Organic ChemistryMain MenuLecture 1: Introduction to Molecular OrbitalsLecture 10: Intermolecular Forces and Intro to ReactivityLecture 11: Alkenes as Nucleophiles ILectures 12 and 13: Alkenes II & IIILecture 14: Benzenes as Nucleophiles ILecture 15 objectives and skillsLecture 2: Molecular Orbitals in Organic StructuresLecture 3: Molecular Orbitals and ResonanceLecture 4: Molecular Orbitals and AromaticityLecture 5: Nomenclature and IR SpectroscopyLecture 6: Stereochemistry ILecture 7: Stereochemistry IILecture 8: Newman and Fisher ProjectionsLecture 9: Conformations and Cyclohexane RingsJulio Terra2fb22914f73f9e5a767bf7fb83987dca0e153e4a
ee 40 = 0.4 S enantiomer and 0.6 racemic (0.3 S and 0.3 R) Total S = 0.4 + 0.3 = 0.7 = 70% Total R = 0.3 = 30%
ee 68 = 0.68 S enantiomer and 0.32 racemic (0.16 S and 0.16 R) Total S = 0.68 + 0.16 = 0.84 = 84% Total R = 0.16 = 16%
ee 84 = 0.84 S enantiomer and 0.16 racemic (0.08 S and 0.08 R) Total S = 0.84 + 0.08 = 0.92 = 92% Total R = 0.08 = 8%
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1media/section 2 key image.png2020-02-17T14:32:16-08:00Lecture 7: Stereochemistry II7image_header2020-08-28T08:13:19-07:00Objectives and Skills
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
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 7.2: 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
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 7.4: 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 ;)
