Module 6.2.2- Amino acids, amides and chirality

• α-amino acid


  An amino acid in which the amine group is on the carbon adjacent to the carboxylic acid groupRCH(NH2)COOH

  
• Amino acid + Acid (HCl)

  ammonium salt

  NH2 group on amino acid becomes NH3+ since it is basic (accepts proton from the acid)

  
• Amino acid + Aqueous Alkali (NaOH)


  salt + water

  carboxylic acid group is acidic hence why it becomes COO-

  
• Amino Acid + Excess Alcohol + H2SO4

  Ester + Water

  NH2 is protonated by acid

  
• Amides


  RCONH2

  
• How are amides formed?

  Acyl chloride + Ammonia

  Carboxylic acid + Amine group
• Secondary Amide


  RCONHR

  
• Naming a tertiary amide (hard)

  N,N-dimethylpropanamide

  
• Naming a tertiary amide 2 (hard)

  N-ethyl-N-methylpropanamide

  
• Name the 2 types of stereoisomerism

  E-Z isomerism

  Optical isomerism
• Optical isomerism


  non-superimposable mirror images about a chiral centre

  
• Enantiomers


  molecules that are mirror images of each other
• Chiral centre


  Four different groups attached to a carbon atom.

  
• Identifying chiral centres in molecules