CHE-300Review

1
CHE-300 Review nomenclature syntheses reaction
s mechanisms
2
Alkanes Alkyl halides Alcohols Ethers Alkenes con
jugated dienes Alkynes Alicyclics Epoxides
3
Alkanes Nomenclature Syntheses 1. reduction
of alkene (addition of hydrogen) 2. reduction
of an alkyl halide a) hydrolysis of a
Grignard reagent b) with an active metal and
acid 3. Corey-House Synthesis Reactions 1.
halogenation 2. combustion (oxidation) 3.
pyrolysis (cracking)
4
Alkanes, nomenclature

CH3 CH3CH2CH2CH2CH2CH3
CH3CHCH2CH2CH3 (n-hexane)
(isohexane)
n-hexane 2-methylpentane
CH3 CH3 CH3CH2CHCH2CH3 CH3CCH2
CH3 (no common name)
CH3 3-methylpentane
(neohexane) 2,2-dimethylbutane
CH3 CH3CHCHCH3 CH3 (no common
name) 2,3-dimethylbutane
5

• Alkanes, syntheses
• 1. Addition of hydrogen (reduction).
• C C H2 Ni, Pt, or Pd ?
  C C
• 
  H H
• Requires catalyst.
• CH3CHCHCH3 H2, Ni ? CH3CH2CH2CH3
• 2-butene n-butane

6

• Reduction of an alkyl halide
• a) hydrolysis of a Grignard reagent (two
  steps)
• i) RX Mg ? RMgX (Grignard
  reagent)
• ii) RMgX H2O ? RH Mg(OH)X
• SB SA WA WB
• CH3CH2CH2-Br Mg ? CH3CH2CH2-MgBr
• n-propyl bromide n-propyl magnesium bromide
• CH3CH2CH2-MgBr H2O ? CH3CH2CH3
  Mg(OH)Br
• 
  propane

7

• with an active metal and an acid
• RX metal/acid ? RH
• active metals Sn, Zn, Fe, etc.
• acid HCl, etc. (H)
• CH3CH2CHCH3 Sn/HCl ? CH3CH2CH2CH3
  SnCl2
• Cl
• sec-butyl chloride n-butane
• CH3
  CH3
• CH3CCH3 Zn/H ? CH3CHCH3 ZnBr2
• Br
• tert-butyl bromide isobutane

8
3. Corey-House Synthesis CH3
CH3
CH3 CH3CH-Br Li ? CH3CH-Li CuI
? (CH3CH)2-CuLi isopropyl bromide
CH3 CH3 (CH3CH)2-CuLi
CH3CH2CH2-Br ? CH3CH-CH2CH2CH3

2-methylpentane
(isohexane) mechanism SN2 Note the RX should
be a 1o or methyl halide for the best yields of
the final product.
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Alkanes, reactions 1. Halogenation R-H
X2, heat or hv ? R-X HX a) heat or
light required for reaction. b) X2 Cl2 gt Br2
? I2 c) yields mixtures ? d) H 3o gt 2o gt 1o
gt CH4 e) bromine is more selective f) free
radical substitution
10
CH3CH2CH2CH3 Br2, hv ? CH3CH2CH2CH2-Br
2 n-butane n-butyl
bromide CH3CH2CHCH3 98

Br sec-butyl bromide
CH3
CH3 CH3CHCH3 Br2, hv ? CH3CHCH2-Br
lt1 isobutane isobutyl bromide


CH3
CH3CCH3 99
Br tert-butyl bromide
11
Alkyl halides nomenclature syntheses 1. from
alcohols a) HX b) PX3 2.
halogenation of certain alkanes 3. addition of
hydrogen halides to alkenes 4. addition of
halogens to alkenes 5. halide exchange for
iodide reactions 1. nucleophilic
substitution 2. dehydrohalogenation 3.
formation of Grignard reagent 4. reduction
12
Alkyl halides, nomenclature CH3
CH3 CH3CHCH2CHCH3 CH3CCH3
Br
I 2-bromo-4-methylpentane tert-butyl
iodide 2-iodo-2-methylpropane
2o 3o CH3 Cl-CHCH2CH3 sec-butyl
chloride 2-chlorobutane 2o
13

