1. CHE-300 Review
nomenclature
syntheses
reactions
mechanisms

2. Alkanes
Alkyl halides
Alcohols
Ethers
Alkenes
conjugated 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
CH3CH2CH2CH2CH2CH CH3CHCH2CH2CH3
(n-hexane) (isohexane)
n-hexane 2-methylpentane
CH CH3
CH3CH2CHCH2CH3 CH3CCH2CH3
(no common name) CH3
3-methylpentane (neohexane)
2,2-dimethylbutane
CH3CHCHCH3
(no common name)
2,3-dimethylbutane

5. Alkanes, syntheses
1. Addition of hydrogen (reduction).
| | | |
— C = C — H Ni, Pt, or Pd  — C — C —
| |
H H
Requires catalyst.
CH3CH=CHCH H2, Ni  CH3CH2CH2CH3
2-butene n-butane

6. Reduction of an alkyl halide
a) hydrolysis of a Grignard reagent (two steps)
i) R—X 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  CH3CH2CH Mg(OH)Br
propane

7. with an active metal and an acid R—X + metal/acid  RH
active metals = Sn, Zn, Fe, etc.
acid = HCl, etc. (H+)
CH3CH2CHCH Sn/HCl  CH3CH2CH2CH SnCl2 Cl
sec-butyl chloride n-butane
CH CH3
CH3CCH Zn/H+  CH3CHCH 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
CH CH3
(CH3CH)2-CuLi CH3CH2CH2-Br  CH3CH-CH2CH2CH3
2-methylpentane
(isohexane)
mechanism = SN2
Note: the R´X should be a 1o or methyl halide for the best yields of the final product.

9. Alkanes, reactions
1. Halogenation
R-H X2, heat or hv  R-X HX
a) heat or light required for reaction.
b) X2: Cl2 > Br2  I2
c) yields mixtures 
d) H: 3o > 2o > 1o > CH4
e) bromine is more selective
f) free radical substitution

10. CH3CH2CH2CH3 + Br2, hv  CH3CH2CH2CH2-Br 2% + CH3CH2CHCH3 98% Br
n-butane n-butyl bromide +
CH3CH2CHCH % Br
sec-butyl bromide
CH CH3
CH3CHCH Br2, hv  CH3CHCH2-Br <1%
isobutane isobutyl bromide
CH3
CH3CCH %
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
CH CH3
CH3CHCH2CHCH3 CH3CCH3
Br I
2-bromo-4-methylpentane tert-butyl iodide
2-iodo-2-methylpropane
2o o
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 > 2o > CH3 > 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 bromobutane
CH CH3
CH3CCH 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. CH3CHCH2-OH + PBr3  CH3CHCH2-Br
…from alcohols: b) PX3
i) PX3 = PCl3, PBr3, P + I2
ii) ROH: CH3 > 1o > 2o
iii) no rearragements
CH3CH2-OH P, I2  CH3CH2-I
ethyl alcohol ethyl iodide
ethanol iodoethane
CH CH3
CH3CHCH2-OH PBr3  CH3CHCH2-Br
isobutyl alcohol isobutyl bromide
2-methyl-1-propanol bromo-2-methylpropane

16. Halogenation of certain hydrocarbons. R-H + X2, Δ or hν  R-X + HX
(requires Δ or hν; Cl2 > Br2 (I2 NR); 3o>2o>1o)
yields mixtures!  In syntheses, limited to those hydrocarbons that yield only one monohalogenated product.
CH CH3
CH3CCH Cl2, heat  CH3CCH2-Cl
CH CH3
neopentane neopentyl chloride
2,2-dimethylpropane chloro-2,2-dimethylpropane

17. 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 idodopropane
iii) SN R-X should be 1o or CH3

18. 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

19. 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 :NH  R-NH 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

