A compound containing one of the following structural units on heating with I2 and NaOH will give a yellow precipitate of Iodoform ( CHI3). This is called Iodoform test.
The reaction is used as a diagnostic test for the presence of the groups.
Apart from using as a diagnostic test it can also be used to prepare certain carboxylic acids with considerable ease.
- Give the structure of compounds which give a positive Iodoform test and have the following characterisitics.
- An aldehyde.
- Two ketones.
- An aromatic ketone.
- An alcohol with four carbon atoms.
- Give the structure of compounds which do not give a positive Iodoform test and have the following characteristics.
a) An aldehyde.
b) An aromatic ketone.
c) A cyclic ketone.
7). Give reasons:
a) 3-Pentanone has a methyl and a carbonyl group, still does not give a positive Iodoform test.
c) 1-Propanol does not give a positive Iodoform test.
d) Formation of Iodoform can be used as a test to detect a methyl ketone while formation of chloroform cannot be used.
e) Write the equations for the preparation of the following carboxylic acids through haloform reaction.
For answers write to: firstname.lastname@example.org