1. LIMONENE

2. MYRCENE

3. LYCOPENE

4. BETA CAROTENE

5. CARYOPHYLLENE

6. GERANIOL

7. MENTHOL

8. ZINGIBERENE

9. UNSATURATED HYDROCARBON

10. UNSATURATED HYDROCARBON
Contain one or more carbon – carbon double, triple bonds and benzene ring in their structures.
The term “ UNSATURATION “ shows that there are fewer hydrogens attached to carbon than in ALKANE.

11. 3 family
ALKENE – An unsaturated hydrocarbon that contains one or more carbon – carbon double bonds.
ALKYNES – An unsaturated hydrocarbon that contains one or more carbon – carbon triple bonds.
AROMATIC – Organic compounds that contains the characteristics of benzene & benzene ring in its structure.

12. Physical Properties
The physical properties of unsaturated hydrocarbons are very similar to those of the corresponding saturated compounds. They are very slightly soluble in water.
Except for aromatic compounds, unsaturated hydrocarbons are highly reactive and undergo addition reactions to their multiple bonds. Typical reagents added are hydrogen halides, water, sulfuric acid, elemental halogens and alcohols.

13. ALKENES

14. Nomenclature of ALKENES

15. RULES ON NAMING ALKENES
RULE 1 : Number the carbon chain to give the lowest number to the double bond.
(be sure to use the longest carbon chain containing the double bond for the parent chain )

16. ethene
1 - propene 1 3 2 1 2 3 4
2 - butene

17. 5 – methyl – 3 – propyl – 2 – heptene
CH2 1 ║
CH3 – CH2 – C – CH2 – CH3 4 3 2
2 – ethyl – 1 – butene
CH3 – CH – CH2 – C – CH2 – CH2 – CH3 5 │ 4 3 ║
3HC2HC
CH – C H3 7 6 2 1
5 – methyl – 3 – propyl – 2 – heptene

18. RULES ON NAMING ALKENES
RULE 2 : If there are multiple double bonds in a structure we use the prefixes such as di, tri, tetra, penta, and so on……………….

19. CH2 ═ C – C ═ C – CH3 3HC CH3 CH3 CH3 3HC CH34 5 1 │ │ │
3HC
CH3
CH3
2,3,4 – trimethyl – 1,3 – pentadiene
CH3
3HC
CH3 │ │ │
CH2 ═ C – CH2 – C ═ C – CH – C ═ CH2 8 7 6 │ 5 4 3 │ 2 1
CH3CH2
CH2CH3
3,5 – diethyl – 2,4,7 – trimethyl – 1,4,7 – octatriene

20. RULES ON NAMING ALKENES
RULE 3 : If an ALKENE is a ring structure, place the prefix “cyclo” in front of the ALKENE name.

21. CYCLOPROPENE
1,3,5,7 – cyclooctatetraene
1,4 – cyclohexadiene

22. RULES ON NAMING ALKENES
RULE 4 : If CYCLOALKENE has a side groups or chain, the double bond is numbered as carbon 1 & 2 in the direction around the ring that gives the lowest numbers to the first branch…….

23. CH2CH3
3 – ethyl – 4 – methyl – 1 – cyclobutene Br
CH3 Br
1,2,4 – tribromo – 1,4 – cyclohexadiene Br
1 – chloro – 3,3 – difluoro – 1 - cyclopropene F Cl F

27. Physical Properties
The physical properties of alkenes are comparable with ALKANES. The PHYSICAL STATE depends on MOLECULAR MASS.
The simplest alkenes, ethylene, propylene and butylene are gases.
Linear alkenes of approximately five to sixteen carbons are liquids, and higher alkenes are waxy solids.

28. Chemical Properties
Alkenes are relatively stable compounds, but are more reactive than alkanes. This is compatible with the idea that the carbon-carbon double bond in alkenes is stronger than the carbon-carbon single bond in alkanes, however, as the majority of the reactions of alkenes involve the rupture of this bond to form two new single bonds.
A double bond is not as strong as a single bond, so it is more easily broken. This means that the alkenes are more chemically reactive than the alkanes.

29. Reactions

30. Addition Reaction
Is a type of chemical reaction in which a compound adds to a multiple bond.
In the case of addition reaction take place in ALKENES, one bond in the double bond is broken in order to form new bonds.

