Qu 1: |
Epoxides can be
formed in two ways, either epoxidation of an alkene or via the halohydrin. |
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(a) What is the
stereochemistry of epoxidation ? |
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(b) If Z-2-butene
is treated with peracetic acid, what is the stereochemistry of the epoxide
?
Assign the configurations to any chiral centers. |
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(c) If E-2-butene
is treated with peracetic acid, what is the stereochemistry of the epoxide
?
Assign the configurations to any chiral centers. |
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(d) What is the
stereochemistry of halohydration ? |
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(e) If Z-2-butene
is treated with HOCl then NaOH, what is the stereochemistry of the epoxide
? |
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Qu 2: |
What is the major
product from the reaction of ethylene oxide with each of the following
? |
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(a) H3O+ |
(b) aq. NaOH |
(c) NaOCH3 in
CH3OH |
(d) CH3OH
with cat. H2SO4 |
(e) LiAlH4
/ THF then acidic work-up |
(f) PhMgBr then
acidic work-up |
(g) NaSCH3
in ether, then acidic work-up |
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Qu 3: |
What is the major
product from the reaction of propylene oxide with each of the reagents
in Qu 2 ? |
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Qu 4: |
Draw a curly arrow
mechanism to rationalise the stereochemistry of the following reactions: |
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