3.12 Disubstituted Cycloalkanes: Stereoisomers

	Stereoisomers are isomers that have same constitution but different arrangement of atoms in space

Slide 2

1,2-Dimethylcyclopropane

	There are two stereoisomers of 1,2-dimethylcyclopropane.
	They differ in spatial arrangement of atoms.

1,2-Dimethylcyclopropane

	cis-1,2-Dimethylcyclopropane has methyl groups on same side of ring.
	trans-1,2-Dimethylcyclopropane has methyl groups on opposite sides.

Slide 5

Slide 6

Slide 7

"Trans stereoisomer is more stable..."

	Trans stereoisomer is more stable than cis, but methyl groups are too far apart to crowd each other.

Slide 9

Slide 10

"Analogous to 1,4 in..."

	Analogous to 1,4 in that trans is more stable than cis.

Slide 12

Slide 13

"Unlike 1,2 and 1..."

	Unlike 1,2 and 1,4;  cis-1,3 is more stable than trans.

Slide 15

Slide 16

"Compound Orientation -DH�"

	Compound Orientation -DH�
	cis-1,2-dimethyl ax-eq 5223 trans-1,2-dimethyl eq-eq 5217*
	cis-1,3-dimethyl eq-eq 5212* trans-1,3-dimethyl ax-eq 5219
	cis-1,4-dimethyl ax-eq 5219 trans-1,4-dimethyl eq-eq 5212*