ph-cl to ph-oH......use 1.koh,400*c,100 atm , cu catalyst....the mech is snae(substitution nucleophilic addition elimination)..

step 1)oH-&-H2O

step 2) therfore reso stabilisation.......cl- leaves(better leaving gp)

step 3)this gives benzyne formation

step 4)add oH-

step 5)then H2O,KOH,H+ leads to chelation due to moderate size of k+,  leads to the product

the high temp is b,coz phenol has partial double bond character(due to resonance)

the high pressure is implication of le-chatilier principle

info;

ahother industrial method is the raschig process

ph-cl to ph-OH

1.H2O,450*C,200atm,SiO2 catalyst

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