17.4 2 Some Reactions Of Benzene

Question 1

Hydrogenation

Answer 1

Mix benzene with hydrogen and heating under pressure with a nickel catalyst
Get cyclohexane

Question 2

Combustion

Answer 2

Burns with a smoky flame due to high carbon to hydrogen ratio

Question 3

Bromination

Answer 3

Substitution reaction
Benzene and bromine heated under reflux in presence of a catalyst called a halogen carrier
Swap H for a br
Bromobenzene and HBr

Question 4

Halogen carrier

Answer 4

Metal-halogen compound
Aluminium chloride or bromide
Iron (111) bromide

Question 5

Nitration

Answer 5

Substitution of H for nitro group
Nitro = NO2 (isn’t the gas)
Warm benzene with a mixture of concentrated nitric acid and sulfuric acid which is the catalyst
Nitrobenzene and water

Question 6

Friendless-Crafts reactions

Answer 6

Use reagent XY where one of the hydrogen atoms is substituted by Y and other product is HX
Catalyst is need often aluminium chloride
Anhydrous conditions are needed as water reacts with the catalyst and sometimes also the organic product

Alkylation and acylation two need to know

Question 7

Alkylation reactions

Answer 7

Substitution of one of the hydrogen atoms for an alkyl group
Reagent is halogenoalkane products akylbenzene and hydrogen halogen

Question 8

Acylation reactions

Answer 8

Substitution of one of the hydrogen atoms by an acyl group

Reagent an acyl chloride and products are a ketone (phenylethanone ) and hydrogen chloride

Question 9

See

Answer 9

Book for structures

Question 10

Halogen carrier definition

Answer 10

Catalyst that helps introduce a halogen atom into a benzene ring