• Alkyl halides, syntheses
• 1. From alcohols
• With HX
• R-OH HX ? R-X
  H2O
• i) HX HCl, HBr, HI
• ii) may be acid catalyzed (H)
• iii) ROH 3o gt 2o gt CH3 gt 1o (3o/2o SN1
  CH3/1o SN2)
• iv) rearrangements are possible except with most
  1o ROH

14
CH3CH2CH2CH2-OH NaBr, H2SO4, heat
? CH3CH2CH2CH2-Br n-butyl alcohol
(HBr) n-butyl bromide 1-butanol 1-bromo
butane CH3 CH3 CH3CCH3
HCl ? CH3CCH3 OH Cl
tert-butyl alcohol tert-butyl chloride
2-methyl-2-propanol 2-chloro-2-methylpropane
CH3-OH HI, H,heat ? CH3-I
methyl alcohol methyl iodide
methanol iodomethane
15
from alcohols b) PX3 i) PX3 PCl3, PBr3,
P I2 ii) ROH CH3 gt 1o gt 2o iii) no
rearragements CH3CH2-OH P, I2 ?
CH3CH2-I ethyl alcohol ethyl iodide
ethanol iodoethane CH3

CH3 CH3CHCH2-OH PBr3 ? CH3CHCH2-Br
isobutyl alcohol isobutyl bromide
2-methyl-1-propanol 1-bromo-2-methylprop
ane
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• Halogenation of certain hydrocarbons.
• R-H X2, ? or h? ? R-X
  HX
• (requires ? or h? Cl2 gt Br2 (I2 NR)
  3ogt2ogt1o)
• ?yields mixtures! ? In syntheses,
  limited to those hydrocarbons that yield only one
  monohalogenated product.
• CH3 CH3
• CH3CCH3 Cl2, heat ? CH3CCH2-Cl
• CH3
  CH3
• neopentane neopentyl chloride
• 2,2-dimethylpropane 1-chloro-2,2-dimethy
  lpropane

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• Halide exchange for iodide.
• R-X NaI, acetone ? R-I
  NaX ?
• i) R-X R-Cl or R-Br
• ii) NaI is soluble in acetone, NaCl/NaBr are
  insoluble.
• CH3CH2CH2-Br NaI, acetone ?
  CH3CH2CH2-I
• n-propyl bromide n-propyl idodide
• 1-bromopropane 1-idodopropane
• iii) SN2 R-X should be 1o or CH3

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• Reactions of alkyl halides
• Nucleophilic substitution ?Best with 1o or
  CH3!!!!!!
• R-X Z- ? R-Z X-
• Dehydrohalogenation
• R-X KOH(alc) ? alkene(s)
• Preparation of Grignard Reagent
• R-X Mg ? RMgX
• Reduction
• R-X Mg ? RMgX H2O
  ? R-H
• R-X Sn, HCl ? R-H

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1. Nucleophilic substitution R-X OH-
? ROH X- alcohol R-X H2O
? ROH HX alcohol R-X
OR- ? R-O-R X- ether R-X
-C?CR ? R-C?CR
X- alkyne R-X I- ? R-I
X- iodide R-X CN- ?
R-C?N X- nitrile R-X NH3
? R-NH2 HX primary amine R-X
NH2R ? R-NHR HX secondary
amine R-X SH- ? R-SH
X- thiol R-X SR ? R-SR
X- thioether Etc. Best when R-X is CH3 or
1o! SN2
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• 2. dehydrohalogenation of alkyl halides
• C C KOH(alc.) ? C C
  KX H2O
• H X
• RX 3o gt 2o gt 1o
• no rearragement ?
• may yield mixtures ?
• Saytzeff orientation
• element effect
• isotope effect
• rate k RX KOH
• Mechanism E2

