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Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Which of the following correctly describes the bond angle and hybridizations present in
formaldehyde?
A) C, sp2 ; O, sp2 ; HCO, ~120°
B) C, sp3 ; O, sp3 ; HCO, ~109.5°
C) C, sp2 ; O, sp3 ; HCO, ~120°
D) C, sp2 ; O, sp2 ; HCO, ~109.5°
E) C, sp3 ; O, sp2 ; HCO, ~109.5°
1)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
2) Would you expect the carbonyl carbon of benzaldehyde to be more or less electrophilic than that of
acetaldehyde? Explain using resonance structures.
3) Provide the proper IUPAC name for (CH3 )2CHCH2 CH2 COCHCH2 .
4) Provide the proper IUPAC name for PhCH2CH(CH3 )CH2 CH2 CHO.
5) Provide the proper IUPAC name for CH3CHOHCH2COCH2 C(CH3 )2 CH2CH3 .
6) Provide the proper IUPAC name for CH3OCH2 CH2CH(CH3 )CHO.
7) Provide the proper IUPAC name for CH3CHBrCH2COCH2 CHO.
8) Provide the structure of benzophenone.
9) Provide the structure of cyclohexanone oxime.
10) Provide the structure of the diethyl acetal of butanal.
11) Which is more soluble in water, 2-butanone or n-hexane? Explain.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
12) Which of the following represents the correct ranking in terms of increasing boiling point?
A) n-butane < 2-butanone < diethyl ether < 1-butanol
B) 2-butanone < n-butane < diethyl ether < 1-butanol
C) n-butane < diethyl ether < 2-butanone < 1-butanol
D) n-butane < diethyl ether < 1-butanol < 2-butanone
E) n-butane < 1-butanol < diethyl ether < 2-butanone
12)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
13) Provide the structure of the semicarbazone derivative of 3-pentanone.
1
13)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
14) Which compound will show an intense peak in the mass spectrum at m/z 58?
A) CH3 COCH2 CH2 CH3
B) (CH3 )3CCHO
C) CH3 CH2COCH2 CH3
D) (CH3 )2CHCOCH3
E) (CH3 )3CCOCH3
15) In the mass spectrum of 3,3-dimethyl-2-butanone, the base peak will occur at m/z:
A) 58
B) 100
C) 85
D) 84
14)
15)
E) 43
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
16) How might one distinguish an aldehyde from a ketone using IR data alone?
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
17) When a carbonyl is part of a conjugated π-network, the CO stretch:
A) has a higher frequency than in a nonconjugated system.
B) always occurs at 1710 cm-1.
C) has a lower frequency than in a nonconjugated system.
D) occurs around 2700 cm-1.
E) cannot be distinguished from the CO stretch in a nonconjugated system.
17)
18) In carbon NMR, the carbon atom of the carbonyl group in aldehydes and ketones has a chemical
shift of about:
A) 120 ppm.
B) 20 ppm.
C) 200 ppm.
D) 40 ppm.
E) 60 ppm.
18)
19) In the proton NMR spectra of aldehydes and ketones, the protons bonded to carbons adjacent to the
carbonyl group typically fall into which of the chemical shift ranges below?
A) 1.0-2.0 ppm
B) 2.0-3.0 ppm
C) 4.0-4.5 ppm
D) 7.0-8.0 ppm
E) 9.0-10.0 ppm
19)
20) The proton NMR spectrum of an unknown compound contains a triplet at 9.8 ppm. Which of the
following could be this unknown?
A) CH3 CO CH2 Ph
B) PhCHO
C) CH3 CH2CH2 CO2 H
D) (CH3 )3CCHO
E) CH3 CH2CH2 CHO
20)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
21) Provide the major organic product which results when PhCHO is treated with the
following sequence of reagents: 1. CH3 CH2 MgBr; 2. H3 O+; 3. Na2 Cr2O7 , H2 SO4 .
2
21)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
22) By which single reaction can benzene be readily converted into acetophenone?
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
23) What reagents can be used to convert 1-hexyne into 2-hexanone?
