Drill: Name the Following
C C C
C-C-C-C-C-C-C
C-C
Stereo-chemistry
StereochemistryAny chemistry which involves
orientation in space
Use Models
SymmetryReferring to anything
that can be divided on some plane into
identical parts
SymmetryIn molecules, planes of symmetry can be determined along
any bond axis
Symmetric Compounds
Compounds with at least one plane of
symmetry
Symmetric Compounds
The mirror images of symmetric compounds
are identical
Asymmetric Compounds
Compounds with no plane of symmetry
Asymmetric Compounds
•The mirror images of asymmetric compounds are not identical. They are optical isomers.
Optical Isomers
•Mirror images of asymmetric compounds are optical isomers or stereoisomers
Stereoisomerism of C
•A carbon center must be bound to 4 different
things to be asymmetric
Stereoisomerism of C
•Any carbon center bound to 3 or less
things has at least one plane of symmetry
C C C
C-C-C-C-C-C-C
C-C
Find an assymetric carbon center:
C C C
C-C-C-C-C-C-C
C-C
Stereoisomerism of C
•Use modeling
Stereoisomerism of Carbon Chains
•The constituents on two adjacent carbons spend
more time in the staggered position
Stereoisomerism of Carbon Chains
•Use modeling to show aligned & staggered
positions
Polarity of Hydrocarbons•Hydrocarbons are non-polar
Perfectly Symmetrical Compounds
All perfectly symmetrical compounds are
non-polar
Less than perfectly Symmetrical Compounds•Compounds with any
plane of asymmetry can be polar if the
bonds are polar
Diffusion
•Movement down an energy gradient
Thermochemistry•Compounds will
eventually move to the lowest possible energy state (the most stable
state)
Thermochemistry of Organic Compounds•Stability is sometimes determined by how the
compound interferes with its surroundings
Thermochemistry of Organic Compounds
•To increase stability, organic compounds
tend to curl up
Thermochemistry of Organic Compounds
•Ring structures are more stable than their
corresponding straight chain structures
Drill: Name:
Name & draw an optical isomer of:
H3C-CH2
H3C-C-CH2-CH2-CH3
H
Draw & Name at least 5 isomers of
C6H14
