Configuration (chemistry)

Configuration isomers: Schematic representation of mirror-image pairs of enantiomers in (from top to bottom) three different (equivalent) visualization forms.

Under configuration is meant the spatial arrangement of atoms of a molecule or its spatial construction, which rotations around single bonds are not considered (this would be conformers ).

Explanations for the definition

Two molecules with the same constitution have a different configuration if they cannot be brought to an exact spatial correspondence ( congruence of the molecules) by rotating around single bonds . If the spatial structure of a molecule A can be changed by rotating around single bonds so that its spatial structure corresponds to that of a molecule B , molecules A and B have the same configuration.

Configurational isomers

If two molecules have the same constitution , i.e. the same order in which the atoms are linked, but a different spatial structure, then we are dealing with configuration isomers . All stereoisomers , except for the conformers, are configurational isomers. Examples are cis - trans isomers and enantiomers . With rare exceptions, configuration isomers have different physiological effects, which is why it is important to know the configuration of drugs and other active ingredients.

The number of possible configurational isomers of a compound results from the formula 2 ⁿ , where n is the number of the center of chirality.

See also

• Isomers
• Diastereomer
• Anomers
• absolute configuration

Web links

• Constitutional isomerism ( Chempage )

Individual evidence

1. ↑ Hisamichi Murakami: From Racemates to Single Enantiomers - Chiral Synthetic Drugs over the last 20 Years , Topics in Current Chemistry 269 ( 2007 ) 273-299, doi : 10.1007 / 128_2006_072 .
2. ↑ Everhardus Ariëns : Stereochemistry, a basis for sophisticated nonsense in pharmacokinetics and clinical pharmacology , European Journal of Clinical Pharmacology 26 (1984) 663-668, doi: 10.1007 / BF00541922 .