3.10 Aromatics Flashcards
Name these aromatic compounds
Name these aromatic compounds
What is meant by
a) aliphatic
b) aromatic or arene
a) straight or branched chain organic substances
b) includes one or more ring of six carbon atoms with delocalised bonding
Describe bonding in benzene
Each carbon has three covalent bonds
Spare electrons in a p orbital overlap to form a Pi cloud
Delocalisation occurs
Describe shape of benzene
Planar
6 carbon rings - bond angle of 120 degrees
C-C bonds are equal in length
For nitration of benzene, state
* Reagents
* Mechanism
* Electrophile
* Overall reaction of reagents
Reagents = Conc H2SO4 & Conc HNO3
Mechanism = Electtrophilic substitution
Electrophile = NO2 ^+
Reaction = H2SO4 + HNO3 –> HSO4^- + H2O + NO2 ^+
Draw electrophilic substitution mechanism (nitration of benzene)
For friedel crafts acylation mechanism, state
* Reagents
* Conditions
* Mechanism
* Eqaution for formation of electrophile
* Overall eqaution for reaction
Reagents = acyl chloride and catalyst AlCl3
Condition = heat under reflux
Mechanism = Electtrophilic substitution
Eqaution for formation of electrophile = AlCl3 + CH3COCl –> [CH3CO]^+ + [AlCl4]^-
Draw mechanism of acyl chloride reacting with benzene
Fur reducing a nitroarene to aromatic Amines
State
* Reagent
* Conditions
* Mechanism
* Write overall reaction eqaution
Effect of delocalisation on side groups with lone pairs
What is the role of sulfuric acid in the nitration of benzene?
Catalyst
What is the electrophile that generates C6H5COCH3?
CH3CO+