20. 2. dehydrohalogenation of alkyl halides
| | | |
— C — C — KOH(alc.)  — C = C — KX H2O
| |
H X
RX: 3o > 2o > 1o
no rearragement 
may yield mixtures 
Saytzeff orientation
element effect
isotope effect
rate = k [RX] [KOH]
Mechanism = E2

21. CH3CHCH3 + KOH(alc)  CH3CH=CH2 Br
isopropyl bromide propylene
CH3CH2CH2CH2-Br KOH(alc)  CH3CH2CH=CH2
n-butyl bromide butene
CH3CH2CHCH KOH(alc)  CH3CH2CH=CH2
Br butene 19%
sec-butyl bromide +
CH3CH=CHCH3
2-butene 81%

22. 3. preparation of Grignard reagent CH3CH2CH2-Br + Mg  CH3CH2CH2-MgBr
n-propyl bromide n-propyl magnesium bromide
reduction
CH3CH2CH2-MgBr H2O  CH3CH2CH Mg(OH)Br
propane
CH3CH2CHCH Sn/HCl  CH3CH2CH2CH SnCl2 Cl
sec-butyl chloride n-butane

23. 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

24. Alcohols, nomenclature
CH CH3
CH3CHCH2CHCH3 CH3CCH3
OH OH
4-methyl-2-pentanol tert-butyl alcohol
2-methyl-2-propanol
2o o
CH3
HO-CHCH2CH3 CH3CH2CH2-OH
sec-butyl alcohol n-propyl alcohol
2-butanol propanol
2o o

25. Alcohols, syntheses
1. oxymercuration-demercuration:
Markovnikov orientation.
100% yields. 
no rearrangements 
CH3CH2CH=CH2 + H2O, Hg(OAc)2; then NaBH4 
CH3CH2CHCH3 OH

26. 2. hydroboration-oxidation:
Anti-Markovnikov orientation. 
100% yields. 
no rearrangements 
CH3CH2CH=CH2 + (BH3)2; then H2O2, NaOH 
CH3CH2CH2CH2-OH

27. Reaction of alcohols
1. with HX:
R-OH HX  R-X H2O
a) HX: HI > HBr > HCl
b) ROH: 3o > 2o > CH3 > 1o SN1/SN2
c) May be acid catalyzed
d) Rearrangements are possible except with most 1o alcohols.

28. CH3CH2CH2CH2-OH + NaBr, H2SO4, heat  CH3CH2CH2CH2-Br
n-butyl alcohol (HBr) n-butyl bromide
1-butanol bromobutane
CH CH3
CH3CCH 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

29.  With PX3 ROH + PX3  RX PX3 = PCl3, PBr3, P + I2 No rearrangements
ROH: CH3 > 1o > 2o
CH CH3
CH3CCH2-OH PBr3  CH3CCH2-Br
neopentyl alcohol ,2-dimethyl-1-bromopropane 

30. Dehydration of alcohols
| | | |
— C — C — acid, heat  — C = C — H2O
| |
H OH
ROH: 3o > 2o > 1o
acid is a catalyst
rearrangements are possible 
mixtures are possible 
Saytzeff
mechanism is E1

31. CH3CH2-OH + 95% H2SO4, 170oC  CH2=CH2
CH3CCH % H2SO4, 85-90oC  CH3C=CH2 OH
CH3CH2CHCH % H2SO4, 100oC  CH3CH=CHCH3
+ CH3CH2CH=CH2
CH3CH2CH2CH2-OH H+, 140oC  CH3CH2CH=CH2
rearrangement!  CH3CH=CHCH3

32. As acids.
With active metals:
ROH Na  RONa ½ H2 
CH3CH2-OH K  CH3CH2-O-K H2
With bases:
CH4 < NH3 < ROH < H2O < HF
ROH NaOH  NR!
CH3CH2OH CH3MgBr  CH Mg(Oet)Br

33. Ester formation. CH3CH2-OH + CH3CO2H, H+  CH3CO2CH2CH3 + H2O
CH3CH2-OH CH3COCl  CH3CO2CH2CH HCl
CH3-OH CH3SO2Cl  CH3SO3CH HCl
Esters are alkyl “salts” of acids.

