Reaction of anthracene

1. UNIT-4
Pharmaceutical Organic Chemistry-II
Seven Hills College Of Pharmacy

2. Reactions Of Naphthalene
• Oxidation Reactions
• Reduction reactions
• Addition Reactions
• Electrophilic substitution reactions
Nitration
Halogenation
Friedel-Crafts Alkylation
Sulfonation
Friedel-Crafts Acylation

3. Oxidation Reactions
COOH
COOH
COOH
COOH
O
O
O
CHO
CHO
O
O
O
KMno4
Acidic medium
KMno4
Basic medium
Chronic acid
O3,Zn/H2O
Ozonolysis
H2SO4
HgSO4
Phthalic acid
Phthalonic acid
1,4-Napthaquinone
Phthaladehyde
Phthalic anhydride
Napthalene

4. Reduction reactions
H2/Ni
H2/Pt
Napthalene
H
H
H
H
Na
Isopentanol
Na-C2H5OH
H2/Ni
Tetralin
Decalin
(Trans)
1,4-Dihydrodialin
Decalin
(cis)
Tetralin

5. Addition Reactions
X
H
H X
H X
H
X
H
X
H X
+X2
X=Cl,Br
Napthalene 1,4-dihalo addition 1,2,3,4-Tetrahaloaddition
+X2

6. Electrophilic substitution reactions
NO2 NH2
OH
Cl
Naphthalene
1-Nitronaphthalene 1-Naphthylamine 1-Naphthol
1-Chloronaphthalene
HNO3 Fe/HCL H2O/H+
PCL5
Nitration
Nitration Halogenation Friedel-Crafts Alkylation
Friedel-Crafts Acylation Sulfonation

7. Br
Cl
Naphthalene
1-Bromonaphthalene 1-Chloronaphthalene
Br2,Fe
CCl4
Cl2
Fe
Halogenation Friedel-Crafts
Alkylation
CH3
Naphthalene
AlCl3
CH3CH2Br
AlCl3
CH3
C2H5
CH3I
1-Methylnaphthalene
(Major)
1-Methylnaphthalene
(Minor)
2-Methylnaphthalene
(Minor)

8. COCH3
Naphthalene
CH3COCl,AlCl3
CS2
C6H5NO2
COCH3
Non-polar solvent
CH3COCl,AlCl3
Polar solvent
Methyl-1-Napthyl ketone Methyl-2-Napthyl ketone
SO3H
Naphthalene
SO3H
Naphthalene-2-Sulfomic acid
Naphthalene-1-Sulfomic acid
<800 >1200
Sulfonation
Friedel-Crafts Acylation

9. Anthracene(C14H10)
• Anthracene is composed of three fused benzene rings.
• It is colourless solid show blue fluorescence in UV light
• It is a component of coal tar. All carbon atoms are sp2
hybridized and ring has 14 pi electrons.
1
2
3
4
5
6
7
8 9
10

10. Synthesis of Anthracene
1. Friedel-Crafts reaction.
From Haworth synthesis
From Benzyl chloride
From Benzene Methylene Dibromide.
2. Elbs Reation
3. Diels-Alder Reaction

11. When Phthalic anhydride in benzene solution is reacted with AlCl3 O-Benzoyl
benzoic acid is formed. This on heating with Conc,H2So4 Yield
anthraquinones which on distillation with Zinc dust give Anthracene
Haworth synthesis
From Benzyl chloride
Anthracene was prepared by condensation of two molecules of benzyl
chloride in presence of AlCl3.
CH2Cl
AlCl3
-2HCl
Bnzyl chloride Anthracene
2
O
HOOC
+
O
O
O
AlCl3
O
O
Zn dust
H2SO4
Benzene Phthalic anhydride 2-Benzoyl benzoic acd Anthraquinone
Anthracene
1. Friedel-Crafts reaction.

12. From Benzene Methylene Dibromide:
Anthracene can also prepared by reaction of benzene with methylene dibromide in
the presence of AlCl3
Anthracene may be synthesised by Diels Alder reaction involving 1,4-napthoquinone
and butadiene followed by oxidation of product with chromium trioxide in glacial
acetic acid and distillation with Zn dust.
2. Diels Alder reaction:
2 2 CH2B2
+
-2H
AlCl3
Benzene Methylene dibromide Anthracene
O
O
O
O
O
O
+
1,4-Napthaquinone
Butadiene
CrO3
Zn
Anthracene
SnCl4
-500
C
9,10 Anthraquinone

13. 3.Elbs Reaction:
A diaryl ketone containing a methyl group ortho to the carbonyl group E.g: o-methyl
benzophenone on pyrolysis gives anthracene
H3C
O
Pyrolysis
-H2O
O-Methyl Benzophenone
Anthracene

14. Reactions of Anthracene
• Electrophilic substitution reaction
• Other reactions
Oxidation, Reduction, dimerization.

15. Electrophilic substitution reactions
X
X2/CS2
X=Cl,Br
9-haloanthracene
SO3H
SO3H
Anthracene-1-sulphonic acid Anthracene-2-sulphonic acid
+
H2SO4
HNO3
(CH3CO)2O
NO2
9-Nitroanthracene
COCH3
COCH3
SO3H
HO3S
SO3H
SO3H
CH3COCL,AlCl3
Non-polar solvent
CH3COCL,AlCl3
polar solvent
9-acetyl anthracene
1-acetylanthracene
anthracene-2,7-disulfonic acid
anthracene-1,8-disulfonic acid
High tem
Low tem
Anthracene

16. Other reactions X
X=Cl,Br
9,10-dihaloanthracene
Oxidation
Reduction
Na/C2H5OH
9,10-dihydroanthracenea
Anthracene
X
X2
O
Reduction
H2/Ni
Perhydroanthracene
O
Dianthracene
Dimerization
UV
Anthraquinone
Na2Cr2O7

17. Phenanthrene
• Colourless crystal obtained from coal tar.
• Its solution in benzene shows fluorescecne and is very reactive
in 9,10 positions.
• Carbons in Phenanthrene are SP2 hybridized and have 14 pi
electrons.
• It is isomeric with anthracene.
1
2
3
4
5
6
7
8
9 10
1
2
3
4
5
6
7
8 9
10

18. Synthesis of Phenanthrene
1. Haworth synthesis
2. Pschorr synthesis

19. 1. Haworth synthesis
+ O
O
O
O
HOOC
HOOC
O
Naphthalene
Succinic
anhydride
3(1-napthoyl)prpionic acid
4(1-napthyl)butanoic
acid
Cyclic ketone
Zn-Hg
Pd-C
H2SO4
Zn-Hg
AlCl3
Phenanthrene

20. 2.Pschorr synthesis
NaOOCH2C
CHO
NO2
+ (CH3CO)2O
HC C
COOH
NO2
HC C
COOH
N2
+
HSO4
HC C
COOH
NaNO2/
H2SO4
Cu
H2SO4
-CO2
H2SO4
O-Nitrobenzaldehyde