Organic ChemistryOrganic Chemistry

AlkenesOne double bond

Unsaturated hydrocarbons (carbons are NOT holding the maximum number of

hydrogen atoms they can hold)

C4H8

1. Common name

-ylene

C8H16

CH2 CH2

Alkyl group

C CH

H

HThe Vinyl group

C CH

H

H

CH2The Allyl group

C CH

H

H

Br……………..

C CH

H

H

CH2 Cl ………………….

AlkenesAlkenes1.2. Ethene C2H4

3. Propene C3H6

4. Butene C4H8

5. Pentene C5H10

6. Hexene C6H12

7. Heptene C7H14

8. Octene C8H16

9. Nonene C9H18

10.Decene C10H20

CnH2n

…..ene

2. IUPAC name

IUPAC name

C CCH2CH3

H

H3C

H

IUPAC name

C C

H

H

H

CH2CH3

C C

H

H3C

Br

CH2CH3

C C

H

Cl

F

Br

1. Cis 3-Heptene

Draw the structure and give the molecular formula for each of the following compounds.

2. Cis Cyclohexene

3. trans-Cyclohexene

Physical Properties of Alkenes

H2C CH2

H3C CH3

H3C CH2 CH3

H2C CH2 CH3

-86.6

-103.7

-42.1

-47.7

bpFormular

Cycloalkenes CnH2n-2 (n=3,4,5,…)

C4H8

Isomer

C4H8

Isomer

Isomer

C5H10

Reactions of Alkenes

1.Combustion reaction

C5H10 + O2

C8H16 + O2

2. Addition Reactions

A characteristic reaction of compounds with a carbons-carbon double bond is a addition.

-Hydrogenation reaction

-Halogenation reaction (X2 / CCl4 )

-Hydrohalogenation reaction (HBr, HCl)

-Hydration reaction (H2O)

Reactive intermediated in organic chemistry

c

C

c

c

H

c C

H

H

c C

H

H

H CC

High LOW

2. Addition reaction

-Hydrogenation reaction

(H2) Ni, Pd, Pt cat.

-Halogenation reaction (X2 / CCl4 )