Download File - Pi Beta Philes!

Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) W hich of the follow ing is the best method for preparing CH3 Br?
1)
A) CH3 OH + HBr
B) CH3 OH + Br +
C) CH3 OH + Br 2
D) CH3 OH + NaBr
E) CH3 OH + Br Answ er: A
2) W hich of the follow ing alcohols w ill react most rapidly w ith the Lucas reagent (HCl, ZnCl 2 )?
A) (CH3 )3 COH
B) CH3 CH2 CH2 CH2 OH
C) (CH3 )2 CHCH2 OH
D) CH3 CHOHCH2 CH3
2)
Answ er: A
3) W hen 1-pentanol is heated w ith HCl/ZnCl2 , 1-chloropentane is the maj or organic product.
3)
This reaction proceeds through an __________ mechanism, and __________ is produced as a
byproduct.
A) SN2, H2 O
B) SN2, H2
C) SN1, H2
D) SN1, H2 O
E) E2, H2
Answ er: A
4) W hat is the maj or product of the follow ing reaction?
A)
B)
1
4)
C)
D)
E)
Answ er: A
5) W hat is the maj or product of the follow ing reaction?
A) I
B) II
C) III
5)
D) IV
Answ er: B
2
E) V
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
6) A compound (A) C4 H10 O is optically active. (A) reacts w ith HCl and ZnCl 2 (Lucas test)
6)
to form a cloudy product w ithin 10 minutes. Deduce the structure of (A).
Answ er:
7) Propose a mechanism for the follow ing reaction:
7)
Answ er:
8)
8) W hy are alcohols typically poor electrophiles?
Answ er: The hydroxide ion, a relatively strong base, is a very poor leaving group.
9) Predict the maj or product of the reaction below and provide a stepw ise mechanism
w hich accounts for its formation.
CH3 (CH2 )6 CH2 OH + HBr
Answ er:
3
9)
10)
10) Provide the structure of the maj or or ganic product in the reaction below .
Answ er:
11)
11) Provide the structure of the maj or or ganic product in the reaction below .
Answ er:
12) Name and provide the structure of the maj or or ganic product w hich results w hen
12)
(R)-3, 3-dimethyl-2-butanol is heated in the presence of HBr.
Answ er: 2-bromo-2, 3-dimethylbutane
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
13) W hich of the follow ing reagents is best used in the conversion of methyl alcohol to methyl
chloride?
A) Cl2 /CCl4
B) NaCl
C) Cl-
D) SOCl2
Answ er: D
4
E) Cl2 /h
13)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
14) Provide the structure of the maj or or ganic product of the follow ing reaction.
14)
Answ er:
15) Provide the structure of the maj or or ganic product in the reaction below .
(CH3 )2 CHCH2 OH
15)
PBr 3
Answ er: (CH3 )2 CHCH2 Br
16) Provide the structure of the maj or or ganic product of the follow ing reaction. Explain
16)
the stereochemistry w hich results in this product.
Answ er: Each of the tw o steps proceeds via an S N2 mechanism. Tw o stereochemical
inversions at the chirality center occur; thus, the product appears to have
retained the or iginal stereochemistry.
17) Provide the structure of the maj or or ganic product of the follow ing reaction.
Answ er:
5
17)
18) Provide the structure of the maj or or ganic product of the follow ing reaction.
18)
Answ er:
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
19) W hat is the product of the follow ing reaction?
19)
A)
B)
C)
D)
6
E)
Answ er: C
20) W hat is the product of the follow ing reaction?
20)
A)
B)
C)
D)
E)
Answ er: A
7
21) W hat is the maj or product of the follow ing reaction?
A) I
B) II
C) III
21)
D) IV
E) V
Answ er: E
22) W hen (R)-2-butanol is treated w ith TsCl in pyridine, the product for med is:
22)
A) a single enantiomer.
B) a mixture of diastereomers.
C) an achiral compound.
D) a racemic mixture.
E) none of the above
Answ er: A
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
23) Draw the tosylate ion and explain w hy it is a particularly good leaving group.
23)
Answ er: Extensive resonance stabilization of this ion makes it a particularly good leaving
group.
24) Provide the structure of the maj or or ganic product in the reaction below .
1. TsCl, pyridine
PhCH2 CH2 OH
2. NaCN, acetone
Answ er: PhCH2 CH2 CN
8
24)
25) Provide the structure of the maj or or ganic product of the follow ing reaction.
