Download Document

Organic Chemistry, 7e
by L. G. Wade, Jr.
Chapter 7
Structure and Synthesis
of Alkenes
Christine Hermann
Radford University
Radford, VA
Copyright © 2010 Pearson Education, Inc.
7.1 Describe the geometry
around the carbon–carbon
double bond.
a.
b.
c.
d.
e.
Tetrahedral
Trigonal pyramidal
Trigonal planar
Bent
Linear
7.1 Answer
a.
b.
c.
d.
e.
Tetrahedral
Trigonal pyramidal
Trigonal planar
Bent
Linear
7.2 Give the formula for an
alkene.
a.
b.
c.
d.
e.
CnH2n-4
CnH2n-2
CnH2n
CnH2n+2
CnH2n+4
7.2 Answer
a.
b.
c.
d.
e.
CnH2n-4
CnH2n-2
CnH2n
CnH2n+2
CnH2n+4
7.3 Name CH3CH=CHCH=CH2.
a.
b.
c.
d.
e.
2,4-butadiene
1,3-butadiene
2,4-pentadiene
1,3-pentadiene
1,4-pentadiene
7.3 Answer
a.
b.
c.
d.
e.
2,4-butadiene
1,3-butadiene
2,4-pentadiene
1,3-pentadiene
1,4-pentadiene
7.4 Calculate the unsaturation
number for C6H10BrCl.
a.
b.
c.
d.
0
1
2
3
7.4 Answer
a.
b.
c.
d.
0
1
2
3
U = 0.5 [2(6) + 2 – (12)] = 1
H3C
7.5 Name
C
H
a.
b.
c.
d.
CH3
.
C
CH2CH3
Trans-2-pentene
Cis-2-pentene
Trans-3-methyl-2-pentene
Cis-3-methyl-2-pentene
7.5 Answer
a.
b.
c.
d.
Trans-2-pentene
Cis-2-pentene
Trans-3-methyl-2-pentene
Cis-3-methyl-2-pentene
The longest chain is five carbons with
numbering is left to right.
H3C
7.6 Name
CH3
C
C
H
a.
b.
c.
d.
e.
E-2-pentene
Z-2-pentene
E-3-methyl-2-pentene
Z-3-methyl-2-pentene
Z-2-methyl-2-pentene
.
CH2CH3
7.6 Answer
a.
b.
c.
d.
e.
E-2-pentene
Z-2-pentene
E-3-methyl-2-pentene
Z-3-methyl-2-pentene
Z-2-methyl-2-pentene
The longest chain is five carbons and the
highest ranking groups are on opposite
sides.
H
H
O2
7.7
C
C
Ag catalyst
H
a.
b.
c.
d.
e.
H+
CH3COOH
CH3CHO
CH3CH2OH
HOCH2CH2OH
CH3CH(OH)2
H
H2O
7.7 Answer
a.
b.
c.
d.
e.
CH3COOH
CH3CHO
CH3CH2OH
HOCH2CH2OH
CH3CH(OH)2
Ethylene oxide is formed first, followed by a
ring opening to form ethylene glycol.
7.8
H
H
Cl2
C
H
a.
b.
c.
d.
ClCH2CH2Cl
ClCH=CHCl
CH2=CH2
CH2=CHCl
C
H
NaOH
7.8 Answer
a.
b.
c.
d.
ClCH2CH2Cl
ClCH=CHCl
CH2=CH2
CH2=CHCl
Chlorine is added across the double
bond, then HCl is lost.
H
7.9
CH3
C
H2O
C
catalyst
H
a.
b.
c.
d.
H
(CH3)2CHOH
CH3CH2CH2OH
HOCH2CH2CH2OH
CH3CH(OH)CH2OH
7.9 Answer
a.
b.
c.
d.
(CH3)2CHOH
CH3CH2CH2OH
HOCH2CH2CH2OH
CH3CH(OH)CH2OH
Water adds by Markovnikov’s orientation
across the double bond.
7.10
H
CH3
C
C
H
a.
b.
c.
d.
[CH2CH(CH3)]n
[CH2CH2]n
[CH2=CH(CH3)]n
[CH2=CH2]n
H
polymerize
7.10 Answer
a.
b.
c.
d.
