Alicyclics and Aromatics!

In today's class we learned how Carbon chains can form two different types of closed loops.

The above diagram is known as cyclopentane

-Alicyclics are loops that are usually made with single bonds.

When naming if the parent chain is a loop the standard naming rules apply, there is only one change and this is that one must add "cyclo-" in front of the parent chain

We also learned about a new, simpler way of drawing these organic compounds:

When numbering off an organic compound to find the lowest number for the side chains you can start anywhere in the circular shape. One can go clockwise or counter clockwise, which ever way that will give you the side chain numbers to be the lowest.

-Loops can be found in not only the parent chain, but also in the side chain, in this case the same naming rules apply but the side chain is given a "cyclo-" in front of it.

Aromatics

Benzene (C6H6) is a cyclic hydrocarbon with unique bonds between the carbon atoms.

Careful analysis allows us to see that all 6c-c bonds are identical and really represent a 1.5 bond

This is due to electron resonance and so the electrons are free to move around Benzene's interior ring.

Aromatic Nomenclature

A benzene molecule is given a special diagram to show its unique bond structure.

Benzene can be found as a parent or a side chain

When a side chain it is given the name "Phenyl."