Illustrated Glossary of Organic Chemistry

Stereoisomer (configurational isomer): One molecule in a set of isomers that differ by the position of atoms in space, but are not constitutional isomers. Stereoisomers are either enantiomers or diastereomers.

Stereoisomer examples. Verify with models.

(R)-2-butanol
 (S)-2-butanol
 (R)-2-butanol and (S)-2-butanol
Enantiomers



(1R,2R)-2-chlorobromocyclohexane
 (1S,2R)-2-chlorobromocyclohexane
 (1R,2R)-2-chlorobromocyclohexane and (1S,2R)-2-chlorobromocyclohexane
Diastereomers



Cis-1,2-dichlorocyclohexane
 Cis-1,2-dichlorocyclohexane
 Cis-1,2-dichlorocyclohexane
Identical - not stereoisomers