Sample Questions for Exam 3
1. The product, C, of the following sequence of reactions,
CH 3 CH 3 CCHO CH 3
+ CH 3CH 2CHO
OH-
H 3O + (-H2 O)
NaBH 4 CH3OH
would be: CH3 A)
CH 3CCH=CHCH2 CH 2OH CH 3 CH 3 CH 3CCH=CCH 2OH CH3 CH3 CH 3 CH 3CCH 2 CH 2CH2 OH CH3
D)
CH3 CH3 CCH2 CH2 CH 2CH 2OH CH 3 CH3 CH 3CCH2 CHCHO CH 3 CH3
B)
E)
C)
2. What would be the major product of the following reaction?
O C6 H 5CH=CHCCH 3
+ CN-
CH3CH 2OH CH3COOH
A)
O C6H5CH 2CHCCH 3
D)
O C6 H5 CH 2CH2 CCN
B)
CN O
C6 H5 CHCH 2CCH 3 CN
E)
OH C 6H5 CHCH=CCH 3 CN
C)
OH C6 H5 CH2 CH 2CCH 3 CN
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3. What would be the major product of the following reaction sequence?
O
i. LDA ii. C2H5I
O O
II
O
III
A) I
IV B) II
C) III
V D) IV
E) V
4. What synthetic strategy would accomplish the following transformation? ?
O O
A) B) C) D) E)
i) Br2 , H3 O+; ii) NaOC2 H5 , C2 H5 OH, heat i) Cl2 , FeCl3 ; ii) NaOC2 H5 , C2 H5 OH, heat i) HCN; ii) H3 O+, heat i) Br2 , h; ii) (CH3 )3 COK, (CH3 )3 COH, heat i) Br2 , H3 O+; ii) (CH3 )3 COK, (CH3 )3 COH, heat
5. Which of these is a product of the reaction of C6 H5 MgBr with
O C6 H5 CH=CHCCH 3 O A)
D)
p-C6 H5 C 6H 4
O CH=CHCCH 3
C6 H 5CH=CCCH 3 C 6H 5 OH
C6 H 5CH=CHCCH 3 C 6H 5 O
B)
E)
OC6 H5 C6 H5 CH=CHCHCH 3
C)
C6 H5 CH=CHCCH 2C 6H 5
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6. Which reagents would you use to synthesize this compound by an aldol condensation?
O C6 H5 CH=CHCC 6H 5 O
C6 H5 CH
A) B) C)
O C 6 H5 CH 2CH O
D) E)
O C6 H 5CCH 3
and
O
and
C6 H5 CH
O
C6 H5 CH 2CH
and
O
C6 H5 CCH 3
(C 6H5) 2CuLi and CH2 =CHCC 6H 5
C6 H5 CH=CHCH
and
C6H5OH
7. The aldol condensation product formed from 3-pentanone in the presence of base has the IUPAC name : A) 5-Ethyl-4-methyl-4-hepten-3-one D) 3-Ethyl-4-methyl-3-hepten-5-one B) 5-Ethyl-4-methyl-5-hepten-3-one E) 3-Ethyl-4-methyl-2-hepten-5-one C) 4-Methyl-4-nonen-3,7-dione
8. Which reagent would best serve as the basis for a simple chemical test to distinguish between 2-pentanone and 3-pentanone? A) NaOI (I2 in NaOH) D) NaHCO3 /H2 O B) Br2 /CCl4 E) Ag(NH3 )2 + C) CrO 3 /H2 SO4
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9. The Robinson annulation reaction which produces
CH3 O
uses which of the following as starting materials?
H CH2=CHC=O
CH3
O CH2=CHCCH3
CH3
+
CH2
+
O
HCHO + III
O
I
O O
II
+
CH3CH=CHCCH3 O CH3CH=CHCCH3
+
O
A) I
B)
II
IV C) III
V
D) IV E) V
10. In which of the following sequences are the compounds listed in order of decreasing acidity? A) CH3 COOH > H2 O > CH3 CH2OH > HCCH > NH3 B) CH3 CH2 OH > CH3 COOH > H2 O > HCCH > NH3 C) CH3 COOH > CH3 CH2 OH > H2 O > NH3 > HCCH D) H2 O > CH3 COOH > CH3 CH2OH > HCCH > NH3 E) CH3 CH2 OH > H2 O > CH3 COOH > HCCH > NH3
