STEREOCHEMISTRY: CHIRAL MOLECULES
5.1 ISOMERISM: CONSTITUTIONAL ISOMERS AND
STEREOISOMERS
- Isomers are different compounds that have the same molecular formula.
- Constitutional isomers are isomers that differ because their atoms are connected
in a different order.
Molecular Formula Constitutional isomers
C 4 H 10 CH^3 CH^2 CH^2 CH^3 and H 3 C CHCH 3
CH 3
Butane IsobutaneC 3 H 7 Cl CH^3 CH^2 CH^2 Cl and H 3 C CHCl
CH 3
1-Chloropropane 2-Chloropropane
C 2 H 6 O CHEthanol^3 CH^2 OH and Dimethyl etherCH^3 OCH^3- Stereoisomers differ only in arrangement of their atoms in space.
Cl
ClCC HH HCCl CClHcis-1,2-Dichloroethene (C 2 H 2 Cl 2 ) trans-1,2-Dichloroethene (C 2 H 2 Cl 2 )
- Ennatiomers are stereoisomers whose molecules are nonsuperposable mirror
images of each other.
MeMeHHMeMeHH