For the molecules shown,
(i) count the number of stereocenters present and
(ii) draw all possible stereoisomers.
(iii) Identify the relationships between stereoisomers as enantiomers or diastereomers.
(a)

Identify

1. constitutional isomers

2. stereoisomers

3. cis–trans isomers

4. chiral compounds

Draw the mirror image of the following molecule. Then, using the mirror image generated, switch the spatial orientation at the asymmetric center. Is the final structure the enantiomer of the original? If not, what is it?

For each pair, give the relationship between the two compounds. Making models will be helpful.

(h)

Make a model and draw a three-dimensional structure for each compound. Then draw the mirror image of your original structure and determine whether the mirror image is the same compound. Label each structure as being chiral or achiral, and label pairs of enantiomers.

(e)

(f)

(i) Which of the following pairs of compounds would you expect to have different physical properties?

(ii) What is the relationship between each of the pairs?

(iii) Assign the absolute configuration of each stereocenter to confirm your answer.

(a)

Draw the structure for a compound with molecular formula C₂H₂I₂F₂

a. that is optically inactive because it does not have an asymmetric center.

b. that is optically inactive because it is a meso compound.

What is the relationship between these two sugars if they have the same molecular formula but differ in the arrangement of atoms in space?

Which of the following best describes the relationship between structural isomers?