11. Which of the following would be the strongest acid?
Cl CO2H Cl CO 2H Cl CO 2H Cl
I
CO 2H Cl
II
CO2H Cl Cl
III
A) I
IV B) II
C) III
V D) IV
E) V
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12. In which of these species are all the carbon-oxygen bonds of equal length? A) Diethyl carbonate D) Propionic anhydride B) Methyl butanoate E) Pentanoic acid C) Lithium acetate
13. A compound has the molecular formula C8 H14 O4 . Its IR spectrum shows a strong absorption band near 1740 cm-1 . Its 1 H NMR spectrum consists of: triplet, singlet, quartet, 1.3 2.6 4.2
O O O O O
The most likely structure for the compound is:
O O O O O O O
I
HO2C CO2H
II
O O O O
III
A) I
B)
II
IV C) III
D) IV
V E) V
14. Which of the reactions listed below would serve as a synthesis of acetophenone, C6 H5 COCH3 ? O A)
C6 H5 Cl O H3C Cl O + C 6 H6 + (CH 3 )2 CuLi
B) C)
AlCl 3
C6 H 5
+ CH3 MgI OCH3
D) Two of these E) All of these
15. Choose the reagent(s) that would bring about the following reaction: CH3 CH2 CH2CO2 CH3 CH3 CH2 CH2 CHO A) H2 /Ni D) NaBH4 , CH3 OH B) Li/liq NH3 E) LiAlH4 , ether C) LiAlH[OC(CH3 )3 ]3
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16. Which of the following is not a method for preparing butanoic acid? A) CH3 CH2 CH2 Br + NaCN; then H3 O+, reflux B) CH3 CH2 CH2 MgBr + CO2 ; then H3 O+ C) CH3 CH2 CH2OH + CO D) CH3 CH2 CH2CO2 Et + OH /H2 O; then H3 O+ E) CH3 CH2 CH2CH2 OH + KMnO 4 /OH /H2 O/heat; then H3 O+ 17. Which of the indicated hydrogens can be replaced by alkylation? (V)
H H S H3C H3C H S H (III) H H H H
(IV)
(II) (I) A) I B)
II
C) III
D) IV
E) V
18. What is the expected product from the following reaction sequence? O O O i. NaOC2H5, C2H5OH + ? O O + ii. H3O
O O O O O O O O O O O
I
O O O
II
III
A) I
B)
IV II C) III
D) IV
E) V
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19. The product(s) of the reaction of 2 mol of ethyl butanoate with sodium ethoxide is (are): O O A) D) O OH + NaOH
O
B) C)
O O
E)
O O
O O
20. Which reagents would be used in a Mannich reaction to synthesize
O N O
I
O
O H
+ (CH3) 2NH
II
O
O H
+ (CH3) 3N
III
O
+ (CH3)3N
+ base
IV
O
H H
+ (CH3) 2NH
V
A) I B)
+ (CH3) 2NH
II C) III D) IV E) V
21. Which organic reagents would you need to make 2-ethylheptanoic acid from diethyl malonate? A) Bromoethane, 1-bromopentane, sodium ethoxide, and potassium tert-butoxide B) 3-Bromooctane and sodium ethoxide C) 3-Bromoheptane and sodium ethoxide D) 1-Bromopropane, 2-bromopentane, sodium ethoxide, and potassium tert-butoxide E) 2-Bromoheptane and potassium tert-butoxide
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22. Which of the following statements is true of the enamine,
N:
A) The enamine can be made from cyclohexanone + pyrrolidine. + B)
N
It has another resonance structure : C) It can be acylated at the -carbon of the original carbonyl compound. D) It can be alkylated. E) All of the above are true.
:
23. Which of these is not a reversible process? A) Base-promoted ester hydrolysis D) Claisen condensation B) Acid-catalyzed ester hydrolysis E) Acetal formation C) Aldol addition
24. What final product is expected when toluene is subjected to the following reaction sequence? i) KMnO 4 , NaOH; ii) H3 O+ ( product = C7 H6 O2 ); iii) SOCl2 ; iv) NH3 (product = C7 H7 NO); v) Br2 , NaOH A) C6 H5 CONH2 D) p-CH3 C6 H4NH2 B) C6 H5 CH2 NH2 E) C6 H5NH2 C) p-CH3 C6 H4 SO2NH2
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25. What would be the product of the following reaction sequence?
Cl
i)
, AlCl3 ?
ii) (CH3)2NH iii) LiBH3CN
N O
O N N
I
OH
II
III
N N
A) I
B)
IV II
C) III
V D) IV
E) V
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Answer Key
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. B B A A B D A A B A C C A D C C C A C D A E A E C
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