Experiment 92

Objective

To prepare salicylaldehyde from phenol using the Reimer-Tiemann reaction, with chloroform and sodium hydroxide.

Introduction

The Reimer-Tiemann reaction involves the formation of salicylaldehyde from phenol by heating it with chloroform (CHCl₃) and sodium hydroxide (NaOH) at 60-70°C. This reaction introduces a formyl group (-CHO) onto the aromatic ring of phenol.

Reaction Overview Phenol reacts with chloroform in a basic medium to produce salicylaldehyde.

Materials

Chemicals

·       Phenol

·       Chloroform (CHCl₃)

·       Sodium hydroxide (NaOH)

Apparatus

·       Test tube

·       Test tube holder

·       Thermometer

·       Bunsen burner

Reagents

·       Use 10 mL of phenol, 10 mL of chloroform, and 3.659 g of sodium hydroxide.

Procedure

1.    Preparation of Reaction Mixture

o   Place phenol, chloroform, and sodium hydroxide together in a test tube.

2.    Heating

o   Heat the mixture at 60-70°C, maintaining a constant temperature.

3.    Observation of Product Formation

o   After a few minutes, salicylaldehyde forms as the reaction proceeds.

Observation

Salicylaldehyde, a colorless compound, is produced as the reaction product.

Questions

1.    How is salicylaldehyde produced in this reaction?

2.    Why is chloroform used in the production of salicylaldehyde?

3.    What are the uses of salicylaldehyde?