Name:
Chem 22
Exam 2
04/05/00
1.
Give the product (s) of each of the following reactions. For the reactions that have multiple steps
give the product(s) for each step.
a)
b)
C)
d)
e)
f)
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2.
Give the reagent (s) for each of the following reactions
a)
b)
c)
d)
3)
Using the given starting material, any necessary inorganic reagents, and any carbon containing
compounds with no more than two carbon atoms, indicate how the following synthesis could be
carried out.
a)
2
b)
4.
Propose a mechanism for the following reaction. Show arrows for each step and include
important resonance structure.
a)
3
b) give a detailed, stepwise mechanism for the esterification of benzoic acid with methanol in the
presense of an acid catalyst.
c)
The above esterification reaction is an equilibrium reaction. Which of the following
conditions will drive the equilibrium towards ester fomation
1)
2)
3)
4)
5.
addition of water
removal of water
addition of an inorganic acid as a catalyst
addition of alcohol
Draw the structures or give the names of each of the following compounds
a)
b)
4
c)
d)
6.
Do you expect the following reaction to go in the direction shown? Why or why not?
5
7.
i) When 4-chlorobutanoyl chloride is treated with methanol it gave a compound with a molecular
formula C5H9O2Cl. The 1H NMR spectrum of this product is given below
Analyze the spectra in terms of
a. integration
b. splitting pattern (coupling pattern)
c. chemical shift
and then draw the structure and indicate which peak belong to which protons
ii) How many peaks would the 13C spectra of the above compound have?
a)
b)
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8.
Match the following C = O stretching frequencies 1735, 1800, 1760, 1650 cm-1. with the
appropiate structures listed below and explain your answer.
.
Multiple Choice (Choose only one answer)
1. What product is formed from the following reaction sequence: butyl bromide + sodium cyanide,
followed by addition of HCl, water, and heat.
ha) protonated 1-butanamine
b) butanoic acid
c) protonated 1-pentanamine
d) pentanamide
e) pentanoic acid
2.
Which of the following pairs of reagents will undergo a nucleophilic acyl substitution reaction?
a) an amide + water
b) a carboxylic acid and a chloride ion
c) an amide + an ester
d) an acid anhydride and a chloride ion
e) an acyl chloride and a carboxylate ion
3.
Which of the following represents the correct relative reactivities?
a) acyl halide > acid anhydride > ester = carboxylic acid > amide
b) acyl halide > acid anhydride > ester > carboxylic acid > amide
c) acid anhydride > acyl halide > ester > carboxylic acid > amide
d) acyl halide = acid anhydride > ester > carboxylic acid > amide
e) acid anhydride > acyl halide > ester = carboxylic acid > amide
4.
Which of the following is the most reactive towards acid-catalyzed hydrolysis?
a) phenyl acetate
b) para-nitrophenyl acetate
c) para-methylphenyl acetate
d) para-chlorophenyl acetate
e) para-methoxyphenyl acetate
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5.
Which of the following is a semicarbazone?
a) R2C=N-OH
b) R2C=NNH-C(=O)-NH2
c) R2C=NNH2
d) R2C=NCH3
e) R2C=N-C(=O)-NHNH
6.
Which of the following compounds forms the greatest amount of hydrate in an aqueous solution?
a) propanone
b) acetone
c) acetaldehyde
d) formaldehyde
e) propanal
7.
The "desulfuration" of thioketals provides a way to convert the carbonyl group of a ketone into a
methylenebgroup. Under what conditions does desulfuration occur?
a) Heat the thioketal in a basic aqueous solution.
b) Treat the thioketal with H2O.
c) Treat the thioketal with H2 in the presence of Raney nickel.
d) Treat the thioketal with H2.
e) Heat the thioketal in an acidic aqueous solution.
8.
Which of the following is not a true statement?
a) A Grignard reagent reacts with an aldehyde to form a secondary alcohol.
b) A Grignard reagent reacts with carbon dioxide to form a carboxylic acid.
c) A Grignard reagent reacts with an acyl halide to form a secondary alcohol.
d) A Grignard reagent reacts with an ester to form a tertiary alcohol.
e) A Grignard reagent reacts with a ketone to form a tertiary alcohol.
9.
What kind of substituents are most effective in activating benzene rings toward nucleophilic
aromatic substitution reactions?
a) groups that donate electrons inductively and withdraw electrons by resonance
b) strongly electron-donating groups
c) strongly electron-withdrawing groups
d) groups that withdraw electrons inductively and donate electrons by resonance
alkyl groups
10. Which of the following compounds is an anydride
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11. Which of the following is an aldehyde
12. A nitrile can be made by dehydrating an amide. However, for this reaction to occur, the amide
must be:
a.
b.
c.
d.
e.
primary
secondary
tertiary
N-methylated
Part of a lactam
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