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Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
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This problem set includes questions covering material from chapters 7, 8 and 9 in your textbook.
1. Define and explain the word ‘meso’ as it applies to stereochemistry. Draw three examples of meso compounds.
A meso compound is one that contains chiral centres but is achiral because of an intermal plane of symmetry. Thus,
switching the R,S configuration does not produce a unique enantiomer but rather just another copy of the same
compound.
2. Draw the product of this reaction. How many enantiomers and diastereomers could we draw for the starting
compound. How many for the product? If the numbers are different, explain why they have changed.
Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
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3. Explain why, in the reaction below, a single enantiomer of starting material yields a racemic mixture of
products? This is an SN1 reaction. What products would be formed in the SN2 version of this reaction (with
NaOMe)? Explain your answer thoroughly.
Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
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4. A secondary alkyl halide treated with water, acid, and heat can undergo E1 and SN1 reactions. Draw ALL
potential products of both of these reactions. (Consider multiple products!)
5. A secondary alkyl halide treated with a strong nucleophile/base such as NaOH will undergo E2 and SN2
chemistry. Draw ALL potential products of both of these reactions.
Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
6. Draw the products of the following reactions:
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Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
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7. The first molecule below is a well-known aromatic compound called ‘furan’. The second is a common laboratory
solvent called ‘tetrahydrofuran (or THF)’. Suggest why the second might have been given the name
tetrahydrofuran?
Discuss the hybridization of the oxygen atoms in the two compounds below. How and why are they different?
Tetrahydrofuran has 4 more hydrogens than furan. Thus the name 
The oxygen of furan is sp2 hybridized. This is because one of its lone pairs exists in a p orbital and is involved in the
aromatic ring – leaving just three regions of electron density (at 120o angles).
The oxygen of tetrahydrofuran is a typical sp3 hybridized oxygen atom like we see in alcohols and ethers. It has two
bonds and two equivalent lone pairs making a total of 4 regions of electron density.
Chem 275 Practice Problem Set – Friday, October 15, 2010 – J. Magolan
8. Name the following molecules:
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