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CH3CHCH3 KOH(alc) ? CH3CHCH2
Br isopropyl bromide propylene CH3CH2CH2CH2-Br
KOH(alc) ? CH3CH2CHCH2
n-butyl bromide 1-butene CH3CH2CHCH3
KOH(alc) ? CH3CH2CHCH2 Br
1-butene 19 sec-butyl bromide
CH3CHCHCH3 2-butene 81
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• 3. preparation of Grignard reagent
• CH3CH2CH2-Br Mg ? CH3CH2CH2-MgBr
• n-propyl bromide n-propyl magnesium bromide
• reduction
• CH3CH2CH2-Br Mg ? CH3CH2CH2-MgBr
• CH3CH2CH2-MgBr H2O ? CH3CH2CH3
  Mg(OH)Br
• 
  propane
• CH3CH2CHCH3 Sn/HCl ? CH3CH2CH2CH3
  SnCl2
• Cl
• sec-butyl chloride n-butane

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Alcohols nomenclature syntheses 1.
oxymercuration-demercuration 2.
hydroboration-oxidation 3. 4. hydrolysis of
some alkyl halides reactions 1. HX 2.
PX3 3. dehydration 4. as acids 5. ester
formation 6. oxidation
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Alcohols, nomenclature CH3
CH3 CH3CHCH2CHCH3 CH3CCH3
OH
OH 4-methyl-2-pentanol tert-butyl alcohol
2-methyl-2-propanol 2o
3o CH3 HO-CHCH2CH3 CH3CH2CH2-OH sec
-butyl alcohol n-propyl alcohol
2-butanol 1-propanol 2o
1o
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• Alcohols, syntheses
• 1. oxymercuration-demercuration
• Markovnikov orientation.
• 100 yields. ?
• no rearrangements ?
• CH3CH2CHCH2 H2O, Hg(OAc)2 then NaBH4 ?
• CH3CH2CHCH3
• 
  OH

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• 2. hydroboration-oxidation
• Anti-Markovnikov orientation. ?
• 100 yields. ?
• no rearrangements ?
• CH3CH2CHCH2 (BH3)2 then H2O2, NaOH ?
• CH3CH2CH2CH2-OH
• 
  

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Reaction of alcohols 1. with HX
R-OH HX ? R-X H2O a) HX
HI gt HBr gt HCl b) ROH 3o gt 2o gt CH3
gt 1o SN1/SN2 c) May be acid catalyzed d)
Rearrangements are possible except with most 1o
alcohols.
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CH3CH2CH2CH2-OH NaBr, H2SO4, heat
? CH3CH2CH2CH2-Br n-butyl alcohol
(HBr) n-butyl bromide 1-butanol 1-bromo
butane CH3 CH3 CH3CCH3
HCl ? CH3CCH3 OH Cl
tert-butyl alcohol tert-butyl chloride
2-methyl-2-propanol 2-chloro-2-methylpropane
CH3-OH HI, H,heat ? CH3-I
methyl alcohol methyl iodide
methanol iodomethane
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• With PX3
• ROH PX3 ?
  RX
• PX3 PCl3, PBr3, P I2
• No rearrangements
• ROH CH3 gt 1o gt 2o
• CH3
  CH3
• CH3CCH2-OH PBr3 ?
  CH3CCH2-Br
• CH3
  CH3
• neopentyl alcohol
  2,2-dimethyl-1-bromopropane

?
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• Dehydration of alcohols
• C C acid, heat ? C C
  H2O
• H OH
• ROH 3o gt 2o gt 1o
• acid is a catalyst
• rearrangements are possible ?
• mixtures are possible ?
• Saytzeff
• mechanism is E1

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CH3CH2-OH 95 H2SO4, 170oC ?
CH2CH2 CH3 CH3 CH3CCH3
20 H2SO4, 85-90oC ? CH3CCH2
OH CH3CH2CHCH3 60 H2SO4, 100oC ?
CH3CHCHCH3 OH
CH3CH2CHCH2 CH3CH2CH2CH2-OH H, 140oC ?
CH3CH2CHCH2 rearrangement! ?
CH3CHCHCH3
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• As acids.
• With active metals
• ROH Na ? RONa ½ H2 ?
• CH3CH2-OH K ? CH3CH2-O-K H2
• With bases
• CH4 lt NH3 lt ROH lt H2O lt HF
• ROH NaOH ? NR!
• CH3CH2OH CH3MgBr ? CH4
  Mg(Oet)Br

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• Ester formation.
• CH3CH2-OH CH3CO2H, H ?
  CH3CO2CH2CH3 H2O
• CH3CH2-OH CH3COCl ?
  CH3CO2CH2CH3 HCl
• CH3-OH CH3SO2Cl ? CH3SO3CH3
  HCl
• Esters are alkyl salts of acids.

