synthesis !

Question 1

alkanes

Answer 1

free radical substitution

UV light

Question 2

alkene

Answer 2

1. hydrogenation
   add H2
   nickel catalyst
   alkane formed
2. steam hydration
   add H2O(g)
   acid catalyst e.g. H3PO4
   alcohol formed
3. electrophilic addition
   halogens
   dihaloalkane formed

Question 3

alcohol

Answer 3

1. substitution
   compound containing halide ions e.g. NaBr
   acid catalyst H2SO4
   haloalkane formed
2. dehydration
   acid catalyst. H2SO4 or H3PO4 and heat
   alkene formed
3. oxidation (Orange -> green!)
   acidified potassium dichromate. Cr2O72-
   primary alcohol -> aldehyde -> carboxylic acid
   secondary alcohol -> ketone

Question 4

haloalkane

Answer 4

1. nucleophilic substitution
   aq alkali e.g. NaOH
   or water (slower)
   alcohol
2. nucleophilic substitution
   heat
   reagents haloalkane. excess of ethanolic ammonia
   make aliphatic amine
3. nucleophilic substitution
   reflux with K/NaCN in ethanol
   forms nitrile (C2H5CN)

Question 5

benzene

Answer 5

1. electrophilic substitution
   nitration
   reagent conc HNO3
   catalyst conc H2SO4
2. electrophillic substitution
   add Br2/Cl2
   catalyst halogen carrier AlBr3 or FeBr3
3. friedel crafts
   reagent haloalkane e.g. CH3Cl
   catalyst halogen carrier

4.Acylation of benzene (C6H5COCH3)
reagent acyl chloride RCOCl
catalyst halogen carrier AlCl3

Question 6

phenol

Answer 6

1. carbonate
   doesn’t react - weak acid
2. strong base e.g. NaOH
   neutralisation e.g. C6H5O-Na+ and water
3. electrophillic substitution with bromine
   triple substitution 2,4,6-tribromophenol

4.electrophilic substitution with dilute nitric acid
2-nitrophenol

Question 7

carbonyls

Answer 7

1. oxidation of aldehyde
   Cr2O7 2- / H+
   forms COOH
2. nucleophilic substitution
   NaBH4 (supplies H-) and then addition of water
   formation of alcohol
3. nucleophilic addition
   HCN
   forms hydroxynitrile

Question 8

amines

Answer 8

1. neutralised by acid
   form ammonium salt

2.making

Question 9

aromatic compount

Answer 9

1. reduce nitro compound e.g. nitrobenzene
   add tin and concentrated HCl (reflux) then add NaOH
   form aromatic amine

Question 10

amino acids

Answer 10

1. COOH reacts with alkalis
   forms salt and water
2. NH2 reacts with acids
   forms salt and
3. reacts with alcohol
   catalyst strong acid H2SO4
   ester

Question 11

nitrile

Answer 11

1. reduced
   LiAlH4 followed by dilute acid OR ethanol and Na. in industry H2 and platinum or nickel catalyst
   to form primary amine
2. hydrolyse
   reflux in dilute HCl
   form carboxylic acid