A) 1. Sia2 BH; 2. H2 O2, NaOH
B) 1. H2 , Ni; 2. Na2 Cr2 O7, H2SO4
C) 1. CH3 MgBr; 2. CO2
D) Hg2+ , H2 SO4 , H2 O
23)
E) 1. O3; 2. (CH3 )2 S
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
24) What reagent can be used to convert benzophenone into triphenylmethanol?
24)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
25) What reagent can be used to convert 2-methylbutan-1-ol into 2-methylbutanal?
A) Na2 Cr2 O7
B) PCC
C) KMnO 4
D) O3
E) LiAlH4
25)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
26) Beginning with sodium acetylide (NaCCH), propose a three-step synthesis of hexanal.
26)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
27) Beginning with 1,3-dithiane, propose a synthesis of 4-heptanone.
28) Provide the major organic product which results in the reaction shown below.
29) Provide the major organic product which results when PhCH2CH2 CO2 H is treated with excess butyllithium
followed by H3O+ .
30) How might one prepare 4-heptanone from CH3 CH2 CH2 CN in two steps?
31) Provide the major organic product which results when (CH3 )2CHCH2 CH2 COCl is treated with
LiAlH[OC(CH3 )3]3 .
3
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
32) Which of the following describes a synthesis of an aldehyde?
A) treatment of an alkene with Sia2 BH
B) hydrogenation of an acid chloride using Pd/BaSO4 /S as a poisoned catalyst
C) reaction of a primary alcohol with Na2 Cr2 O7
D) reaction of a ketone with ozone
E) none of the above
32)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
33) Provide a detailed, stepwise mechanism for the acid-catalyzed reaction of 2-butanone
with ethylene glycol (HOCH2 CH2 OH) to produce an acetal.
33)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
34) Provide a detailed, stepwise mechanism for the acid-catalyzed condensation reaction between benzaldehyde
and methylamine.
35) Provide a detailed, stepwise mechanism for the acid-catalyzed condensation reaction between cyclohexanone
and H2 NOH.
36) Provide the major organic product which results when PhCHOHCH3 is treated with PCC.
37) Provide the major organic product which results when pentanal is subjected to the following sequence of steps:
1. PhMgBr; 2. H3O+ ; 3. PCC
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
38) When the carbonyl group of a neutral ketone is protonated,:
A) the resulting species is activated toward nucleophilic attack.
B) the resulting species has a positive charge.
C) the resulting species becomes more electrophilic.
D) subsequent nucleophilic attack on the resulting species is said to occur under acid-catalyzed
conditions.
E) all of the above.
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
39) Draw two major resonance forms of the cation which results when cyclohexanone's
carbonyl group is protonated.
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
40) Propose a synthesis of 4-phenylbutan-2-ol from 3-phenylpropanal.
41) Propose a synthesis of 3-methylhept-4-yn-3-ol from but-1-yne.
42) Provide a detailed, stepwise mechanism for the base-catalyzed hydration of 2-butanone.
4
39)
38)
43) Why are the equilibrium constants for hydration of aldehydes typically greater than those of ketones?
44) Provide the structure of the hydrate of cyclopentanone.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
45) Consider the equilbrium of each of the carbonyl compounds with HCN to produce cyanohydrins.
Which is the correct ranking of compounds in order of increasing Keq for this equilbrium?
A) H2CO < cyclohexanone < CH3CHO < 2-methylcyclohexanone
B) 2-methylcyclohexanone < cyclohexanone < CH3 CHO < H2CO
C) cyclohexanone < 2-methylcyclohexanone < H2 CO < CH3 CHO
D) cyclohexanone < 2-methylcyclohexanone < CH3 CHO < H2CO
E) CH3 CHO < 2-methylcyclohexanone < cyclohexanone < H2CO
45)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
46) Provide the structure of the compound which results when HCN adds to pentanal.
46)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
47) Conversion of aldehydes and ketones to imines is an acid-catalyzed process. Explain why this conversion is
actually hindered by the presence of too much acid.
48) Provide the major organic product of the reaction of aniline with 3-pentanone.
49) When H2 NCH2 CH2 CH2 CH2COCH3 is heated in the process of an acid catalyst, a reaction occurs. The product
has the formula C6 H11N. Provide the structure of this product.