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• Oxidation
• Oxidizing agents KMnO4, K2Cr2O7, CrO3, NaOCl,
  etc.
• Primary alcohols
• CH3CH2CH2-OH KMnO4, etc. ?
  CH3CH2CO2H
• 
  carboxylic acid
• Secondary alcohols
  
• OH
  O
• CH3CH2CHCH3 K2Cr2O7, etc. ?
  CH3CH2CCH3
• 
  
  ketone
• Teriary alcohols
• no reaction.

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Primary alcohols ONLY can be oxidized to
aldehydes CH3CH2CH2-OH C5H5NHCrO3Cl ?
CH3CH2CHO pyridinium chlorochromate
aldehyde
or CH3CH2CH2-OH K2Cr2O7,
special conditions ?
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Ethers nomenclature syntheses 1. Williamson
Synthesis 2. alkoxymercuration-demercuration r
eactions 1. acid cleavage
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Ethers R-O-R or R-O-R Nomenclature
simple ethers are named alkyl alkyl
ether dialkyl ether if symmetric

CH3 CH3 CH3CH2-O-CH2CH3 CH3
CH-O-CHCH3 diethyl ether
diisopropyl ether
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1. Williamson Synthesis of Ethers
R-OH Na ? R-O-Na ?
R-O-R R-OH HX ?
R-X (CH3)2CH-OH Na ?
(CH3)2CH-O-Na ? CH3CH2CH2-O-CH(CH3)2 CH3CH2
CH2-OH HBr ? CH3CH2CH2-Br
isopropyl n-propyl ether note the alkyl
halide is primary! ?
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CH3CH2CH2-OH Na ? CH3CH2CH2-ONa
? CH3CH2CH2-O-CH(CH3)2 (CH3)2CH-OH
HBr ? (CH3)2CH-Br
2o The product of this attempted
Williamson Synthesis using a secondary alkyl
halide results not in the desired ether but in an
alkene! The alkyl halide in a Williamson
Synthesis must beCH3 or 1o!
?
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• 2. alkoxymercuration-demercuration
• Markovnikov orientation.
• 100 yields. ?
• no rearrangements ?
• CH3CHCH2 CH3CHCH3, Hg(TFA)2 then NaBH4 ?
• OH
• 
  CH3 CH3
• CH3CH-O-CHCH3
• 
  diisopropyl ether
• 
  
• Avoids the elimination with 2o/3o RX in
  Williamson Synthesis.

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• Reactions, ethers
• Acid cleavage.
• R-O-R (conc) HX, heat ? R-X
  R-X
• CH3CH2-O-CH2CH3 HBr, heat ? 2
  CH3CH2-Br

42
Alkenes nomenclature syntheses 1.
dehydrohalogenation of an alkyl halide 2.
dehydration of an alcohol 3. dehalogenation of
a vicinal dihalide 4. reduction of an
alkyne reactions 1. addition of hydrogen 8.
hydroboration-oxidation 2. addition of
halogens 9. addition of free radicals 3.
addition of hydrogen halides 10. addition of
carbenes 4. addition of sulfuric acid 11.
epoxidation 5. addition of water 12.
hydroxylation 6. halohydrin formation 13.
allylic halogenation 7. oxymercuration-demercura
tion 14. ozonolysis 15. vigorous
oxidation
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Alkenes, nomenclature C3H6 propylene
CH3CHCH2 C4H8 butylenes CH3CH2CHCH2
a-butylene 1-butene
CH3 CH3CHCHCH3
CH3CCH2 ß-butylene
isobutylene 2-butene 2-methylpropene
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(Z)-3-methyl-2-pentene (3-methyl-cis-2-pentene)

(E)-1-bromo-1-chloropropene

45

• 1. dehydrohalogenation of alkyl halides
• C C KOH(alc.) ? C C
  KX H2O
• H X
• RX 3o gt 2o gt 1o
• no rearragement ?
• may yield mixtures ?
• Saytzeff orientation
• element effect
• isotope effect
• rate k RX KOH
• Mechanism E2