34. Oxidation
Oxidizing agents: KMnO4, K2Cr2O7, CrO3, NaOCl, etc.
Primary alcohols:
CH3CH2CH2-OH KMnO4, etc.  CH3CH2CO2H
carboxylic acid
Secondary alcohols:
OH O
CH3CH2CHCH K2Cr2O7, etc.  CH3CH2CCH3
ketone
Teriary alcohols:
no reaction.

35. Primary alcohols ONLY can be oxidized to aldehydes:
CH3CH2CH2-OH C5H5NHCrO3Cl  CH3CH2CHO
pyridinium chlorochromate aldehyde or
CH3CH2CH2-OH K2Cr2O7, special conditions 

36. Ethers
nomenclature
syntheses
1. Williamson Synthesis
2. alkoxymercuration-demercuration
reactions
1. acid cleavage

37. 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 CH3CH-O-CHCH3
diethyl ether diisopropyl ether

38. 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
CH3CH2CH2-OH + HBr  CH3CH2CH2-Br isopropyl n-propyl ether
note: the alkyl halide is primary! 

39. 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! 

40. 2. alkoxymercuration-demercuration: Markovnikov orientation.
100% yields. 
no rearrangements 
CH3CH=CH2 + CH3CHCH3, Hg(TFA)2; then NaBH4  OH
CH3 CH3
CH3CH-O-CHCH3
diisopropyl ether
Avoids the elimination with 2o/3o RX in Williamson Synthesis.

41. Reactions, ethers:
Acid cleavage.
R-O-R´ (conc) HX, heat  R-X R´-X
CH3CH2-O-CH2CH HBr, heat  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 addition of carbenes
4. addition of sulfuric acid epoxidation
5. addition of water hydroxylation
6. halohydrin formation allylic halogenation
7. oxymercuration-demercuration ozonolysis
15. vigorous oxidation

43. Alkenes, nomenclature
C3H6 propylene CH3CH=CH2
C4H8 butylenes CH3CH2CH=CH2
α-butylene
1-butene
CH3
CH3CH=CHCH CH3C=CH2
β-butylene isobutylene
2-butene 2-methylpropene

44. * * * * (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 > 2o > 1o
no rearragement 
may yield mixtures 
Saytzeff orientation
element effect
isotope effect
rate = k [RX] [KOH]
Mechanism = E2

46. CH3CHCH3 + KOH(alc)  CH3CH=CH2 Br
isopropyl bromide propylene
CH3CH2CH2CH2-Br KOH(alc)  CH3CH2CH=CH2
n-butyl bromide butene
CH3CH2CHCH KOH(alc)  CH3CH2CH=CH2
Br butene 19%
sec-butyl bromide +
CH3CH=CHCH3
2-butene 81%

47. dehydration of alcohols:
| | | |
— C — C — acid, heat  — C = C — H2O
| |
H OH
ROH: 3o > 2o > 1o
acid is a catalyst
rearrangements are possible 
mixtures are possible 
Saytzeff
mechanism is E1

48. CH3CH2-OH + 95% H2SO4, 170oC  CH2=CH2
CH3CCH % H2SO4, 85-90oC  CH3C=CH2 OH
CH3CH2CHCH % H2SO4, 100oC  CH3CH=CHCH3
+ CH3CH2CH=CH2
CH3CH2CH2CH2-OH H+, 140oC  CH3CH2CH=CH2
rearrangement!  CH3CH=CHCH3

49. dehalogenation of vicinal dihalides
| | | |
— C — C — Zn  — C = C — ZnX2
| |
X X
eg.
CH3CH2CHCH Zn  CH3CH2CH=CH ZnBr2
Br Br
Not generally useful as vicinal dihalides are usually made from alkenes. May be used to “protect” a carbon-carbon double bond.

