Book Cover Organic Chemistry 4e Carey
Online Learning Center

Chapter 24: Phenols

Summary | Phenols | Preparation of Phenols | Reactions of Phenols | Reactions of Aryl Ethers | Spectroscopic Analysis | Self Assessment | Quiz |

Reactions of Phenol

Chapter 24: Phenols

Electrophilic Aromatic Substitution

electrophilic aromatic substitution of phenols

Reaction type: Electrophilic Aromatic Substitution


Nitration dil. HNO3 in H2O or CH3CO2H
HNO3 / H2SO4
conc. H2SO4
H2SO4 or SO3 / H2SO4
X2 / Fe or FeX3
ROH / H+ or RCl / AlCl3
RCl / AlCl3
RCOCl / AlCl3
RCOCl / AlCl3
aq. NaNO2 / H+
Related reactions

Acylation of Phenols

C vs O acylation of phenols
Reaction type: C-acylation = electrophilic aromatic substitution
O-acylation = nucleophilic acyl substitution
The Fries rearrangement of aryl esters is promoted by AlCl3

Related reactions

Carboxylation of Phenols (Kolbe-Schmitt reaction)

reaction of a phenolate with CO2
Reaction type: Electrophilic Aromatic Substitution


hydrogen bonding in salicylate
Check out the CHIME image for the intramolecular hydrogen bond by looking the the position of the shared H atom with respect to the two oxygen atoms

Aspirin is the acetyl ester of salicylic acid (hence ASA),  how would you make aspirin from salicylic acid ? click for diagram
Can you think of other reactions of nucleophilic species with carbon dioxide ? Grignard reagents, RMgX, react with CO2 to give carboxylic acids, RCO2H (click to review)

Study Tip:
Consider the phenolate to be an enolate, hence reactions at the a-C are typically favored.

Step 1:
The nucleophilic phenolate (reacting like an enolate) reacts with the electrophilic carbon of carbon dioxide in the ortho position (compare this with an Aldol reaction)
mechanism of the carboxylation of a phenolate
Step 2:
The non-aromatic cyclohexadienonecarboxylate intermediate tautomerises to the more stable aromatic enol which is further stabilized by an intramolecular hydrogen bond.  An acidic work-up will generate the carboxylic acid.


Preparation of Aryl Ethers


preparation of aryl ethers

Reaction type : Nucleophilic Substitution


Question :
Is this method suitable for the preparation of diaryl ethers such as Ph-O-Ph ? No, since aryl halides don't undergo simple nucleophilic substitution reactions

Related Reactions

Oxidation of Phenols


oxidation of a 1,2-hydroxybenzene      oxidation of a 1,4-dihydroxybenzene
Loss of a proton and an electron generates a phenoxy radical
Loss of a second proton and a second electron completes the oxidation.

Can you draw a curly arrow scheme that shows how the quinone may be formed from a diradical  ? click for a diagram

Related Reactions


Begin a search: Catalog | Site | Campus Rep

MHHE Home | About MHHE | Help Desk | Legal Policies and Info | Order Info | What's New | Get Involved

Copyright ©2000 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use and Privacy Policy.
McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies.
For further information about this site contact

Corporate Link