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CH3CHCH3 KOH(alc) ? CH3CHCH2
Br isopropyl bromide propylene CH3CH2CH2CH2-Br
KOH(alc) ? CH3CH2CHCH2
n-butyl bromide 1-butene CH3CH2CHCH3
KOH(alc) ? CH3CH2CHCH2 Br
1-butene 19 sec-butyl bromide
CH3CHCHCH3 2-butene 81
47

• dehydration of alcohols
• C C acid, heat ? C C
  H2O
• H OH
• ROH 3o gt 2o gt 1o
• acid is a catalyst
• rearrangements are possible ?
• mixtures are possible ?
• Saytzeff
• mechanism is E1

48
CH3CH2-OH 95 H2SO4, 170oC ?
CH2CH2 CH3 CH3 CH3CCH3
20 H2SO4, 85-90oC ? CH3CCH2
OH CH3CH2CHCH3 60 H2SO4, 100oC ?
CH3CHCHCH3 OH
CH3CH2CHCH2 CH3CH2CH2CH2-OH H, 140oC ?
CH3CH2CHCH2 rearrangement! ?
CH3CHCHCH3
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• dehalogenation of vicinal dihalides
• 
  
• C C Zn ? C C
  ZnX2
• X X
• eg.
• CH3CH2CHCH2 Zn ? CH3CH2CHCH2
  ZnBr2
• Br Br
• Not generally useful as vicinal dihalides
  are usually made from alkenes. May be used to
  protect a carbon-carbon double bond.

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4. reduction of alkyne
CH3
H
\ / Na or Li C C
anti- NH3(liq)
/ \
H
CH3 trans-2-butene CH3C?CCH3
H H \ /
H2, Pd-C C C syn-
Lindlar catalyst / \

CH3 CH3

cis-2-butene
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• Alkenes, reactions
• 1. Addition of hydrogen (reduction).
• C C H2 Ni, Pt, or Pd ?
  C C
• 
  H H
• a) Requires catalyst.
• 1 synthesis of alkanes
• CH3CHCHCH3 H2, Ni ? CH3CH2CH2CH3
• 2-butene n-butane

52

• 2. Addition of halogens.
• C C X2 ? C C
• 
  X X
• X2 Br2 or Cl2
• test for unsaturation with Br2
• CH3CH2CHCH2 Br2/CCl4 ? CH3CH2CHCH2
• 
  Br Br
• 1-butene 1,2-dibromobutane

53

• Addition of hydrogen halides.
• C C HX ? C C
• 
  H X
• HX HI, HBr, HCl
• Markovnikov orientation
• CH3CHCH2 HI ? CH3CHCH3
• 
  I
• CH3 CH3
• CH2CCH2 HBr ? CH3CCH3
• 
  Br

54

• Addition of sulfuric acid.
• C C H2SO4 ? C C
• 
  H OSO3H
• alkyl hydrogen sulfate
• Markovnikov orientation.
• CH3CHCH2 H2SO4 ? CH3CHCH3
• 
  O
• 
  O-S-O
• 
  OH

55

• Addition of water.
• 
  
• C C H2O, H ? C C
  
• 
  H OH
• a) requires acid
• Markovnikov orientation
• low yield ?
• CH3CH2CHCH2 H2O, H ? CH3CH2CHCH3
• OH

56

• Addition of halogens water (halohydrin
  formation)
• 
  
• C C X2, H2O ? C C HX
• 
  
• 
  OH X
• X2 Br2, Cl2
• Br2 electrophile
• CH3CHCH2 Br2(aq.) ? CH3CHCH2
  HBr
• 
  OH Br

57
7. oxymercuration-demercuration a) Markovnikov
orientation. b) 100 yields. ? c) no
rearrangements ? CH3CH2CHCH2 H2O, Hg(OAc)2
then NaBH4 ? CH3CH2CHCH3

OH
58
With alcohol instead of water alkoxymercuration-
demercuration
C
C ROH, Hg(TFA)2 ? C C


