The main reason for the study of pyrrole came from the work on the structure of haem; the blood respiratory pigment, and the chlorophyll; the green photosynthetic pigment of plants

The main reason for the study of pyrrole came from the work on the structure of haem; the blood respiratory pigment, and the chlorophyll; the green photosynthetic pigment of plants.

• The main reason for the study of pyrrole came from the work on the structure of haem; the blood respiratory pigment, and the chlorophyll; the green photosynthetic pigment of plants.

• Thiophene and its derivatives occurs in petroleum.

• Furan occurs widely in secondary plant metabolites, especially in terpenoids.

• Unsubstituted pyrrole, furan, and thiophene are usually obtained from petroleum.

Pyrrole, furan and thiophene are colorless liquids of boiling points 126o, 32o, and 84o respectively.

• Pyrrole, furan and thiophene are colorless liquids of boiling points 126o, 32o, and 84o respectively.

• Pyrrole has a relatively high boiling point as compared to furan and thiophene, this is due to the presence of intermolecular hydrogen bonding in pyrrole.

2) They tend to react by electrophilic substitution due appearance of –ve charge on carbon atoms due to delocalization as shown in the following resonance structures

• 2) They tend to react by electrophilic substitution due appearance of –ve charge on carbon atoms due to delocalization as shown in the following resonance structures