3.10 - Aromatic Chemistry Flashcards
Compounds containing Benzene Rings are Called?
Arenes
Name of Mechanism: Benzene + Electrophile
Electrophilic Substitution
Reagents: Acylation of Benzene
Acyl Chloride
AlCl₃
Conditions: Nitration of Benzene
50°C
Evidence against Kekule’s Structure?
- Doesn’t Decolourise Bromine Water
- Carbon-Carbon bonds are intermediate in length between single & double bonds
- Thermochemical data of Hydrogenation of Benzebe is ∼150kJmol⁻¹ more stable
Uses of Nitrobenzene?
Explosives
What do Double-headed curly arrows show?
Movement of a Pair of Electrons
Why does Benzene undergo Substitution rather than Addition?
To Preserve stability of Delocalised electrons in π-bond
Where is the Break in the Benzene ring located when it has a Positive charge?
Break faces Carbon which Electrophile is being Attached to
Benzene is ____, it has a ____ ____ structure with bond angles of ____ ?
Planar
Trigonal Planar
120°
Overlap of adjacent p-orbitals forms a ____ above & below ring?
π-bond
The Electron Density in ____ is lower than in ____ ?
Benzene
an Alkene
Carbon-Carbon bonds in ____ are ____ in length between ____ ?
Benzene
Intermediate
Single & Double Bonds
Electrons in the π-bond are ____ ?
Delocalised
The π-bond above & below the ring is an area of ____ ____ ____ that attracts ____ ?
High Electron Density
Electrophiles
In Benzene, the π-electrons are ____ in an alkene, they’re ____ ?
Delocalised
Localised
In ____, π-electrons are localised in ____, they’re delocalised?
an Alkene
Benzene
Kekule’s Structure of Benzene?
Cyclohextriene
Benzene is ____ reactive than methylbenzene?
Less
If Benzene contained ____ bonds, it would ____ ____ water?
Carbon-Carbon double bonds
Decolourise Bromine Water
Electrophile: Nitration of Benzene
NO₂⁺
Define: Electrophile
Electron Pair Acceptor
Generation of Electrophile: Nitration of Benzene
HNO₃ + H₂SO₄ |> NO₂⁺ + HSO₄⁻ + H₂O
The ____ ____ in an Alkene is ____ than in Benzene?
Electron Density
Higher
Electrophile: Acylation of Benzene
R-C(=O)⁺
Conditions: Reduction of Nitrobenzene
Reflux
Reagents: Nitration of Benzene
conc. HNO₃
conc. H₂SO₄
Reagents: Reduction of Nitrobenzene
Tin & conc. HCl
Conditions: Acylation of Benzene
Anhydrous
Uses of Aminobenzene?
Dyes, Pharmaceuticals
Why is Methylbenzene more reactive than Benzene?
Methyl group has a Positive Inductive effect
∴ Electron Density is Higher
Reacts more readily with Electrophiles
Thermochemical data of ____ of Benzene is ____ more stable?
Hydrogenation
∼150kJmol⁻¹
Mr of Benzene?
78