OR HgTFA

C C NaBH4 ?
C C
OR HgTFA
OR H ether
59

• 8. hydroboration-oxidation
• 2 synthesis of alcohols.
• Anti-Markovnikov orientation. ?
• 100 yields. ?
• no rearrangements ?
• CH3CH2CHCH2 (BH3)2 then H2O2, NaOH ?
• CH3CH2CH2CH2-OH
• 
  

60

• 9. Addition of free radicals.
• 
  
• C C HBr, peroxides ? C C
• 
  
• H X
• anti-Markovnikov orientation.
• free radical addition
• CH3CHCH2 HBr, peroxides ? CH3CH2CH2-Br

61
10. Addition of carbenes.

C C CH2CO or CH2N2 ,
h? ? C C
?
CH2 CH2
carbene adds across the
double bond
C C ? ? CH2
62
11. Epoxidation.
C6H5CO3H
C C (peroxybenzoic acid) ?
C C
O

epoxide Free radical addition of
oxygen diradical.
C C ?
? O
63
12. Hydroxylation. (mild oxidation)

C C KMnO4 ? C C
syn

OH OH

OH
C C HCO3H
? C C anti
peroxyformic acid
OH
glycol
64
cis-2-butene KMnO2 ? meso-2,3-dihydroxybuta
ne mp 34o CH3 H
OH H OH
CH3 trans-2-butene KMnO4 ? (S,S)
(R,R)-2,3-dihydroxybutane mp 19o CH3 CH3
H OH HO
H HO H
H OH CH3
CH3 stereoselective and stereospecific
65
13. Allylic halogenation.

C C C X2, heat ? C
C C HX
H
? allyl
X CH2CHCH3 Br2, 350oC ? CH2CHCH2Br
HBr a) X2 Cl2 or Br2 b) or
N-bromosuccinimide (NBS)
66
14. Ozonolysis.

C C O3 then Zn, H2O ?
C O O C used for identification of
alkenes CH3 CH3CH2CHCCH3
O3 then Zn, H2O ?

CH3
CH3CH2CHO OCCH3
67
15. Vigorous oxidation. CH2 KMnO4, heat
? CO2 CHR KMnO4, heat ? RCOOH
carboxylic acid CR2 KMnO4, heat ?
OCR2 ketone
68
CH3CH2CH2CHCH2 KMnO4, heat ?
CH3CH2CH2COOH
CO2 CH3
CH3 CH3CCHCH3 KMnO4, heat
? CH3CO HOOCCH3
69
Dienes nomenclature syntheses same as
alkenes reactions same as alkenes special
conjugated dienes 1. more stable 2.
preferred products of eliminations 3. give
1,2- 1,4- addition products
70

• (cumulated dienes are not very stable and are
  rare)
• isolated dienes are as you would predict, undergo
  addition reactions with one or two moles
• ? conjugated dienes are unusual in that they
• are more stable than predicted
• are the preferred products of eliminations
• give 1,2- plus 1,4-addition products

71
nomenclature CH2CHCHCH2 CH3CHCHCH2CHCHCH3
1,3-butadiene 2,5-heptadiene
conjugated isolated 2-methyl-1,
3-butadiene (isoprene) conjugated
72
isolated dienes (as expected)
1,5-hexadiene CH2CHCH2CH2CHCH2 H2, Ni
? CH3CH2CH2CH2CHCH2 CH2CHCH2CH2CHCH2
2 H2, Ni ? CH3CH2CH2CH2CH2CH3 CH2CHCH2CH2C
HCH2 Br2 ? CH2CHCH2CH2CHCH2

Br Br CH2CHCH2CH2CHCH2 HBr ?
CH3CHCH2CH2CHCH2

Br CH2CHCH2CH2CHCH2 2 HBr ?
CH3CHCH2CH2CHCH3
Br
Br
73
conjugated dienes yield 1,2- plus
1,4-addition CH2CHCHCH2 H2, Ni ?
CH3CH2CHCH2 CH3CHCHCH3 CH2CHCHCH2
2 H2, Ni ? CH3CH2CH2CH3 CH2CHCHCH2
Br2 ? CH2CHCHCH2 CH2CHCHCH2
Br Br
Br
Br CH2CHCHCH2 HBr ? CH3CHCHCH2
CH3CHCHCH2
Br
Br

peroxides CH2CHCHCH2 HBr ?
CH2CHCHCH3 CH2CH2CHCH2
Br
Br
74
Alkynes nomenclature syntheses 1.
dehydrohalogenation of vicinal dihalides 2.
coupling of metal acetylides with alkyl
halides reactions 1. reduction 2. addition
of halogens 3. addition of hydrogen
halides 4. addition of water 5. as
acids 6. with Ag 7. oxidation
75
Alkynes, nomenclature HC?CH ethyne acetylene

