Question

4. Draw an organic compound for each set of criteria, or explain why the criteria render a structure impossible: a) What is a single structure that has a constitutional isomer, a geometric isomer, and an enantiomer? Please draw the original structure, along with its constitutional isomer, its geometric isomer, and its enantiomer - or explain why a single compound cannot have a constitutional isomer, a geometric isomer, and an enantiomer. b) What is a single structure which is chiral and is also meso? Please draw the original structure as well as its meso counterpart - or explain why a single structure cannot be chiral and meso at the same time. c) What is a single structure that has a constitutional isomer, a geometric isomer, but no enantiomer? Please draw the original structure, along with its constitutional isomer and its geometric isomer - or explain why a single compound cannot have a constitutional isomer and a geometric isomer without having an enantiomer. d) What is a single structure which is chiral and has no constitutional isomer? Please draw the original structure only - or explain why a single structure cannot be chiral without having a constitutional isomer.

Answer 1

Constitutional isomers

Compoundshaving the same molecular formula but different connectivity between atoms.

Geometrical isomers

Compoundshaving the same molecular formula , same connectivity between atoms but different geometric structure.

Enantiomers

Compounds having the same molecular formula but differ in the optical activity. Form non-superimposable mirror images.

Part b

Answer

Has chiral carbon , but due to internal plane of symmetry, is optically inactive

Part c

Answer

Constitutional isomers

Due to the absence of chiral carbon. There are no enantiomers