50. 4. reduction of alkyne CH3 H \ / Na or Li C = C anti- NH3(liq) / \
\ /
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

51. Alkenes, reactions
1. Addition of hydrogen (reduction).
| | | |
— C = C — H Ni, Pt, or Pd  — C — C —
| |
H H
a) Requires catalyst.
#1 synthesis of alkanes
CH3CH=CHCH H2, Ni  CH3CH2CH2CH3
2-butene n-butane

52. 2. Addition of halogens.
| | | |
— C = C — X  — C — C —
| |
X X
X2 = Br2 or Cl2
test for unsaturation with Br2
CH3CH2CH=CH Br2/CCl4  CH3CH2CHCH2
Br Br
1-butene ,2-dibromobutane

53. Addition of hydrogen halides.
| | | |
— C = C — HX  — C — C —
| |
H X
HX = HI, HBr, HCl
Markovnikov orientation
CH3CH=CH HI  CH3CHCH3 I
CH3 CH3
CH2C=CH HBr  CH3CCH3 Br

54. Addition of sulfuric acid.
| | | |
— C = C — H2SO  — C — C —
| |
H OSO3H
alkyl hydrogen sulfate
Markovnikov orientation.
CH3CH=CH 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 
CH3CH2CH=CH 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
CH3CH=CH Br2(aq.)  CH3CHCH HBr
OH Br

57. 7. oxymercuration-demercuration:
a) Markovnikov orientation.
b) 100% yields. 
c) no rearrangements 
CH3CH2CH=CH2 + 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 
CH3CH2CH=CH2 + (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
CH3CH=CH HBr, peroxides  CH3CH2CH2-Br

61. 10. Addition of carbenes.
| | | |
— C = C — + CH2CO or CH2N2 , hν  — 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 | |
glycol

64. stereoselective and stereospecific
cis-2-butene + KMnO2  meso-2,3-dihydroxybutane mp 34o
CH3
H OH
trans-2-butene + KMnO4  (S,S) & (R,R)-2,3-dihydroxybutane mp 19o
CH3 CH3
H OH HO H
HO H H OH
CH CH3
stereoselective and stereospecific

65. 13. Allylic halogenation.
| | | | | |
— C = C — C — + X2, heat  — C = C — C — + HX
| |
H  allyl X
CH2=CHCH Br2, 350oC  CH2=CHCH2Br + 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
CH3CH2CH=CCH O3; then Zn, H2O 
CH3CH2CH=O O=CCH3

67. 15. Vigorous oxidation.
=CH KMnO4, heat  CO2
=CHR KMnO4, heat  RCOOH carboxylic acid
=CR KMnO4, heat  O=CR ketone

68. CH3CH2CH2CH=CH2 + KMnO4, heat 
CH3CH2CH2COOH + CO2
CH CH3
CH3C=CHCH3 + KMnO4, heat  CH3C=O + HOOCCH3

69. Dienes
nomenclature
syntheses
same as alkenes
reactions
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:
CH2=CHCH=CH2 CH3CH=CHCH2CH=CHCH3
1,3-butadiene ,5-heptadiene
conjugated isolated
2-methyl-1,3-butadiene (isoprene)
conjugated

72. isolated dienes: (as expected) 1,5-hexadiene
CH2=CHCH2CH2CH=CH H2, Ni  CH3CH2CH2CH2CH=CH2
CH2=CHCH2CH2CH=CH H2, Ni  CH3CH2CH2CH2CH2CH3
CH2=CHCH2CH2CH=CH Br2  CH2CHCH2CH2CH=CH2
Br Br
CH2=CHCH2CH2CH=CH HBr  CH3CHCH2CH2CH=CH2 Br
CH2=CHCH2CH2CH=CH HBr  CH3CHCH2CH2CHCH3
Br Br

