1. Chapter 14 Aldehydes, Ketones, and Chiral Molecules

2. Chiral Compounds Chiral compounds
have the same atoms or groups arranged differently in space
have one or more chiral carbon atoms bonded to four different groups
are mirror images like your hands. Try to superimpose your thumbs, palms, back of hands, and little fingers

3. Hands Are Like Chiral Objects

4. Mirror Images The mirror images of
bromochloroiodomethane can align the H and I atoms, which places the Cl and Br atoms on opposite sides
chiral compounds cannot be superimposed

5. Achiral Structures Are Superimposable
When the mirror image of an achiral structure is rotated,
the structure is aligned with its initial structure
its mirror image is superimposable

6. Some Everyday Chiral and Achiral Objects

7. Learning Check
Identify each as a chiral or achiral compound.
A. B. C.

8. Solution Identify each as a chiral or achiral compound. A. B. C.
Chiral Chiral Achiral

9. Fischer Projections A Fischer projection
is a 2-dimensional representation of a molecule
places the most oxidized group at the top
uses vertical lines for bonds that go back
uses horizontal lines for bonds that go forward
assigns the letter L to the structure with the
—OH on the left
assigns the letter D to the structure with the
—OH on the right

10. Drawing Fischer Projections

11. Examples of Chiral Molecules

12. Learning Check Indicate whether each of the following pairs of Fischer
projections can or cannot be superimposed.

13. Solution Indicate whether each of the following pairs of Fischer
projections can or cannot be superimposed:
Cannot be
superimposed
Can be