31. Types of Addition Reaction
Halogenation
Hydrogenation
Hydrohalogenation
Hydration
Polymerization

32. Halogenation
Is an addition reaction wherein unsaturated hydrocarbon specifically ALKENE reacts with halogens such as chlorine, bromine, fluorine, and iodine that produce haloalkane as a product.

33. General Formula of : Example : Halogenation Reaction: CH2 = CH2 + Cl2
Alkene +
Halogen →
Haloalkane
Example :
Cl – Cl
CH2 = CH2 +
Cl2
CH2Cl – CH2Cl →
ethene
1,2 - dichloroethane

34. Mechanism CH3 – CH – CH2 F – F ----------→ CH3 – CH = CH2 + F2 F F│ │
CH3 – CH – CH2
1,2 - difluoropropane

35. Industrial Application

36. Hydrogenation
Is an addition reaction wherein double bond adds hydrogen in the presence of transition metal catalyst such as platinum (Pt) and nickel (Ni) that yield to saturated hydrocarbon as product.

37. General Formula of : Example: Hydrogenation Reaction Alkene + Hydrogen
Pt/Ni
Alkene +
Hydrogen →
Alkane
Example:
H – H
Pt/Ni
CH2 = CH2 + H2 →
CH3 – CH3
ethane
ethene

38. Mechanism CH3 – CH2 – CH3 CH3 – CH = CH2 + H2 H – H PROPANEPt →
CH3 – CH = CH2 + H2
H – H
CH3 – CH2 – CH3
PROPANE

39. Industrial Application

42. HYDROHALOGENATION
Is an addition reaction wherein hydrogen halides such as hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen fluoride (HF) and hydrogen iodide (HI) is added to unsaturated sites that yield to halogenated hydrocarbon as product.

43. General Formula of : Example: ethene 1 - chloroethane
HYDROHALOGENATION REACTION
Alkene +
Hydrogen Halides →
Haloalkane
Example:
H – Cl →
CH2 = CH2 +
HCl
CH3 – CH2Cl
ethene
1 - chloroethane

44. Mechanism ethene CH2 – CH2 1 - chloroethane CH2 = CH2 + H – Cl Cl H │→
ethene Cl H │ │
CH2 – CH2
1 - chloroethane

45. Conditions under HYDROHALOGENATION REACTION
2 TYPES OF ALKENE STRUCTURE
SYMMETRICAL – Is an ALKENE structure having the same number of hydrogen atoms attached to both sides of the double bond.
UNSYMMETRICAL – Is an ALKENE structure having different numbers of hydrogen atoms attached to both sides of the double bond

46. Markovnikov ‘s Rule “ the rich get richer “
If the two carbon atoms at the double bond are linked to a different number of hydrogen atoms, the halogen will attach at the carbon with least number of hydrogen and hydrogen will attach at the carbon with more hydrogen attached to it.

47. Vladimir Markovnikov Russian chemist College Professor
University of Kazan in St. Petersburg
Director of the Chemistry Institute
1869
He gave rise to rule for predicting w/c product will be exclusively or predominantly formed.

48. Actual Reaction H Br Br H CH2 – CH – CH3 CH2 – CH – CH3 10 % 90 %+
H – Br → H Br Br H │ │ │ │
CH2 – CH – CH3 or
CH2 – CH – CH3 1 2 3 1 2 3
1 - bromopropane
2 - bromopropane
10 %
90 %

49. Examples H Cl 2 - chlorobutane CH3 – CH – CH – CH3 -----------→+
H – Cl → H Cl
2 - chlorobutane │ │ 1
CH3 – CH – CH – CH3 4 3 2 →
CH3 – CH2 – CH = CH2 +
H – Cl
2 - chlorobutane Cl H │ │
90 %
CH3 – CH2 – CH – CH2 4 3 2 1

50. Industrial Application

51. HYDRATION
Is an addition reaction in which the components of water, H – and OH, bond to the carbon – carbon double bond in the presence of strong acid catalyst such as sulfuric acid to form an alcohol.