25)
Answ er:
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
26) W hich of the follow ing alcohols dehydrates w ith the fastest rate?
A) I
B) II
C) III
D) IV
Answ er: B
9
26)
E) V
27) W hich of the follow ing alcohols gives a rearranged carbocation w hen dehydrated?
A) I
B) II
C) III
D) IV
27)
E) V
Answ er: D
28) W hat is the product of the follow ing reaction?
A) I
B) II
28)
C) III
D) IV
E) V
Answ er: A
29) W hich of the follow ing is least likely to b e found in the product mixture w hich results w hen
2,2-dimethyl-3-pentanol is heated in phosphoric acid?
A) (Z)-4, 4-dimethyl-2-pentene
B) 2, 3-dimethyl-1-pentene
C) 2, 3-dimethyl-2-pentene
D) (E)-4, 4-dimethyl-2-pentene
E) 4, 4-dimethyl-1-pentene
Answ er: E
10
29)
30) W hat is the maj or product of the follow ing reaction?
A) I
B) II
C) III
30)
D) IV
E) V
Answ er: B
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
31) W hich of the follow ing alcohols, w hen heated w ith H2 SO4 , w ill undergo dehydration
31)
more rapidly? Explain.
Answ er: b) w ill undergo dehydration mor e rapidly because it produces a secondary
benzylic carbocation, w hich is mor e stable than secondary carbocation.
32) Starting w ith isopropyl alcohol as the only organic material, synthesize isopropyl
propyl ether.
Answ er:
11
32)
33) Propose a detailed, step-by-step mechanism for the reaction pathw ay show n below .
33)
Answ er:
34) Propose a detailed, step-by-step mechanism for the reaction pathw ay show n below .
Answ er:
12
34)
35) Draw all likely products of the follow ing reaction and circle the product you expect to
35)
predominate.
2-pentanol
H2 SO4
Answ er:
36) Draw all likely products of the follow ing reaction and circle the product you expect to
36)
predominate.
Answ er:
37) Draw all likely products of the follow ing reaction and circle the product you expect to
predominate.
Answ er:
13
37)
38) Provide the structure of the maj or or ganic product in the reaction below .
38)
Answ er:
39) Provide the structure of the maj or or ganic product of the follow ing reaction.
39)
Answ er:
40) Provide the maj or or ganic product of the reaction below .
40)
Answ er:
41) Provide the maj or or ganic product of the reaction below .
Answ er:
14
41)
42) Provide the maj or or ganic product of the reaction below .
42)
Answ er:
43)
43) Provide the maj or or ganic product of the reaction below .
Answ er:
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
44) W hich of the follow ing is a quaternary ammonium ion?
A)
B)
C)
44)
D)
Answ er: D
15
E)
45) W hat are the maj or products from the follow ing reaction?
A) I
B) II
C) III
45)
D) IV
E) V
Answ er: B
46) W hen dipentyl ether is treated w ith excess HI, through w hat type of mechanism(s) does the
major product result?
A) E1
B) SN2
C) both SN1 and SN2
D) E2
E) SN1
Answ er: B
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
47) Propose a mechanism for the follow ing reaction:
47)
Answ er:
16
46)
48) Provide the structure of the maj or or ganic product of the follow ing reaction.
48)
Answ er:
49) Provide the structure of the maj or or ganic product of the follow ing reaction.
49)
Answ er:
50) Provide the maj or or ganic product of the reaction below .
Answ er:
17
50)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
51) W hat is/are the product(s) from the follow ing reaction?
A) I
B) II
C) III
51)
D) IV
E) V
Answ er: A
52) W hat is the maj or product from the follow ing reaction?
A) I
B) II
C) III
52)
D) IV
Answ er: B
18
E) V
53) W hat is the maj or product for the follow ing reaction?
A) I
B) II
C) III
53)
D) IV
E) V
Answ er: D
54) W hat is the maj or product for the follow ing reaction?
A) I
B) II
C) III
54)
D) IV
E) V
Answ er: E
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
55) Provide the maj or or ganic product in the reaction below .
Answ er:
19
55)
56) Provide the maj or or ganic product in the reaction below .
56)
Answ er:
57) Provide the structure of the maj or or ganic product of the follow ing reaction.
57)
Answ er:
58) Provide the maj or or ganic product of the reaction below .