[CH2CH(CH3)]n
[CH2CH2]n
[CH2=CH(CH3)]n
[CH2=CH2]n
7.11 Identify the product formed
from the polymerization of
tetrafluoroethylene.
a.
b.
c.
d.
Polypropylene
Poly(vinyl chloride), (PVC)
Polyethylene
Poly(tetrafluoroethylene), Teflon
7.11 Answer
a.
b.
c.
d.
Polypropylene
Poly(vinyl chloride), (PVC)
Polyethylene
Poly(tetrafluoroethylene), Teflon
Teflon is formed from the polymerization
of tetrafluoroethylene.
7.12
H3C
CH3
C
H2
C
Pd
H
a.
b.
c.
d.
CH3CCCH3
CH2=CHCH=CH2
CH3CH=CHCH3
CH3CH2CH2CH3
H
7.12 Answer
a.
b.
c.
d.
CH3CCCH3
CH2=CHCH=CH2
CH3CH=CHCH3
CH3CH2CH2CH3
Hydrogen adds across the double bond
to form an alkane.
Br
7.13
H
Zn
H3C
C
C
H
CH3COOH
CH3 Br
a.
b.
c.
d.
(CH3)2C(Br)CH3
(CH3)2C=CHBr
(CH3)2C=CH2
(CH3)2CHCH3
7.13 Answer
a.
b.
c.
d.
(CH3)2C(Br)CH3
(CH3)2C=CHBr
(CH3)2C=CH2
(CH3)2CHCH3
Both bromides are lost to form an alkene.
7.14 Debromination of vicinal
dibromides occurs by what
mechanism?
a.
b.
c.
d.
SN1
SN2
E1
E2
7.14 Answer
a.
b.
c.
d.
SN1
SN2
E1
E2
The debromination of vicinal dibromides
occurs by an E2 mechanism.
7.15
H3C
H
C
H2SO4
CH3
OH
a.
b.
c.
d.
(CH3)2CHOSO3H
CH3CH=CH2
(CH3)2C=O
CH3CH2COOH
heat
7.15 Answer
a.
b.
c.
d.
(CH3)2CHOSO3H
CH3CH=CH2
(CH3)2C=O
CH3CH2COOH
Acid dehydrates alcohols to form alkenes.
7.16 Dehydration of alcohols
occurs by what mechanism?
a.
b.
c.
d.
SN1
SN2
E1
E2
7.16 Answer
a.
b.
c.
d.
SN1
SN2
E1
E2
The dehydration of alcohols occurs by an
E1 mechanism.
7.17 Give the products from the
catalytic cracking of alkanes.
a.
b.
c.
d.
e.
Alkanes
Alkenes
Alkynes
Alkanes + alkenes
Alkanes + alkynes
7.17 Answer
a.
b.
c.
d.
e.
Alkanes
Alkenes
Alkynes
Alkanes + alkenes
Alkanes + alkynes
7.18 Give the products from the
dehydrogenation of alkanes.
a.
b.
c.
d.
e.
Alkanes
Alkenes
Alkynes
Alkanes + alkenes
Alkanes + alkynes
7.18 Answer
a.
b.
c.
d.
e.
Alkanes
Alkenes
Alkynes
Alkanes + alkenes
Alkanes + alkynes
7.19
?
CH3CHCH2CH3
Cl
a.
b.
c.
d.
(CH3)3CO-, (CH3)3COH
CH3CH2O-, CH3CH2OH
NaI, acetone
H2, Pd
H2C
CHCH2CH3
7.19 Answer
a.
b.
c.
d.
(CH3)3CO-, (CH3)3COH
CH3CH2O-, CH3CH2OH
NaI, acetone
H2, Pd
The Hofmann product (least substituted)
is favored with a bulky base.
?
7.20
a.
b.
c.
d.
e.
CH3CH2CH2CH3
Pt, 500o C
H2, Pt
H2SO4, 150o C
NaI, acetone
NaOH
H2C
CH3CH
H2C
CHCH2CH3 +
CHCH3 +
CHCH
CH2
7.20 Answer
a.
b.
c.
d.
e.
Pt, 500o C
H2, Pt
H2SO4, 150o C
NaI, acetone
NaOH
Dehydrogenation occurs with a metal
catalyst and heat.