Discussion Essay

Instructions:
Read the instructions carefully and answer the following questions in the space provided. Then
attach the PDF file on Discussion Board for peer discussion and peer review.
1. In a few sentences define each of the three main classes of isomers below. Configurational
Isomers can be further classified as either enantiomers or diastereomers and should also be
discussed. Your descriptions should enable your peers to quickly and easily compare and
contrast the differences between the different classes of isomers.
A. Constitutional Isomers (or Structural Isomers)
B. Conformational Isomers
C. Configurational Isomers (or Stereoisomers)
I. Enantiomers
II. Diastereomers
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2. Analyze each pair of compounds below. Identify which class of isomers each pair of
structures represent. Your choices are: (i) constitutional, (ii) conformational, (iii)
enantiomers, or (iv) diastereomers or (v) identical (non-isomers). Only one label for each
pair should be used. For each case show work (drawings, (R)/(S), rotation of bonds, chairflips, etc) which led you to each answer for the pairs below. [During your peer review, any
differences of answers between you and your peers can be discussed and corrected as
needed.]
Note: Various projections may be used when drawing chemical structures including bondline structures (using proper dash/wedge bonds), Newman projections, chair structures (for
cyclohexane derivatives), Haworth projections, and Fischer projections. These projections
just represent different vantage points of visualizing a chemical structure and can be
interconverted from one projection to another. Each different projection has been labeled
for you below. These are all utilized throughout the text book.
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3. Analyze the structures for Compound A and Compound B shown below. Answer and
discuss each question (a) and (b), respectively.
a. What type of isomers do these represent?
b. Which compound is more stable? (Hint: You will need to draw the chair structures
for each compound (4 total chairs, two for each compound) and
compare/contrast/analyze the various 1,3-diaxial interactions in order to justify this
answer. Show your work clearly