50) Provide the structure of the major organic product which results when benzaldehyde reacts with
hydroxylamine in the presence of acid.
51) Provide the structure of the compound which reacts with a ketone to form its hydrazone derivative.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
52) Which of the following is also known as a Schiff base?
A) a cyanohydrin
B) a hydrate
C) sodium hydroxide
D) an imine
E) an aldehyde
5
52)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
53) Propose a sequence of steps to carry out the following conversion.
53)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
54) Why do acetal-forming reactions that use ethylene glycol have more favorable equilbrium
constants than those using methanol?
A) The ethylene acetal can serve as a protecting group.
B) They are more favorable on enthalpy grounds.
C) They are more favorable on entropy grounds.
D) Ethylene glycol is acidic and catalyzes the reaction.
E) Ethylene glycol reacts more rapidly.
54)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
55) When HOCH2 CH2 CH2 CH2COCH2 CH2 CH2CH2 OH is heated in the presence of an acid
catalyst, a reaction occurs. This product has the formula C9 H16O2 . Provide the structure of
this product.
55)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
56) Propose a sequence of steps to carry out the following conversion.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
57) What intermediate occurs when a ketone undergoes a Wolff-Kishner reduction?
A) a hydrated aldehyde
B) a cyanohydrin
C) a carboxylate
D) a hydrazone
E) a semicarbazone
6
57)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
58) Which would be more appropriate as the reduction in the following sequence, a Clemmensen or a
Wolff-Kishner? Explain.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
59) The reagent which converts a carbonyl group of a ketone into a methylene group is:
A) NaBH4 , CH3 CH2 OH
B) LiAlH[OC(CH3 )3]3
C) LiAlH4
D) Na, NH3 , CH3 CH2 OH
E) Zn(Hg), conc. HCl
59)
60) Acetals will react with:
A) CH3 CH2MgBr
B) NaBH4
C) H3O⊕
60)
D) PhLi
E) NaOCH3
61) The double bond between carbon and oxygen is similar to an alkene CC, except that the carbonyl
double bond is:
A) longer and weaker.
B) longer and stronger.
C) longer.
D) shorter and stronger.
E) shorter and weaker.
61)
62) The positively polarized carbon atom of a carbonyl group acts as:
A) an electrophile and a Lewis base.
B) both a Lewis acid and a Lewis base.
C) a nucleophile and a Lewis acid.
D) a nucleophile and a Lewis base.
E) an electrophile and a Lewis acid.
62)
63) Another name for β-methoxybutyraldehyde is:
A) 2-methoxypropanal.
B) 3-methoxypropanal.
C) 3-methoxybutanal.
D) 2-methoxypentanal.
E) 2-methoxybutanal.
63)
7
64) Which of the following compounds is most soluble in water?
A) cyclohexanone
B) 2-butanone
C) 3-butanone
D) benzophenone
E) acetone
64)
65) What name is given to the linear polymer which contains many formaldehyde units?
A) trioxane
B) polyalal
C) polyacetaldehyde
D) formalin
E) paraformaldehyde
65)
66) The strongest absorptions in the UV spectra of aldehydes and ketones are ones which result from
__________ electronic transitions.
A) π to σ*
B) σ to π*
C) π to π*
D) σ to σ*
E) n to π*
66)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
67) Propose a synthesis of 3-heptanone from propanal.
67)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
68) Name the compound generated when 1-methylcyclohexene is subjected to O3 followed by dimethyl sulfide.
69) Name the compound generated when ethylbenzene is treated with CO, HCl, AlCl3 , and CuCl.
70) What organic compound is generated when PhCOCl is treated with (CH3CH2 CH2 )2 CuLi?
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
71) Provide the structure of cyclohexanecarbaldehyde.
71)
72) Provide the structure of 4-oxohexanoic acid.
72)
73) Trioxane is a cyclic trimer of formaldehyde that can be converted to formaldehyde upon
heating. Show this reaction.
73)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
74) Which of the following compounds would show only one triplet in its off resonance decoupled
13C NMR spectrum?
