Question

What is the difference between a constitutional isomer, structural isomer, stereo isomer and enantiomer? Which ones are synonyms?

Answer 1

Constitutional isomer: Compounds with same molecular formula but have different connectivity of atoms are called as constitutional isomers. Constitutional isomers are structural isomers. (Synonyms).

E.g n-butane and 2-methyl propane.

Stereoisomer: compounds having same molecular formulas and connectivity of atoms but different in spatial orientation are called as stereoisomer.

E.g. cis but-2-ene and trans but-2-ene.

Enantiomer: Stereoisomers which are non-superimposable mirror images of each other are called as enantiomers.

S-Lactic acid and R-Lactic acid.