Classification Alcohols, Phenols, and Ethers Formula

Explore key formulas for alcohols, phenols, and ethers in organic chemistry, understanding their structures and properties for academic excellence. Alcohols Organic compounds containing hydroxyl (-OH) group as a functional group bonded to a saturated carbon atom.

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Alcohols: Organic compounds containing hydroxyl (-OH) group as a functional group bonded to a saturated carbon atom.

Example: CH3OH (Methanol)

Phenols: Compounds in which the hydroxyl group is directly attached to an aromatic ring.

Example:  C6H5OH (Phenol)

Ethers: Compounds that contain an oxygen atom bonded to two alkyl or aryl groups.

Example: CH3OCH3 ​ (Dimethyl ether)

Classification of Alcohols

Primary (1°): The carbon atom bonded to the -OH group is bonded to only one other carbon atom.

Example: Ethanol CH3CH2OH

Secondary (2°): The carbon atom bonded to the -OH group is bonded to two other carbon atoms.

Example: Isopropanol CH3CHOHCH3

Tertiary (3°): The carbon atom bonded to the -OH group is bonded to three other carbon atoms.

Example: Tert-butanol (CH3)3COH 

Phenols: Typically not classified in the same way as alcohols since the -OH is always attached to an aromatic ring.

Ethers: Symmetrical (Simple) Ethers: Same alkyl groups on both sides of the oxygen.

Example: Dimethyl ether CH3OCH3 ​ 

Unsymmetrical (Mixed) Ethers: Different alkyl or aryl groups on either side of the oxygen.

Example: Ethyl methyl ether CH3OCH2CH3 ​ 


Alcohols: Named with the suffix “-ol” added to the name of the parent alkane.

Example: CH3CH2OH is Ethanol.

Phenols: The word “phenol” itself is used if there are no substituents. If substituents are present, their positions are indicated using numbers.

Example: C6H4(OH)(CH3) can be named as m-cresol where the methyl group is meta to the hydroxyl group.

Ethers: In the common naming system, name the two alkyl or aryl groups alphabetically and add “ether”.

Example: CH3OCH2CH3 ​ is ethyl methyl ether. In the IUPAC system, it’s named as alkoxyalkanes. For example, the above can be named as methoxyethane.

Preparation of Alcohols

From Alkenes: 

Acid-catalyzed hydration.

CH2=CH2 ​ + H2O → CH3CH2OH (in the presence of acid)

From Grignard Reagents:

CH3MgBr + H2O→ CH4 ​ + Mg(OH)Br 

Reduction of Carbonyl Compounds: Using reducing agents like LiAlH4 or NaBH4.

RCHO + 2[H] → RCH2OH

Also Check – Acids and Bases Formula: Types of Reaction

Preparation of Phenols 

From Halobenzenes: Using aqueous NaOH at high temperatures (called the Dow process).

C6H5Cl + NaOH → C6H5OH + NaCl 

From Benzene Sulphonic Acid: Through fusion with NaOH.

C6H5SO3H + 3NaOH → C6H5OH + 3NaHSO3

Also Check – PH of Weak Acid Formula

Physical and Chemical Properties of Alcohols and Phenols 

Boiling Point: 

Alcohols and phenols have higher boiling points than their corresponding hydrocarbons due to hydrogen bonding.


Phenols are more acidic than alcohols due to the delocalization of the negative charge over the aromatic ring in the phenoxide ion.

Reaction with Halides: 

Alcohols react with halide ions in the presence of acids to form haloalkanes.

ROH + HX → RX + H2

This is termed as the Lucas Test when using anhydrous ZnCl2 with alcohols to distinguish between primary, secondary, and tertiary alcohols.

Ester Formation: 

Alcohols react with carboxylic acids to form esters in the presence of an acid catalyst.



While secondary alcohols can be oxidized to ketones, primary alcohols can be converted to aldehydes and then to carboxylic acids. Alcohols in the tertiary stage do not simply oxidize.

Reimer-Tiemann Reaction:

 Phenol, when treated with chloroform in the presence of aqueous NaOH, results in the formation of salicylaldehyde. This reaction involves the formation of dichlorocarbene.

C6H5OH + CHCl3 ​ + 4NaOH → C6H4CHO(OH) + 3NaCl + 3H2

Williamson Ether Synthesis: 

An alcohol is first converted into a sodium alkoxide, which then reacts with an alkyl halide to form an ether.

RONa + R ′ X → ROR ′ +NaX 

Alcohols, Phenols, and Ethers Formula FAQs

Q1. Which is more acidic: alcohol or phenol?

Ans. Phenol. 

Q2. How is ethyl ether prepared from alcohols?

Ans. By dehydration of alcohols using concentrated sulfuric acid (Williamson ether synthesis). 

Q3. What is the common name for dimethyl ether?

Ans. Wood spirit. 

Q4. Which reacts more readily with sodium: alcohol or phenol?

Ans. Phenol. 

Q5. What is the main product when phenol reacts with zinc dust?

Ans. Benzene. 

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