On the other hand,
electron releasing groups, such as alkyl groups, in general, do
not favour the formation of phenoxide ion resulting in decrease
in acid strength Cresols, for example, are less acidic than phenol The greater the pKa
value, the weaker the
acid Rationalised 2023-24
208
Chemistry
Pyridine
R/Ar
+R’
l
OH
COC
R/ArOCOR + HCl
’
The reaction with carboxylic acid and acid anhydride is carried
out in the presence of a small amount of concentrated sulphuric
acid