organic synthesis

• reduction of aldehyde/ketone to alcohol

  • reagent; NaBH4
  • conditions; in methanol and water
• oxidation

  • K2Cr2O7
  • H2SO4
• nitrile to amine

  • reduction
  • aqueous alcohol
  • step 1) react with aqueous KCN to form a nitrile
  • step 2) oxidise with H2 and a Ni catalyst
• NO2 to NH2

  • reduction
  • reagants ; Sn and HCl or Ni and H2
• nucleophilic addition

  • inorganic reagant; NaBH4
• acylation

  • acyl chloride (eg. CH3COCl)
  • condition; AlCl3 catalyst
• uses of phenylamine?

  • making dyes
  • making fabric softeners
  • making detergents
• distinguish between ammonia and methyamine?

  • measure their PH’s with a meter
  • methyl-amine is a stronger base and so will have a higher PH than NH3
• reducing benzene to cyclohexane?

  • H2 with a Ni catalyst
• bond angles between carbons in benzene vs cyclohexane?

  • benzene= 120°
  • cyclohexane= 109.5°
• why might a product turn out to be optically inactive?

  there is a planar c=o bond in the starting material, this is susceptible to an attack from either side by a 50:50 chance, this means that a racemic mixture is formed
• what compounds do nucleophilic addition elimination reactions with primary amines produce?

  N-substituted amines
• disadvantage and advantage of using a racemate in medicine?

  • advantage; cheaper medicine due to difficulty of separation
  • disadvantage; there may be unwanted side effects from one enantiomer
• what functional group?

  acid amide

  
• ethene to ethane?

  • H2 with a Ni catalyst
• alkane to nitrile conditions and reagants?

  • KCN
  • aqueous & ethanolic
• what are the uses of quaternary ammonium salts?

  • making fabric softener
  • making detergent
  • making bactericide
• catalytic cracking?

  catalyst; zeolite

  conditions; moderate pressure
• give 2 ways to maximise yield of product during the distillation of an alcohol?

  • keep the temperature below the boiling point of the alcohol to ensure that it remains a liquid
  • cool the distillate to prevent evaporation
• explain the shape and bonding in a benzene molecule?

  • each carbon has three bonds with the spare electrons, forming a pi cloud
  • benzene is a planar and hexagonal shape, with each c-c being equal in length
• why is chloroethanoic acid a stronger acid than ethanoic acid?

  • the chlorine atom has a negative inductive effect
  • this weakens the O-H bond in the carboxyl group
• why chlorethanoic acid is stronger than ethanoic? (FURTHER)

  • as the chlorine atom withdraws electron from the -COOH region, the O atom in the O-H bond struggles to hold onto the shared pair of electrons, causing the H+ atom to dissociate more easily
• how does carbon dioxide contribute to global warming ?

  the C=O bond in CO2 is polar and so absorbs IR radiation, this means that the IR radiation emitted by earth does not escape
• why is ethanoyl chloride not used in industrial synthesis?

  it forms strong HCl fumes
• why may a species not be biodegradable?

  the c-c bonds are non-polar
• • during the hydrolysis of an amide under acidic conditions, the amide is broken down into a carboxylic acid and a protonated amine, so NH3+
  • the amine group is protonated because of the excess H+ from the acid used
• why might an enzyme be able to breakdown one enantiomer and not the other?

  • the enzyme has a highly specific active site
  • the enantiomer has the correct complementary shape
• to go from ethanenitrile to ethylamine?

  CH3CN + 4 [H] ----> CH3CH2NH2
• creating basic buffers using amines?

  • amines are a weak base, to make a basic buffer, a weak base and a salt of that weak base
  • for eg. for butylamine, it can be reacted with with a strong acid, like HCl, for form it's salt, butylammonium chloride
  • the acid added must be strong but not concentrated
• nitration conditions?

  • conc HNO3
  • conc H2SO4
  • 40  °C