Alcohols, Phenols and Ethers: Preparation Method: Aldehydes and Ketones Using Grignard Regents (For CBSE, ICSE, IAS, NET, NRA 2022)

Doorsteptutor material for competitive exams is prepared by world's top subject experts: get questions, notes, tests, video lectures and more- for all subjects of your exam.

Preparation Method

Aldehydes and Ketones Using Grignard Regents

Grignard reagents react with methanol (or formaldehyde) to give a primary alcohol.

Aldehydes and Ketones Using Grignard Regents

All other aldehydes yield secondary alcohols on reaction with Grignard reagents.

Aldehydes and Ketones Using Grignard Regents

With ketones, Grignard reagents give tertiary alcohols.

Aldehydes and Ketones Using Grignard Regents

Fermentation

It involves breaking down large molecules into simpler ones using enzymes. Usually, yeast is added as a source of enzymes.

Reactions of Alcohols

Acidic and Basic Behaviour

Alcohol behave both as acids and bases. They are weakly acidic. A strong base such as a hydride ion in sodium hydride , can remove the proton from the alcohol molecule and an alkoxide ion results.

Acidic and Basic Behaviour

When water is used as a base, the acid dissociation constant and can be written as follows:

Acidic and Basic Behaviour

Remember that the lower the value, higher is the acidity of the compound.

Formation of Alkoxides

Alcohols react with sodium or potassium metals to give the respective alkoxides.

Conversion to Alkyl Halides

These are hydrogen halides (such as , or ) , phosphorus tribromide and thionyl chloride . The reaction involves the breaking of bond of alcohol molecule.

Conversion to Alkyl Halides
Conversion to Alkyl Halides

Developed by: