (or 1, 4 - ) abbreviated o- abbreviated m-abbreviated p- abbreviated o- abbreviated m-abbreviated p-

7. Using benzene or toluene as parent structure, the following examples illustrate the use of the system o-dichlorobenzenem-dichlorobenzene p-dichlorobenzene o-dichlorobenzenem-dichlorobenzene p-dichlorobenzene o-chlorotoluenem-chlorotoluene p-chlorotoluene o-chlorotoluenem-chlorotoluene p-chlorotoluene

8. For compounds with three or more substituents on the ring, we must use numbers to indicate the position on the ring and apply the following rules: 1. The parent structure is benzene or toluene 2. For benzene, the group name written next to the word “benzene” becomes position number 1 on the ring and the ring is numbered in a direction that will give the lowest possible numbers to the substituents. 3. For toluene, the methyl group becomes position number 1 on the ring and the ring is numbered in a direction that will give the lowest possible numbers to the substituents. The number 1 position is assumed in both benzene and toluene derivatives, but is not indicated in the name. 4. All groups are placed in alphabetical order except the group in the number 1 position.

9. Examples (a)Iodobenzene(b)m-dinitrobenzene (c) p-nitrobromobenzene (d) 4 – bromo – 2 - nitrotoluene

10. (e) 2, 5 – dibromo – 3 nitrotoluene

11. Hydrocarbons 1. Benzene Series BenzeneC6H6 BenzeneC6H6 TolueneC6H5 + CH3 TolueneC6H5 + CH3 XyleneC6H4 (CH3)2 XyleneC6H4 (CH3)2 EthylbenzeneC6H5 + C2H5 EthylbenzeneC6H5 + C2H5 They : Are used extensively as solvents Are used extensively as solvents Are insoluble in water (relatively) Are insoluble in water (relatively) Are common constituents of petroleum products Are common constituents of petroleum products Cause cancers to human Cause cancers to human

12. Styrene is a benzene derivative used in the production of polystyrene products Styrene

13. 2. Polyring Hydrocarbons (a) Naphthalene (C10 H8) (b) Anthracene (C14 H10)

14. (c) Phenanthrene (C14H10)

15. Chlorinated Aromatic Hydrocarbon (1) Chlorinated Benzenes They are benzene with one or more of the hydrogen are replaced by chlorine (2) Polychlorinated Biphenyls (PCBs) They are chlorinated benzenes with the following general structure: X can be H or Cl X can be H or Cl There are 209 possible PCBs There are 209 possible PCBs Stable compounds (some can be biodegraded) Stable compounds (some can be biodegraded) Used widely as coolants in transformers, solvents, and hydraulic fluids Used widely as coolants in transformers, solvents, and hydraulic fluids Bio-concentrate Bio-concentrate

16. Derivatives of the Hydrocarbons 1. Organic Halides Examples DDT (dichlorodiphenyltrichloroethane) DDT (dichlorodiphenyltrichloroethane) Chlorofluorocarbons (CFC, CF2Cl2, CFCl3) Chlorofluorocarbons (CFC, CF2Cl2, CFCl3) Organic Halides Alkyl halides Alkyl group attached to a halogen atom such as F, Cl, Ba, I. General formula: R – X R = alkyl group X = halogen atom Aryl halides Halogen atom attached to an aromatic ring. General formula: Ar – X Ar = Aromatic ring X = halogen atom

17. Nomenclature

20. Nomenclature

22. Examples

24. Classifications of Alcohols

27. Common Alcohols

28. Chemical Reactions of Alcohols

34. Nomenclature

36. Examples

40. Nomenclature

41. Examples

45. Nomenclature Trivial names of few aldehydes are accepted by IUPAC system. These names are derived from the corresponding carboxylic acids by replacing the – ic of the acid by -aldehyde

48. Examples

51. Common Aldehydes

55. Nomenclature (1) If both groups attached to the carbonyl group are alkyl groups, they are named as follows: Name the alkyl groups attached to the carbonyl group. If both groups are the same, the prefix -di is used Name the alkyl groups attached to the carbonyl group. If both groups are the same, the prefix -di is used Add the word “ketone” Add the word “ketone”

56. Examples

59. to name compounds as phenones, the follwing should be done: Name the cyl group as given above Name the cyl group as given above Add phenone to the name of the acyl group Add phenone to the name of the acyl group

60. Examples

62. Example

64. Ketones are prepared by oxidation of secondary alcohol

67. Nomenclature

68. Examples

72. Nomenclature (1) The systematic IUPAC of the acid is used. (2) Replace –ic by –ate.

73. Examples

76. Nomenclature (1) when trivial names of carboxylic acids are used, the –ic acid part of the name is replaced by the ending –amide (i.e. the amide of acetic acid is acetamide) (2) the IUPAC name is obtained by dropping the –oic acid ending of the IUPAC name of the acid and replacing it with the ending –amide.

77. Examples

80. Nomenclature

83. Examples

85. Cyclic Aliphatic Compounds

87. Heterocyclic Compounds

89. Food and Related Compounds

95. Fats, Oils and Waxes

97. Proteins and Amino Acids

108. Fate of Organics (Table 5-14)