CH3 CH3CH2C?CH HC?CCHCH2CH3 1-butyne
3-methyl-1-pentyne ethylacetylene sec-butylace
tylene
76

• Synthesis, alkynes
• dehydrohalogenation of vicinal dihalides
• H H H
• 
  
• C C KOH ? C C KX
  H2O
• 
  
• X X
  X
• H
• C C NaNH2 ? C ? C NaX
  NH3
• X

77
(No Transcript)
78

• coupling of metal acetylides with 1o/CH3 alkyl
  halides
• R-C?C-Na RX ? R-C?C-R NaX
• SN2
• RX must be 1o or CH3X
• CH3C?C-Li CH3CH2-Br ? CH3C?CCH2CH3

79
Alkyne, reactions 1. Addition of hydrogen
(reduction)
HC?CH 2 H2, Pt ? CH3CH3 HC?CH one
mole H2, Pt ? CH3CH3 CH2CH2 HC?CH

H
\ / Na or Li C
C anti-
NH3(liq) / \

H C ? C \ / H2, Pd-C
C C syn-
Lindlar catalyst / \
H
H
80
CH3
H
\ / Na or Li C C
anti- NH3(liq)
/ \
H
CH3 trans-2-butene CH3C?CCH3
H H \ /
H2, Pd-C C C syn-
Lindlar catalyst / \

CH3 CH3

cis-2-butene
81

• Addition of X2
• X
  X X
• 
  
• C?? C X2 ? C C X2 ? C
  C
• 
  
• 
  X X X
• 
  Br Br Br
• CH3C?CH Br2 ? CH3CCH Br2 ?
  CH3-C-CH
• 
  Br Br Br

82

• Addition of hydrogen halides
• H
  H X
• 
  
• C?? C HX ? C C HX ? C
  C
• 
  
• 
  X H X
• HX HI, HBr, HCl
• Markovnikov orientation
• 
  Cl
• CH3C?CH HCl ? CH3CCH2 HCl ?
  CH3CCH3
• 
  Cl Cl

83

• Addition of water. Hydration.
• 
  O
  
• C ? C H2O, H, HgO ? CH2 C
• H OH
• C C
  
• enol keto-enol tautomerism
• Markovnikov orientation.

84
CH3CH2C?CH H2O, H2SO4, HgO ? 1-butyne


O
CH3CH2CCH3

2-butanone
85

• As acids. terminal alkynes only!
• with active metals
• CH3C?CH Na ? CH3C?C-Na ½ H2 ?
• with bases CH4 lt NH3 lt HC?CH lt ROH lt H2O lt
  HF
• CH3C?CH CH3MgBr ? CH4 CH3C
  ?CMgBr
• SA SB
  WA WB

86

• Ag terminal alkynes only!
• CH3CH2C?CH AgNO3 ? CH3CH2C?C-Ag
  ?
• CH3C?CCH3 AgNO3 ? NR (not
  terminal)
• formation of a precipitate is a test for terminal
  alkynes.

