6.2.4 Carbon-carbon Bond Formation

Question 1

what are some of the different reactions that involve formation of C-C bond

Answer 1

nucleophilic substitution of haloalkanes with cyanide ions
addition of hydrogen cyanide to form hydroxynitriles
preparing amines from nitriles
preparing carboxylic acids from nitriles
friedel crafts alkylation
friedel crafts acylation

Question 2

nucleophilic substitution of haloalkanes with cyanide ions

Answer 2

haloalkane -> nitrile
reagent: KCN dissolved in ethanol/water mixture
conditions: heat under reflux
mechanism: nucleophilic substitution 
type of reagent: nucleophile, CN-

Question 3

what does the nucleophilic substitution of a haloalkane with cyanide ions d o

Answer 3

increases the length of the carbon chain

Question 4

how do you name a nitrile

Answer 4

nitrile group must be at the end of the chain
start from numbering chain at the C with the CN
“butanenitrile”

Question 5

addition of hydrogen cyanide to carbonyls to form hydroxynitriles

Answer 5

carbonyl -> hydroxynitrile

reagent: sodium cyanide and dilute sulfuric acid
conditions: room temperature and pressure
mechanism: nucleophilic addition

Question 6

what do the NaCN and H2SO4 provide in the addition of hydrogen cyanide reaction

Answer 6

CN- ions and H+ ions

needed in the second step of the mechanism

Question 7

why not HCN

Answer 7

toxic gas that is difficult to contain

KCN and NaCN are toxic due to the cyanide ion

Question 8

preparing amines from nitriles

Answer 8

reduce nitrile to amine

LiAlH4 in ether or reducing with H2 using nickel catalyst

Question 9

preparing carboxylic acids from nitriles

Answer 9

hydrolysing nitriles by reacting them with strong acids will produce a carboxylic acid
hydrolysis reaction

Question 10

friedel crafts alkylation

Answer 10

benzene -> alkylbenzene

reagents: chloroalkane in the presence of anhydrous aluminium chloride catalyst
conditions: heat under reflux
mechanism: electrophilic substitution

Question 11

friedel crafts acylation

Answer 11

benzene -> phenyl ketone
reagents: acyl chloride in presence of anhydrous aluminium chloride catalyst
conditions: heat under reflux (50 degrees)
mechanism : electrophilic substitution