73. conjugated dienes yield 1,2- plus 1,4-addition:
CH2=CHCH=CH H2, Ni  CH3CH2CH=CH2 + CH3CH=CHCH3
CH2=CHCH=CH H2, Ni  CH3CH2CH2CH3
CH2=CHCH=CH Br2  CH2CHCH=CH2 + CH2CH=CHCH2
Br Br Br Br
CH2=CHCH=CH HBr  CH3CHCH=CH2 + CH3CH=CHCH2
Br Br
peroxides
CH2=CHCH=CH HBr  CH2CH=CHCH CH2CH2CH=CH2
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 methyl-1-pentyne
ethylacetylene sec-butylacetylene

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

78. coupling of metal acetylides with 1o/CH3 alkyl halides
R-CC-Na R´X  R-CC-R´ + NaX
SN2
R´X must be 1o or CH3X
CH3CC-Li CH3CH2-Br  CH3CCCH2CH3

79. 1. Addition of hydrogen (reduction)
Alkyne, reactions
1. Addition of hydrogen (reduction)
HCCH H2, Pt  CH3CH3
[ HCCH + one mole H2, Pt  CH3CH CH2=CH2 + HCCH ] H
\ /
Na or Li C = C anti-
NH3(liq) / \
— 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  CH3C=CH 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  CH3C=CH HCl  CH3CCH3
Cl Cl

83. Addition of water. Hydration.
— 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 < NH3 < HCCH < ROH < H2O < HF
CH3CCH CH3MgBr  CH CH3C CMgBr
SA SB WA WB

86. Ag+ terminal alkynes only!
CH3CH2CCH AgNO3  CH3CH2CC-Ag+ 
CH3CCCH AgNO3  NR (not terminal)
formation of a precipitate is a test for terminal alkynes.

87. 7. Oxidation
CH3CH2CCCH KMnO4 
CH3CCH hot KMnO4 
CH3CCCH 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. cyclopentene 3-methylcyclohexene 1,3-cyclobutadiene4 2 5 1 6
cyclopentene methylcyclohexene 1,3-cyclobutadiene

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 CH3CH2CH2-I CH3CH2CH3 Cl2, FeCl3
Cl-CH2CH2CH2-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+, Δ
cyclohexene Zn

96. Cycloalkenes, reactions:
addition of H hydroboration-oxid.
addition of X 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 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. trans-1,2-cyclohexanediol
KMnO4
cis-1,2-cylohexanediol
HCO3H
trans-1,2-cyclohexanediol
Br2, heat
O Zn, H2O
O=CHCH2CH2CH2CH2CH=O
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
cis-2-butene
β-butylene oxide

102. acid catalyzed addition
epoxides, reactions:
acid catalyzed addition OH
CH2CH2
H2O, H+ OH
CH3CH2-O-CH2CH2
CH3CH2OH, H+ OH
CH2CH2 Br
HBr

103. 2. Base catalyzed additionOH
CH2CH2
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:
X—X  2 X•
propagating steps:
2) X• R—H  H—X R•
R• X—X  R—X X•
2), 3), 2), 3)…
terminating steps:
4) 2 X•  X—X
5) R• + X•  R—X
6) 2 R•  R—R

106. Substitution, nucleophilic, bimolecular (SN2)
CH3 > 1o > 2o > 3o

107. Substitution, nucleophilic, unimolecular (SN1)
3o > 2o > 1o > CH3 1) 2)

108. Mechanism = elimination, bimolecular E2
3o > 2o > 1o

109. Elimination, unimolecular E1
3o > 2o > 1o

111. Free radical electrophilic addition of HBr:
Initiating steps:
1) peroxide  2 radical•
2) radical• + HBr  radical:H + Br• (Br• electrophile)
Propagating steps:
3) Br• + CH3CH=CH2  CH3CHCH2-Br (2o free radical) •
4) CH3CHCH2-Br HBr  CH3CH2CH2-Br Br•
3), 4), 3), 4)…
Terminating steps:
Br• + Br•  Br2
Etc.