CHM 3342
Third Exam
Fall 2004
8 points each
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Which compound would be expected to show intense IR absorption at 2250 cm-1?
A) CH3CH2CH2CO2H
B) (CH3)2CHCN
C) (CH3)2CHCH2OH
D) CH3CH2CH2CONH 2
1)
2) Which of the following species is the least nucleophilic?
A) BF 3
B) CH3OC) CN-
2)
D) (CH3)3N
E) H2O
3) Which of the compounds below undergoes solvolysis in aqueous ethanol most rapidly?
A) methyl iodide
B) 3-iodo-3-methylpentane
C) cyclohexyl bromide
D) isopropyl chloride
E) 3-chloropentane
3)
4) Which of the following compounds will undergo an S N2 reaction most readily?
A) (CH3)2CHI
B) (CH3)2CHCH2CH2CH2I
C) (CH3)3CCl
D) (CH3)3CCH2I
E) (CH3)2CHCH2CH2CH2Cl
4)
5) Predict the two most likely mechanisms which occur when 2-iodohexane is heated in ethanol.
A) E1 and E2
B) SN2 and E2
C) E2 and SN1
D) E1 and SN1
E) SN2 and SN1
5)
6) In which of the following mechanisms (SN1, SN2, E1, E2) are alkenes the major reaction
products?
A) SN1 only
B) E2 only
C) E1 only
D) SN2 only
E) both E1 and E2
6)
7) How many rings+multiple bonds are implied by the molecular formula C5H5NO2?
A) 0
B) 1
C) 2
D) 3
E) 4
7)
1
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
8) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
9) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
10) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
11) Provide an acceptable name for the compound shown below.
12) Provide the structure of the major organic product in the reaction below.
13) Provide the structure of the major organic product in the reaction below.
14) Provide the structure of the major organic product in the following reaction.
2
15) Provide the structure of the major organic product which results in the following reaction.
16) List the following compounds in order of increasing reactivity in an SN1 reaction.
CH3Br, CH3CH2CH2I, (CH 3)3CI, CH3CHBrCH3, CH3CHICH3
17) Draw an acceptable structure for 1,2-dimethylcyclohexene.
18) Draw all likely alkene products in the following reaction and circle the product you expect to predominate.
19) Draw all likely products of the following reaction and circle the product you expect to predominate.
20) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
21) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
22) Draw the major organic product generated in the reaction below. Pay particular attention to regio- and
stereochemical detail.
23) Deduce a possible structure for the compound with the IR absorptions below.
C5H8O: <3000, 1750 cm-1
3
24) Consider the reaction of (CH3)3CO- with iodomethane. Will the reaction rate increase, decrease, or remain
the same if the concentration of iodomethane is increased? Explain.
25) Provide the major organic product of the reaction below and a detailed, stepwise mechanism which
accounts for its formation.
4
Answer Key
Testname: CHM3342EXAM3F04
1)
2)
3)
4)
5)
6)
7)
8)
B
A
B
B
D
E
E
9)
10)
11) cis-1, 2-dichlorocyclopentane
12)
13)
14)
15)
16) CH3Br < CH 3CH2CH2I < CH3CHBrCH3 < CH 3CHICH3 < (CH3)3CI
17)
5
Answer Key
Testname: CHM3342EXAM3F04
18)
19)
20)
21)
22)
23) cyclopentanone
24) This is an SN2 reaction with a rate = k[(CH3)3CO-] [CH 3I]. The reaction rate will increase as [CH3I] increases.
25)
6