Organic 14: Organic synthesis Flashcards
Draw the aliphatic organic synthesis map.
How do you make an alkyl hydrogensulfate from an alkene?
Electrophilic addition with concentrated H2SO4
How do you make an alcohol from an alkene?
Electrophilic addition with H2O and strong acid (e.g. H2SO4 or H3PO4)
How do you make a halogenoalkane from an alkene?
Electrophilic addition with aqueous halogen (e.g. bromine water)
How do you make a halogenoalkane from an alkane?
Free radical substitution
UV light needed to break bond between halogen atoms to form free radicals
How do you make an amine from a halogenoalkane?
Nucleophilic substitution with warm, ethanolic ammonia (in excess)
Two step reaction where NH3+ forms, then a second ammonia molecule gains the extra proton to form NH4+
How do you make a nitrile from a halogenoalkane?
Nucleophilic substitution with warm ethanolic KOH
How do you make an alcohol from a halogenoalkane?
Nucleophilic substitution with warm aqueous KOH or NaOH
How do you make an alkene from a halogenoalkane?
Elimination with warm ethanolic KOH or NaOH
How do you make an amine from a nitrile?
Reduction using nickel/hydrogen catalyst
R-CN + 2H2 –> RCH2NH2
How do you make an amide from an amine?
Nucleophilic addition/eliminiation
With acyl chloride or acid anhydride
How do you make an alkene from an alcohol?
Elimination (dehydration) with excess hot concentrated H2SO4
OR
passing alcohol vapours over heated Al2O3
How do you make an ester from an alcohol?
Esterification
Alcohol + carboxylic acid –> ester + water
With strong acid catalyst
Reversible reaction, forms an equilbrium mixture
How do you make an aldehyde from an alcohol?
Oxidation of a primary alcohol e.g. ethanol
Alcohol in excess
Heat then distill off product
K2Cr2O7 + H2SO4 (acidified potassium dichromate)
1y alcohol + [O] –> aldehyde + water
How do you make a ketone from an alcohol?
Oxidation of a secondary alcohol
e.g. propan-2-ol
K2Cr2O7 + H2SO4 (acidified potassium dichromate)
2y alcohol + [O] –> ketone + water
How do you make an alcohol from an aldehyde?
Reduction (nucleophilic addition)
Aldehyde + 2[H] –> 1y alcohol
with aqueous NaBH4 (acts as a source of hydride ions, while water provides H+)
How do you make a carboxylic acid from an aldehyde?
Oxidation
K2Cr2O7 + H2SO4 (acidified potassium dichromate)
or using Tollen’s reagent or Fehling’s solution
Aldehyde + [O] –> Carboxylic acid
How do you make an alcohol from a ketone?
Reduction (nucleophilic addition)
Ketone + 2[H] –> 2y alcohol
with aqueous NaBH4 (acts as a source of hydride ions, while water provides H+)
How do you make a hydroxynitrile from an aldehyde or ketone?
Nucleophilic addition with aqueous KCN followed by dilute acid
CN- ions used as nucleophiles, H+ ions supplied by acid
How do you make an ester from a carboxylic acid?
Esterification
Alcohol + carboxylic acid –> ester + water
With strong acid catalyst
Reversible reaction, forms an equilbrium mixture
What is a nucleophile?
A lone pair donor
What is an electrophile?
A lone pair acceptor
How do you make nitrobenzene from benzene?
Nitration (electrophilic substitution)
Warm concentrated HNO3 and H2SO4
Formation of electrophile:
H2SO4 + HNO3 –> HSO4- + H2O + NO2+
How do you make phenylamine from nitrobenzene?
Reduction
Tin and concentrated hydrochloric acid
Tin and hydrochloric acid react to form hydrogen, which reduces the nitrobenzene by removing oxygen atoms on the NO2 group and replacing them with hydrogen
Nitrobenzene + 6[H] –> Phenylamine + 2H2O
How do you make a phenylamide from phenylamine?
Nucleophilic addition/elimination
Using acyl chloride
