aromatic chemistry year 2

Question 1

similarities and differences in Kekule vs delocalised model

Answer 1

Similarities: sideways overlap of p orbitals, pie ring above and below plane of molecule
differences: kekule has 3 alternating pie bonds each with 2 delocalised electrons, whereas delocalised model has a single pie ring system, each containing 6 delocalised electrons with the pie electron density spread out across the ring

Question 2

activating and deactivating groups

Answer 2

Halogens are -2,4 directing group but have deactivating effect. All of the other -2,4 directors have an activating effect

–2,4 directing groups: amides, alcohols, alkanes, amines, halogens
- 3,5 directing groups: carboxylic acid, aldehyde, NO2, CN-,