Name 3 things phenols are used as
Any 3 of Plastics Antiseptics Disinfectants Resin in paint
how do phenol and benzene differ?
phenol is a benzene ring with a -OH gp attached directly to it
while benzene is just benzene
is phenol a weak or strong acid, why?
weak acid ( so it donates e-) this is due to the high stability so it cant fully dissociate
why is there a negative charge on the phenol after dissociation
as the O’s negative charge is spread along the whole delocalised system
why is phenol more reactive than benzene (4)
- lone pait of e- from oxygen (p orbital) overlaps with delocalised pi system
- delocalised pi system in phenol has a higher electron density
- so electrophiles (proton acceptors) are more attracted to the benzene ring in phenol
- so electrophilic substitution is more likely to happen
what one thing can phenol not react with and why
carbonate, its such a weak acid
how can u test for a benzene
electrophilic substitution of benze
(just like alkenes)
decolourises if benzene BUT also white ppt formed
name the 2 directing groups
- 2-,4- directing group
2. 3- or 5- directing group
what do directing gps do
they are already attached to the benzene ring and this will change the benzenes e- density so it will guif other molecules to attach to nxt
we have a -OH or -NH2 attached to a benzene ring
- where will the next molecules attach to?
- what happens to reactivity and why?
- does it take or give e- to the benzene
2,4 position from OH or NH2
increases reactivity as it gives e- to ring as its a negative molecule so electrophiles are attracted to it more
donates e-
we have a -NO2 attached to a benzene ring
- where will the next molecules attach to?
- what happens to reactivity and why?
- does it take or give e- to the benzene
3 position from NO2
reactivity deacreases as NO2 is a positive molecule so it take electrons away so there is a lower e- density in the benzene ring. so new molecules attach at 3
takes electrons