Answ er:
20
58)
59) Provide the maj or or ganic product of the reaction below .
59)
Answ er:
60) Provide the structure of the maj or organic product w hich results w hen naphthalene
60)
oxide undergoes rearrangement in the presence of w ater. Explain the regioselectivity of
this rearrangement.
Answ er: Naphthalene oxide can rearrange to form either 1-naphthol or 2-naphthol. The
carbocation leading to 1-naphthol is mor e stable because mor e electron
delocalization is present in w hich aromaticity is retained in the benzene ring.
61) How are certain arene oxides believed to cause cancer?
61)
Answ er: 2'-Deoxyguanosine, a component of DNA, is a nucleophile and reacts w ith
certain arene oxides to form a covalent bond. Once this part of DNA has formed a
covalent bond to another compound, the structure and replication of the DNA is
disrupted. The genetic code can no longer be transcribed properly, and this can
lead to cancerous mutations.
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
62) W hich of the follow ing is phenylthiol?
A) I
B) II
62)
C) III
D) IV
Answ er: B
21
E) V
63) W hich of the follow ing is the strongest acid?
63)
A) CH3 OCH3
B) CH3 SH
C) CH3 OH
D) CH3 NH
E) CH3 Cl
Answ er: B
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
64)
64) Provide the structure of the maj or or ganic product of the follow ing reaction.
Answ er:
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
65) W hat is the product of the follow ing reaction?
A) I
B) II
65)
C) III
D) IV
E) V
D) HOMgBr
E) CH4
Answ er: D
66) W hich of the follow ing is the strongest base?
A) H2 O
B) CH3 MgBr
66)
C) CH3 OH
Answ er: B
22
67) W hat is the product of the follow ing reaction sequence?
A) I
B) II
C) III
67)
D) IV
E) V
Answ er: D
68) W hat is the product of the follow ing reaction?
A) I
B) II
68)
C) III
D) IV
E) V
Answ er: C
69) W hich of the follow ing sequences of reactions w ould be best w hen converting cyclohexene
oxide into propylcyclohexane?
A) 1. H3 PO4 ,
2. CH3 CH2 CH2 MgBr 3. H+
B) 1. CH3 CCNa 2. H3 O+
C) 1. CH3 CH2 CH2 MgBr 2. H2 SO4 ,
3. H2 , Pt
D) 1. CH3 CH2 CH2 Li 2. HBr
E) 1. H3 O+ 2. CH3 CCNa
Answ er: C
23
69)
70) W hat is the maj or or ganic product of the follow ing reaction sequence?
70)
1. HBr
CH3 C
CCH3
2. (CH3 CH2 CH2 )2 CuLi
A) (Z)-2-bromo-2-hexene
B) 2-heptyne
C) (E)-2-bromo-2-hexene
D) (E)-3-methyl-2-hexene
E) 5-decyne
Answ er: D
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
71) The follow ing alkyl halide could not be used to form a Grignard reagent. Explain.
HO
CH2 CH2
71)
Br
Answ er: Since the alkyl halide contains an acidic proton on the oxygen, the Grignard
reagent could not be for med.
72) Show how the follow ing synthesis could be carried out.
72)
Answ er:
73) How w ould one use a Grignard-based synthesis to accomplish the follow ing
73)
transformation?
benzyl bromide (PhCH2 Br) to 3-phenyl-1-propanol
Answ er: 1.
Mg, Et 2 O
2.
ethylene oxide (oxirane)
3.
H3 O+
74) Provide the reagents necessary to accomplish the follow ing transformation.
Answ er: 1.
2.
Mg, Et 2 O
D2 O
24
74)
75) Provide the maj or or ganic product in the reaction below .
75)
Answ er:
76) Provide the sequence of r eagents needed to carry out the follow ing conversion.
CH2 C
CH
Answ er: 1.
76)
CH3 CH2 CH2 CH2 CH2 OH
NaNH2
2.
ethylene oxide
3.
H3 O+
4.
H2 (excess), Pt
77) Provide the structure of the maj or or ganic product of the follow ing reaction.
Answ er:
25
77)
78) Provide the maj or or ganic product of the reaction below .
78)
Answ er:
79) Provide the maj or or ganic product of the reaction below .
79)
Answ er:
80) Provide the maj or or ganic product of the reaction below .
Answ er:
26
80)