Heterocyclic Chemistry Flashcards
What are heterocyclic compounds?
Ring compounds containing at least one heteroatom which are Oxygen, Nitrogen or Sulfur.
What is the structure of Pyridine?
It is a benzene (aromatic) with one carbon atom replaced with nitrogen.
It is planar with 5 sp2 carbon and 1 sp2 hybridised nitrogen atom.
It has a cycle of 6 pi electrons.
How does the reaction with Pyridine work?
The lone pair on the nitrogen accepts a proton to form a pyridinium ion.
What is the correct reaction that will work with Pyridine?
Electrophilic substitution.
When does substitution occur in Pyridine?
Occurs mainly at C-2 to C-4
The positive charge at C-2 is more delocalised than C-3.
Where does Pyrrole come from?
1,4 dicarbonyl compounds.
A nitrogen atom derived from ammonia or a 1 degree amine.
Where does Furan come from?
1,4 - dicarbonyl compounds.
The oxygen atom is derived from one of the carbonyls.
Catalyzed by mineral or Lewis acid.