52. General Formula of : Example: HYDRATION REACTION Alkene ------------→
H2SO4
Alkene →
Alcohol +
Water
Example:
H2SO4
CH2 = CH2 +
H – O H →
CH3 – CH2OH
ethyl alcohol
ethene

53. Mechanism CH3 – CH – CH2 -----------→ CH3 – CH = CH2 + H – OH
H2SO4 →
CH3 – CH = CH2 +
H – OH
1 - propene OH H │ │
CH3 – CH – CH2
2 - propanol
(Isopropyl alcohol)

54. Industrial Application

55. POLYMERIZATION

56. A REACTION THAT PRODUCES A POLYMER………
POLYMERIZATION
A REACTION THAT PRODUCES A POLYMER………
Polymerization - Is the single most important reaction of alkenes it is an economically important reaction which yields polymers of high industrial value, such as the plastics polyethylene and polypropylene

57. Addition Polymerization
A reaction in which monomer units are joined together to form a polymer without loss of atoms.

58. MONOMER
From the Greek, meaning single part; a small building block from which a polymer is derived.
single part; (mono + meros).
The starting material that becomes the repeating units of polymer.

59. Polymer Name & Common Uses
Monomer Formula
Common Name
Polymer Name & Common Uses
CH2 ═ CH2
ethylene
Polyethylene, polythene; containers & packaging materials.
CH2 ═ CHCH3
propylene
Polypropylene, herculon; textile and carpet fibers.
CH2 ═ CHCl
Vinyl chloride
Poly (vinyl chloride), PVC; construction tubing.
CH2 ═ CCl2
1,1 dichloroethylene
Poly (1,1 – dichloroethylene), Saran; food packaging.
CH2 ═ CHCN
acrylonitrile
Polyacrylonitrile, Orlon; acrylics and acrylates.
CF2 ═ CF2
Tetrafluoroethylene
Polytetrafluoroethylene, Teflon; nonstick coatings.
CH2 ═ CHC6H5
styrene
Polystyrene, Stryrofoam; insulating materials.
CH2 ═ CHCO2CH2CH3
Ethyl acrylate
Poly (ethyl acrylate); latex paint.
CH2 ═ CCO2CH3 │
CH3
Methy methacrylate
Poly (methyl methacrylate), Lucite, Plexiglass; glass substitute.

60. POLYMER
From Greek, meaning many parts; a large molecule built up from bonding together of smaller units called monomer.
Many part (poly + meros).
A very large molecule made up of repeating units.

61. 2 Types of Polymer
ADDITION POLYMER – A polymer formed by the linking together of many alkene molecules through addition reactions.
COPOLYMER – An addition polymer formed by the reaction of two different monomers.

62. 3 steps in POLYMERIZATION
Step 1 : Chain Initiation – formation of radicals from non – radical molecules.
Example :
NOTE: LDPE (500°C/1000 atm & Peroxides catalyst)
TiCl3/Al(CH2 – CH3)3
------→
In·
CH2 ═ CH2
In – CH2 – CH2· +
60°C/20atm
Alkyl radical

63. Step 2 : Chain Propagation
Is a reaction of a radical and a molecule of monomer.
Propagation steps generally repeat over and over (propagate) with the radical formed in one step reacting with a monomer to produce a new radical, and so on.
Chain propagation steps can continue until all starting materials are consumed.
The number of times a cycle of chain propagation steps repeats is called CHAIN LENGTH.

64. Example In – CH2 CH2· + CH2 ═ CH2 In – CH2CH2CH2CH2· ------→
monomer
radical
In – CH2CH2CH2CH2·
------→
Chain length

65. Step 3 : Chain Termination
The characteristic feature of a chain termination step is coupling of radicals to form a compound with an even number of electrons.
Note : polymerization of ethylene, chain lengthening reaction occur at a very rapid rate, often as fast as thousand of addition per second, depending on the experimental conditions.

66. Polymer (Polyethylene)
Example :
~ CH2CH2·
·CH2CH2 ~ + →
~ CH2CH2 – CH2 CH2 ~
Polymer (Polyethylene)

67. PET Polyethylene Terephthalate
Two-liter beverage bottles, mouthwash bottles, boil-in-bag pouches. 1

69. HDPE High Density Polyethylene
Milk jugs, trash bags, detergent bottles.

71. PVC Polyvinyl Chloride
Cooking oil bottles, packaging around meat, pipes, plastic tiles.

73. Low Density Polyethylene
Grocery bags, produce bags, food wrap, bread bags.

75. PP  Polypropylene
Yogurt containers, shampoo bottles, straws, margarine tubs, diapers.

77. PS  Polystyrene 
Hot beverage cups, take-home boxes, egg cartons, meat trays, cd cases.

79. OTHER
All other types of plastics or packaging made from more than one type of plastic.