Transcript Which of the following are conjugated dienes? {image}

Both bonding electrons remain with one
product fragment in this kind of
reaction.
33%
33%
10%
19%
5%
1.
2.
3.
4.
5.
Homolytic bond cleavage
Heterolytic bond cleavage
Radical reaction
More than one of the above is true
None of the above
Which of the following is not a Lewis
base?
O
CH3OH
BCl3
N
(a)
33%
29%
5%
33%
(b)
1.
2.
3.
4.
A
B
C
D
(c)
(d)
Which of the following statements is
not true about free radical halogenation
of alkanes?
0%
1.
2.
10%
3.
57%
4.
33%
Bromination is more selective than
chlorination.
Chlorination under thermal conditions
(with heat) gives a statistical product
mixture.
Halogenation is more likely to occur at
less sterically hindered positions.
Hyperconjugation of the radical
intermediates helps explain preferred
reactivity.
The compound shown:
1.
2.
3.
4.
5.
Has R
stereochemistry.
Has S
stereochemistry.
Is dextrorotatory.
Is levorotatory.
It cannot be
determined without
taking the sample
into the lab and
measuring it.
19%
10%
5%
0%
67%
1
2
3
4
5
Which is the most effective method to
accomplish the transformation shown?
OH
0%
1.
38% 2.
57% 3.
5% 4.
H3O+
(1) Hg(OAc)2, H2O; (2) NaBH4
(1) BH3, ether; (2) H2O2, H2O, -OH
Any of the above methods will
work equally well.
(S)-(-)-Serine
5%
1.
2.
0%
3.
90%
5%
4.
is racemic.
rotates plane polarized light in a
clockwise direction.
rotates plane polarized light in a
counterclockwise direction.
is dextrorotatory.
Which of the following intermediates best explains
the regiochemistry of the reaction shown?
HBr, peroxides
Br
Br
(a)
19%
5%
38%
38%
(b)
1.
2.
3.
4.
A
B
C
D
.
(c)
.
(d)
Which is the best way to synthesize
2,2-dibromopropane?
33%
19%
48%
0%
1.
2.
3.
4.
propene + Br2
propene + Br2, hn
propyne + 2 HBr
propyne + 2 HBr, ROOR
Which of the following intermediates is formed in
the first step of the hydroboration/oxidation
(1) BH3, ether
reaction shown?
(2) H2O2, H2O, -OH
H H
B H
1.
2.
3.
4.
(b)
A
B
C
D
H2B OH
H
CH3
BH2
CH3
CH3
(a)
H BH2
H OH
H
CH3
(c)
(d)
5%
33%
43%
19%
1
2
3
4
What is the reactive intermediate in the
reaction of 1,3-butadiene with HBr which
results in 1,2- and 1,4- addition?
1. a cyclic bromonium
cation
2. an allylic
carbocation
3. an allylic radical
4. a dienophile
90%
10%
0%
1
0%
2
3
4
Which of the following is the most
effective way to carry out the
transformation shown?
30%
15%
5%
50%
1.
2.
3.
4.
(1) Br2, hn; (2) (CH3CH2)2CuLi
(1) NBS, hn; (2) CH3CH2MgCl
(1) Br2, hn; (2) CH3CH2MgCl
1) NBS, hn; (2) (CH3CH2)2CuLi
Identify the functional group in the
molecule shown.
O
5%
86%
0%
10%
1.
2.
3.
4.
Aldehyde
Ketone
Ester
Carboxylic acid
What is the hybridization of the nitrogen
on cocaine, which has the structure
shown below?
O
O
O
O
N
14%1.
48%2.
38%3.
sp
sp2
sp3
Which of the following is not true about
homolytic bond cleavages?
24%
48%
10%
1.
2.
3.
4.
They are exothermic.
19%
They are endothermic.
You can encourage one to happen by
heating or shining light on the sample.
More than one of the above statements
is untrue.
1
2
3
4
Which of the following does not involve
the interaction of molecules with
electromagnetic radiation?
33%
19%
33%
14%
1.
2.
3.
4.
Mass spectrometry
Infrared spectroscopy
Ultraviolet-visible spectroscopy
Nuclear magnetic resonance
spectroscopy
Which is the best method to
accomplish the transformation shown?
Br
0%
81%
14%
5%
1.
2.
3.
4.
HBr
HBr, ROOR
NBS, hn
Br2, hn
What is the formal charge on the
nitrogen on the structure shown?
5%
48%
19%
24%
5%
1.
2.
3.
4.
5.
+2
+1
0
-1
-2
O
N
O
What is the relationship between
the following compounds?
H OH
H OH
HO
HO
H
5%
29%
62%
5%
H
OH
1.
2.
3.
4.
OH
OH
HO
H
H
Isomers
Enantiomers
Diasteromers
Identical
H
OH
OH
O
H
H
OH
When an organic molecule is irradiated with
ultraviolet radiation, the energy absorbed by the
molecule corresponds to:
1.
2.
3.
4.
the amount necessary to
increase molecular motions
in functional groups.
the amount necessary to
excite electrons from one
molecular orbital to another.
the amount necessary to
“flip” the spin of atomic
nuclei.
the amount necessary to
strip a molecule of one
electron to generate a
radical cation.
57%
19%
14%
10%
1
2
3
4
Loratidine is the active ingredient in the antihistamine
Claritin®. Mass spectral analysis of loratidine shows
M+ at m/z = 382 and M+ at m/z = 384 in an approximate
ratio of 3:1 in intensity. The mass spectral data
indicates that loratidine contains:
1.
2.
3.
4.
57%
fluorine
chlorine
bromine
nitrogen
24%
14%
5%
1
2
3
4
86%
1.
2.
3.
4.
1
2
3
4
10%
1
5%
2
3
0%
4
Which of the following will react
most rapidly in an SN2 reaction?
Cl
Br
OCH3
Br
(a)
24%
5%
5%
67%
(b)
1.
2.
3.
4.
A
B
C
D
(c)
(d)
For the reaction shown below,
what is the mechanism?
Br
13%
6%
19%
63%
1.
2.
3.
4.
SN1
SN2
E1
E2
CH3OH, 