aromatic compounds

Question 1

how did kekule describe the structure of benzene

Answer 1

alternating single and double bonds
planar and cyclic

Question 2

what were the issues with kekules benzoic structure

Answer 2

enthalpy of hydrogenation was not as exothermic as suggested
all bonds were the same length
did not react as expected (same as other alkenes)

Question 3

what was the delocalised model

Answer 3

suggested that electrons in the ring were delocalised with no double bonds and model was planar

Question 4

what mechanism does benzene react by

Answer 4

electrophillic substitution e.g nitrification of benzene

Question 5

what are the two types of friedel crafts reaction

Answer 5

acylation and alkylation

Question 6

what reagents are needed for
alkylation

Answer 6

haloalkane
halogen carrier
anhydrous conditions

Question 7

what reagents are needed for acylation

Answer 7

acid chloride
halogen carrier

Question 8

what is the structure of a benzene ring

Answer 8

planar ring
overlapping p orbitals
c-c bonds have equal length

Question 9

what types of directing groups activate the phenol ring and what happens

Answer 9

2 and 4 reactivity increases e.g OH and NH3

Question 10

what type of directing groups deactive the phenol ring

Answer 10

3 - derease reactivty e.g NO2