Preparation of Alcohols

IMPORTANT

Preparation of Alcohols: Overview

This Topic covers sub-topics such as Methods of Preparation of Alcohols, Mechanism of Acid Catalysed Hydration of Alkenes, Preparation of Alcohols by Reduction of Aldehydes and Ketones and, Preparation of Alcohols By Acid Catalysed Hydration of Alkenes

Important Questions on Preparation of Alcohols

HARD
IMPORTANT

Match the conversions with the reagents that are used in the process:

i. Phenol to benzoquinone a. H2O/H+
ii. Propanone to 2-methylpropan-2-ol b. Na2Cr2O7/H2SO4
iii. Propene to propan-2-ol c. CH3MgBr/H2O

HARD
IMPORTANT

An organic compound A   ( C 3 H 6 O)  on reduction forms compound B   ( C 3 H 8 O) . B reacts with HBr to form the compound C. C with Mg forms Grignard reagent D which reacts with A to form a product which on hydrolysis gives E. Identify A to E.

HARD
IMPORTANT

In the following sequence of reactions,

Question Image
The compound D is –

HARD
IMPORTANT

Between 2-methyl-butan-2-ol and 2-methyl-butan-1-ol, which cannot be produced by the reduction of either an alcohol or an aldehyde? Why?

MEDIUM
IMPORTANT

What happens when Pent-1-ene is reacts with dilute sulphuric acid.

HARD
IMPORTANT

Reaction of Question Image with two equivalent of CH3MgBr followed by acidic hydrolysis forms compoundP, Dehydration of P forms compoundQ. Answer the following question on the basis of above write up.

What type of alcoholic (OH) group is present in compound (P)?

HARD
IMPORTANT

Reaction of Question Image​​​​​​​ with two equivalent of CH3MgBr followed by acidic hydrolysis forms compoundP, Dehydration of P forms compoundQ. Answer the following question on the basis of above write up.

Which simplest product is formed by reductive ozonolysis of compound Q?

HARD
IMPORTANT

How can one degree alcohol be converted to two degree alcohol without changing the number of carbon?

HARD
IMPORTANT

What is the product formed in the following reaction?

CH3-CH=CH2 (ii) H2O2, OH-(i) BH3, THFProduct

HARD
IMPORTANT

An organic compound A,C6H10O on reaction with CH3MgBr followed by acid treatment gives compound B.The compound, B on reaction with HBr gives compound, C. Identify compound A,B and C.

EASY
IMPORTANT

Identify the catalyst in the hydration of alkenes to produce alcohols.

EASY
IMPORTANT

The product 'A' of the following reaction is

COg+2H2gCuZnO-Cr2O3A

MEDIUM
IMPORTANT

The major product formed in the following reaction is

Question Image 

 iiNaOH,H2O2 iBH32

EASY
IMPORTANT

In which of the following the adduct obtained gives n-Propyl alcohol on hydrolysis?

MEDIUM
IMPORTANT

In which of the following reactions 2-Phenylbutan-2-ol cannot be prepared?

EASY
IMPORTANT

Explain the mechanism of acid catalysed hydration of alkenes to form alcohols.

EASY
IMPORTANT

When 1:2 equivalence ratio of the gases X and Y are heated to 573K-673 K at 200 -300 atm in the presence of ZnO-Cr2O3 catalyst, methanol is formed. Here, the gases Xand Y are _____ and _____ respectively.

HARD
IMPORTANT

Which of the following compound gives 3-Ethylpentan-3-ol by the action of ethyl magnesium iodide followed by acid hydrolysis?

HARD
IMPORTANT

Which of the following alcohols cannot be prepared by reduction of carbonyl compounds?

MEDIUM
IMPORTANT

Which one of these reactions will produce a primary alcohol?