Lecture 7: Stereochemistry II
KEY INFORMATION SUMMARY
PROBLEMS
Problem 7.1: Optical Rotation and Polarimetry
- Which of the following compounds are optically active? SOLUTION
- Describe how polarimetry can distinguish between enantiomers. SOLUTION
Problem 7.2: Mixtures of Enantiomers
- A student is developing a new method form synthesizing ibuprofen. The following ee values were obtained from three trials: 40, 68, 84 (in favour of the active, “S” enantiomer). Determine the molar ratios of S:R for each trial. SOLUTION
- A second student was working on an alternative method and achieved an ee value of zero. Which student is having the better success at synthesizing more of the active “S” enantiomer? SOLUTION
If you made some mistakes or want to practice more, review the concepts that gave you trouble and work on this extra problem. If you're good, move to the problem below ;)
Problem 7.3: Multiple Chiral Centers
- Determine the total number of stereoisomers for each structure below. SOLUTION
- Select one stereoisomer (of those possible), for each structure, and change the configuration around one stereocenter, what would be the relationship between the two stereoisomers? SOLUTION
Problem 7.4: Meso and Diastereomers
Draw the remaining possible stereoisomers for each compound below, identify the chiral centers, classify the following compounds as chiral or meso and identify the relationship between each possible pair for each compound. SOLUTION
If you made some mistakes or want to practice more, review the concepts that gave you trouble and work on this extra problem. If you're good, move to the next lecture ;)