A) 2-pentanone
B) acetone
C) 3-pentanone
D) butanal
E) pentanal
8
74)
75) Which of the following transitions is usually observed in the UV spectra of ketones?
A) σ to n
B) n to π*
C) n to σ*
D) n to π
E) σ to σ*
75)
76) Oxidation of a 1° alcohol with chromic acid results in the production of __________.
A) an ether
B) an ester
C) a ketone
D) an aldehyde
E) none of the above
76)
77) Oxidation of a 2° alcohol with chromic acid results in the production of __________.
A) an ether
B) a ketone
C) an ester
D) an aldehyde
E) none of the above
77)
78) Oxidation of a 3° alcohol with chromic acid results in the production of __________.
A) an aldehyde
B) a ketone
C) an ester
D) an ether
E) none of the above
78)
79) Oxidation of a 1° alcohol with pyridinium chlorochromate results in the production of __________.
A) a ketone
B) an ether
C) an ester
D) an aldehyde
E) none of the above
79)
80) Treatment of a nitrile with a Grignard reagent followed by hydrolysis results in __________.
A) an ester
B) a ketone
C) an ether
D) an alcohol
E) an aldehyde
80)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
81) What compound is produced when 1,3-dithiane is subjected to the following sequence of
reagents: 1. n-BuLi 2. CH3CH2 Br 3. n-BuLi 4. (CH3 )2 CHCH2CH2 I 5. HgCl2, H3O+ ?
81)
82) Why is (CH3 )3CCHO not available via a 1,3-dithiane based synthesis?
82)
83) What compound is produced when 1,3-dithiane is subjected to the following sequence of
reagents: 1. n-BuLi 2. (CH3)3 CCH2 CH2 CH2 I 3. HgCl2 , H3 O+ ?
83)
9
84) Provide the IUPAC name for the following compound.
84)
85) Provide the IUPAC name for (CH3 )3 CCH2 CHClCH2 CHO.
85)
86) Rank the following compounds in order of their propensity to become a hydrate in water
(ie, start with the least easy to hydrate: CH3COCH2 CH3 , H2 CO, Cl3 CCHO, and
86)
CH3 CH2CHO.
87) Give the structure of the acyclic compound from which the following imine was formed.
87)
88) Provide the major organic product of the following reaction.
88)
89) Provide the major organic product of the following reaction.
89)
90) Provide the major organic product of the following reaction.
90)
10
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
91) Which of the following reactions will not yield a ketone product?
A)
B)
C)
D)
E)
11
91)
92) Which series of reactions described below, if any, will result in the formation of
2-methylpentan-3-one starting with 1-propanol?
A) 1.
2.
Na2 Cr2 O7/H2 SO4 and heat
SOCl2
3.
2 (CH3 )2 CHMgBr/ diethly ether
4.
H3O+
B) 1.
2.
(CH3 )2CHMgBr/ diethyl ether
dilute H3 O+
3.
PCC
C) 1.
2.
Na2 Cr2 O7/H2 SO4 and heat
(CH3 )2CHMgBr/ diethyl ether
3.
dilute H3 O+
4.
LiAlH4
PCC
(CH3 )2CHLi/ diethyl ether
D) 1.
2.
3.
dilute H3 O+
4.
Na2 Cr2 O7/H2 SO4 and heat
E) none of the above
12
92)
93) What would be the product of the following reaction?
93)
A)
B)
C)
D)
E)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
94) Give an IUPAC name to the following compound. Be sure to include configurational
information in the name.
13
94)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
95) Which series of reactions described below will result in the formation of compound A, starting with
compound B?
A) 1.
2.
3.
4.
B) 1.
3.
HO-(CH2 )2-OH /trace H3O+
DMSO (COCl2)/Et3 N, CH2 Cl2
MgBr-(CH2)2 -CH3 /diethylether
work-up with H3 O+
4.
PCC
SOCl2
LiCu-((CH2 )2-CH3 )2
5.
work-up with H3 O+
C) 1.
2.
Na2 Cr2 O7/H2 SO4
SOCl2
3.
