An introduction to A level organic chemistry Flashcards
Explain what is meant by delocalized electrons in benzene.
Electrons that are free to move around the molecule in the pi bonding system above and below the plane of carbon atoms in benzene ring.
Define racemic mixture.
A mixture containing equal amount of a pair of enantiomers.
Explain the meaning of optically active.
A substance that is able to rotate the plane of polarised light.
Give two reasons why it might be desirable to synthesise a single optical isomer for use as a drug.
- Other isomer can have side effects.
- Avoid the need to separate the optical isomer to form the pure active isomer.
How to produce a single / pure enantiomer?
Chiral catalyst.
How to separate two enantiomers?
Optical resolution using chiral auxiliary.
Define chiral auxiliary.
A special molecule that only interact with one type of isomer in a mix.
Define enantiomers.
Molecules that rotate the plane of polarised light in opposite directions.
Suggest one disadvantage of producing two enantiomers in a synthesis.
Lower yield of biologically active molecule.
