Topic 22-Aromatic chemistry Flashcards
Benzene structure
-Planar Cyclic structure
- Has rings of delocalised electrons
- Length of bonds is between double and single bond
Why is benzene stable?
It has delocalised pi bonds
Aromatic compounds which use benzene naming
Chlorobenzene
Nitrobenzene
1,3 Dimethyl Benzene
Aromatic compounds which use phenyl
Phenol
Phenylamine
Conditions for nitration
50degrees
Benzene
Sulfuric and Nitric acid
Uses of nitration reactions
dyes and pharmeceuticals
Equation for the production of electrophile
(Nitration)
2H2SO4 + HNO3 –> NO2+ 2HSO4- + H3O+
Equation for the production of electrophile
(Acylation)
CH3COCl + AlCl3 –> AlCl4- + Ch3CO+
Regeneration of the catalyst
(Acylation)
AlCl4- + H+ –> AlCl3 + HCl
Reagents and conditions for Friedel Craft’s Acylation
Reagents: Acyl chloride
Catalyst: AlCl3
Conditons: anhydrous to prevent reaction of AlCl3
What can nitration of aromatic compounds be used for
Manufacture of explosives
Formation of amines
What used to hydrogenate benzene
Nickel catalyst and hydrogen
How was kekule structure disproven
Bond length different from both C-C and C=C
Hydrogenation of benzene was less exothermic than expected
Didnt react with Br2 as expected
Why dont electrophiles undergo reactions with benzene under standard conditions?
Would destroy stable ring of delocalised electrons
Why wont chlorobenzene react with nucleohpiles
Area of high electron density repels nucleophiles