2 MgBr-(CH2 )2 -CH3 /diethylether
4.
work-up with H3 O+
D) both A and B
E) both B and C
14
95)
Answer Key
Testname: CO_ALL
1) A
2) The carbonyl carbon of benzaldehyde would be less electrophilic. Delocalization reduces its partial positive charge as
seen in the resonance forms below.
3)
4)
5)
6)
7)
8)
9)
6-methylhept-1-en-3-one
4-methyl-5-phenylpentanal
2-hydroxy-6,6-dimethyl-4-octanone
4-methoxy-2-methylbutanal
5-bromo-3-oxohexanal
PhCOPh
10) CH3 CH2CH2 CH(OCH2CH3 )2
11) 2-Butanone is more soluble in water. The polarization of the carbonyl group gives the molecule a permanent dipole
moment. More importantly, the hydrogens of water can hydrogen bond with the carbonyl oxygen.
12) C
13)
14) A
15) E
16) The aldehyde has two C-H stretches at 2700 and 2800 cm-1.
17) C
18) C
19) B
20) E
21) PhCOCH2CH3
22) CH3 COCl, AlCl3 - a Friedel-Crafts acylation reaction
23) D
24) PhMgBr followed by acidic work up
25) B
15
Answer Key
Testname: CO_ALL
26) 1. CH3 CH2 CH2CH2 Br
2. Sia2 BH
3. H2 O2 , NaOH
27) 1. BuLi
2. CH3 CH2 CH2Br
3. BuLi
4. CH3 CH2 CH2Br
5. HgCl2 , H3 O+
28)
29) PhCH2CH2 COCH2 CH2CH2 CH3
30) 1. CH3 CH2 CH2MgBr
2. H3 O+
31) (CH3 )2CHCH2 CH2 CHO
32) B
33)
16
Answer Key
Testname: CO_ALL
34)
35)
36) PhCOCH3
37) PhCOCH2CH2 CH2 CH3
38) E
39)
40) 1. CH3 MgBr
2. H3 O+
41) 1. NaNH2
2. CH3 COCH2CH3
3. H3 O+
42)
17
Answer Key
Testname: CO_ALL
43) The carbonyl group of an aldehyde is stabilized by only one electron donating alkyl group. Therefore, its carbonyl
group has more partial positive charge than that of a ketone. Aldehydes are more electrophilic and less stable than
ketones.
44)
45) B
46)
47) At very low pH, much more of the amine is protonated and can no longer function as a nucleophile.
48)
49)
50)
51) H2NNH2
52) D
53) 1. HOCH2 CH2 OH, H+
2. NaNH2
3. CH3 I
4. H3 O+
5. NaBH4 or LiAlH4
54) C
55)
56) 1. HOCH2 CH2 OH, H+
2. CH3 CH2 CH2MgBr
3. H3 O+
57) D
18
Answer Key
Testname: CO_ALL
58) Wolff-Kishner. The acidic conditions of the Clemmensen would remove the protecting group causing reduction of the
aldehyde as well.
59) E
60) C
61) D
62) E
63) C
64) E
65) E
66) C
67) 1. CH3 CH2 CH2CH2 MgBr, Et2 O
2. H3 O+
3. Na2 Cr2O7 , H2 SO4
68) 6-oxoheptanal
69) p-ethylbenzaldehyde
70) PhCOCH2CH2 CH3
71)
72)
73)
74) C
75) B
76) E
77) B
78) E
79) D
80) B
81) CH3 CH2COCH2 CH2 CH(CH3)2
82) A dithiane based synthesis of (CH3)3 CCHO would require the dithiane anion to react with (CH3 )3CBr in an SN2
process. Tertiary halides do not undergo SN2 reactions because they are excessively hindered.
83) (CH3 )3CCH2CH2 CH2 CHO
84) 6-hydroxy-4-nonanone or 6-hydroxynonan-4-one
85) 3-chloro-5,5-dimethylhexanal
19
Answer Key
Testname: CO_ALL
86) CH3 COCH2 CH3 < CH3 CH2 CHO < H2CO < Cl3 CCHO
87)
88)
89)
90)
91) E
92) D
93) D
94) (Z)-4-oxo-2-pentenal or (Z)-4-oxopent-2-enal
95) A
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