Methods of Preparation of Alcohols

IMPORTANT

Methods of 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 Methods of 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,

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The compound D is –

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?

HARD
IMPORTANT

R-MgX+HCHO  [P], here P is

MEDIUM
IMPORTANT

In the conversion of starch into alcohol, the following enzymes are used:

HARD
IMPORTANT

Propene on oxidation with diborane in presence of alkaline hydrogen peroxide gives _______.

EASY
IMPORTANT

The major products P, Q and R in the following reaction sequence, are

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EASY
IMPORTANT

Ph-CH2-CH=CH2dil H2SO4X, Identify product 'X' is :

HARD
IMPORTANT

Five isomeric p-substituted aromatic compound (A) to (E) with molecular formula C8H8O2 are given for identification. Based on the following observation, give the structures of the compounds.

i. Both (A) and (B) form a silver mirror with Tollen's reagent. (B) also gives a positive test with neutral FeCl3 solution.

ii. (C) gives positive iodoform test.

iii. (D) is readily extracted in aqueous NaHCO3 solution.

iv. (E) on acid hydrolysis gives 1, 4-dihydroxybenzene.

Compound (E) is :

MEDIUM
IMPORTANT

Which of the following are used to convert RCHO into RCH2OH?

HARD
IMPORTANT

The reduction of acetone by Mg-Hg gives:

MEDIUM
IMPORTANT

Through which of the following reactions number of carbon atoms can be increased in the chain?

HARD
IMPORTANT

Using Grignard reagent, suggest synthesis of following alcohol from aldehydes or ketones. Whenever possible, suggest more than one combination.

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HARD
IMPORTANT

Using Grignard reagent, suggest synthesis of following alcohol from aldehydes or ketones. Whenever possible, suggest more than one combination.

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HARD
IMPORTANT

Using Grignard reagent, suggest synthesis of following alcohol from aldehydes or ketones. Whenever possible, suggest more than one combination.

CH3-CH2-CH2-OH

HARD
IMPORTANT

Using Grignard reagent, suggest synthesis of following alcohol from aldehyde or ketone. Whenever possible, suggest more than one combination.

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HARD
IMPORTANT

Write the structure of carbonyl compound that can be converted by reduction methods into following alcohol.

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HARD
IMPORTANT

Write the structure of carbonyl compound that can be converted by reduction method into following alcohol.

CH32CH-CH2-OH