87
7. Oxidation
CH3CH2C?CCH3 KMnO4 ? CH3C?CH
hot KMnO4 ? CH3C?CCH3 O3 then Zn, H2O
?
CH3CH2COOH
HOOCCH3
CH3COOH CO2
2 CH3COOH
88
Alicyclics nomenclature syntheses like
alkanes, alkenes, alcohols, etc. reactions as
expected exceptions cyclopropane/cyclobutane
89
methylcyclopentane 1,1-dimethylcyclobutane
trans-1,2-dibromocyclohexane
90
3
4
2
5
1
6
cyclopentene 3-methylcyclohexene 1,3-cyclobu
tadiene
91
Cycloalkanes, syntheses A. Modification of a
cyclic compound
H2, Ni
Sn, HCl
Mg then H2O
92

• Cycloalkanes, reactions
• halogenation
• 2. combustion
• 3. cracking
• 4. exceptions

Cl2, heat
HCl
93
exceptions H2, Ni,
80o CH3CH2CH3 Cl2, FeCl3 Cl-CH2CH2CH
2-Cl H2O, H CH3CH2CH2-OH conc.
H2SO4 CH3CH2CH2-OSO3H HI
CH3CH2CH2-I
94
exceptions (cont.) H2, Ni, 200o ?
CH3CH2CH2CH3
95
Cycloalkenes, syntheses
KOH(alc)
H, ?
cyclohexene
Zn
96

• Cycloalkenes, reactions
• addition of H2 8. hydroboration-oxid.
• addition of X2 9. addition of free radicals
• addition of HX 10. addition of carbenes
• addition of H2SO4 11. epoxidation
• addition of H2O,H 12. hydroxylation
• addition of X2 H2O 13. allylic halogenation
• oxymerc-demerc. 14. ozonolysis
• 15. vigorous oxidation

97
H2, Pt
Br2, CCl4
trans-1,2-dibromocyclohexane
HBr
H2SO4
Markovnikov
H2O, H
Br2 (aq.)
dimerization
98
HF
H2O,Hg(OAc)2
NaBH4
Markovnikov
(BH3)2 H2O2, NaOH
anti-Markovnikov
HBr, perox.
anti-Markovinikov
polymer.
CH2CO,hv
PBA
99
KMnO4
cis-1,2-cylohexanediol
HCO3H
trans-1,2-cyclohexanediol
Br2, heat
O3 Zn, H2O
OCHCH2CH2CH2CH2CHO
KMnO4, heat
HO2CCH2CH2CH2CH2CO2H
100
Epoxides nomenclature syntheses 1.
epoxidation of alkenes reactions 1. addition
of acids 2. addition of bases
101
Epoxides, nomenclature
ethylene oxide propylene oxide
cyclopentene oxide (oxirane)
(methyloxirane)
Synthesis
C6H5CO3H
ß-butylene oxide
cis-2-butene
102

• epoxides, reactions
• acid catalyzed addition

OH CH2CH2 OH
H2O, H

OH CH3CH2-O-CH2CH2
CH3CH2OH, H
OH CH2CH2 Br
HBr
103
2. Base catalyzed addition
OH CH2CH2 OH
CH3CH2-O-CH2CH2-OH
H2N-CH2CH2-OH
CH3CH2CH2CH2-OH
104
Mechanisms Free radical substitution SN2 SN1
E2 E1 ionic electrophilic addition free
radical electrophilic addition Memorize (all
steps, curved arrow formalism, RDS) and know
which reactions go by these mechanisms!
105

• Free Radical Substitution Mechanism
• initiating step
• XX ? 2 X
• propagating steps
• 2) X RH ? HX R
• R XX ? RX X
• 2), 3), 2), 3)
• terminating steps
• 4) 2 X ? XX
• 5) R X ? RX
• 6) 2 R ? RR

106
Substitution, nucleophilic, bimolecular
(SN2) CH3 gt 1o gt 2o gt 3o
107

• Substitution, nucleophilic, unimolecular (SN1)
• 3o gt 2o gt 1o gt CH3

1) 2)
108
Mechanism elimination, bimolecular E2 3o
gt 2o gt 1o
109
Elimination, unimolecular E1 3o gt 2o gt
1o
110
(No Transcript)
111

• Free radical electrophilic addition of HBr
• Initiating steps
• 1) peroxide ? 2 radical
• 2) radical HBr ? radicalH Br
  (Br electrophile)
• Propagating steps
• 3) Br CH3CHCH2 ? CH3CHCH2-Br (2o free
  radical)
• 
  
• 4) CH3CHCH2-Br HBr ? CH3CH2CH2-Br
  Br
• 3), 4), 3), 4)
• Terminating steps
• Br Br ? Br2
• Etc.