2- AROMATICS (PHENOLS)

Question 1

how is phenol synthesized from benzene (cumene process)

Answer 1

Question 2

how is cumene made from benzene and propene and what can it be used for?

Answer 2

constituent of crude oil, coal tar, and aviation gasoline (world war 2)
this is a aromatic electrophilic substitution reaction

Question 3

when attacking cumene, why does the radical take the proton between the two methyl branches and not another one?

Answer 3

that is the only one that can have delocalisation, which makes it more stabilized
for other protons, there is no possible delocalisation because the sp2 orbital is perpendicular to the ring p orbitals

Question 4

what is the dow process for the synthesis of phenol

Answer 4

Question 5

when is nucleophilic aromatic substitution possible?

Answer 5

when there is an EWG on the ring (for example NO2)
the EWG can help to pull away the extra negative charge

Question 6

what is the mechanism of the Dow process? (starting from chlorobenzene)

Answer 6

Question 7

how are ethers made from phenol?

Answer 7

simple SN2 reaction

Question 8

what do the reactivities of phenols and other alcohols depend on towards alkylation?

Answer 8

at basic conditions, it depends on the strength of the base
PhOH dissociates more readily than ROH when exposed to a weak base (based on equilibrium values)

in the presence of a strong base, ROH dissociates more readily, because RO- is not delocalised, so it will more readily make an ether

Question 9

what is the formula to find the equilibrium constant?

Answer 9

this helps to figure out which direction the reaction will go in
the formula is:
10^(pKa of acid on right-pKa of acid on left)

Question 10

cumene into phenol mechanism

Answer 10

Question 11

second part of cumene process mechanism

Answer 11