Alicylics & Aromatics

 A) Alicylics

• Carbon chains can form 2 types of closed loops 
• Alicylics are loops that are usually made with single bonds
• If the parent chain is a loop standard naming rules apply with one addition:

==>"Cyclo" is added in front of the parent chain

• There are 3 different ways to draw compounds:
  
   Example: Cyclopentane

                1) Complete structural diagram

 

2) Condensed structural diagram 

 

3) Line diagram 

• Numbers can start anywhere and can go C.W or C.C.W on the loop
• The Side chain numbers must be the lowest possible
• Loops can also be side chains
• The side chain though, is given the "cyclo" prefix 
• IE: 2 Cyclobutyl Octane

B) Aromatics

• Benzene(C6H6) is a cyclic hydrocarbon with unique  bonds between the carbon atoms
• Structurally it can be drawn with alternating double bonds
• Analysis shows that all six carbon bonds are identical and really represents a 1.5 bond
• This is due to the e- resonance
• e- are free to move all around the ring.

Benzene

Benzene (Lines represent double bonds)