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1. ???????,??????????????,????

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Title: 1. ???????,??????????????,????


1
??? ???
??????????????
2

3
??? ?????????
  • ????

4
????????????
5
????
  • 1. ???????,??????????????,?????????????????????,
    ?????????
  • 2.???????????????,???????

6
(No Transcript)
7
??? ???
  • ??????
  • 1. ???
  • 2.????????,????????
  • 3.???????
  • 4.????????????????,?????1

R-F R-Cl R-Br R-I
1.82 1.94 1.79 1.64
8
??????
??(nm) 0.139 0.176 0.194 0.214
??(kJ/mol) 456 351 293 243
C-X????? ????????????????????
9
1.??????
  • ?????????????,??????????,?Nu-?????OH-?NH3??

10
????
????
?????????
????
??
??
????
  • ????

????
??
????
??
(a)?????,????????????
11
(b) ?????????
(c) ???????,??????????
(d) ???????,?????????
12

???
???

?????
????????
????????
13
?
14
????
??? ?? ?? ??

15
???(??????)???

????gt?????gt?????gt?????gt????
16
???(?????)???
RI RBr RCl RF
  • ???
  • ????

??????
17
???? ????????????????
????????
??????
ß-??
???????????????? ???,????????
???????????????, ????
a-??
1,1-??
18
1,3-??
??????????????,??????? ???
19
Saytzeff Rule ????? ??????????????????
20
????????
21
3. ?????
R???3???
  • 1). ??????
  • Wurtz???

22
Corey-House???
23
?1
24
?2

25
2).Grignard?????

26
?????????,???Grignard??,?????,?????
27
??????????,?????
28
Grignard?????????
29
Grignard??????????????????,?????????????
????????????
RLi?RNagtRMgXgtRZnXgtR2Cd
30
4. ??

(1)????H2,Ni?Pd?Pt (2)????LiAlH4?NaBH4?
Zn/HCl
31
LiAlH4?NaBH4???
LiAlH4 NaBH4

?? ? ??
??? ? ?
???? COOH ? CHO? CHO COOR?
RCOR RCOR -NO2?-CN
???? ?????? ???
32
??? ????????
  • ?. ???? (Reaction Mechanism)
  • 1). SN1??
  • 2). SN2??
  • 3). ?????
  • ?. ????
  • 1). SN2??
  • 2). SN1??

33

?. ????????? 1). ??????? 2). ???? (L) 3). ????
(Nu) 4). ?? ?. ?????? ?. ????????

34
?. ????
1). ??????? (Substitution Nucleophilic
Unimolecular) ( SN 1)????
??? ???????
???????
??? ??????????
?????? ????????
35
?
36
????-???
37
?? ??????????????
?SN 1 ??????? ????????? ?????????? ??????????
2). ??????? (Substitution Nucleophilic
Bimolecular) ( SN 2)????
???????????????????? ???????????????
????
38
??????
T
????
??
-????????
????
??
?????
????????????????
?????????????????,???? ??????,????????????????
???????,?????????????? T.
39
S N 2 ????
40
?
41
?????,??????????????????????
p??????????????????? p?????????
? SN 2 ?????????
????????????? ?????
3). ?????
??SN1 ? SN2 ?????,?? ?SN1???????
?????????????????,???? ????
42
????
(a) ???????????????,????? ?????
(b) ????????,??????????
(c) ???????????
???????????????,?????? ????
43
3. ???????
  • ????

??????????????
SN2??
???????????????????,?? ????????-Walden???
L-
Nu
44
(R) - (-) - 2 - ?? a25D -34.25 ??????100
(S) - (-) - 2 - ?? a25D -9.90 ??????100
a 23.5
45
SN1??
  • ????

?????????????????,???? ??????
???????,???????
???? (Racemization)
46
???,SN1??????????????
?C???????,??L ?????, Nu? L
??????????????,?? ????? ?
???
47
?. ?????????
  • ????????????????
  • ?????
  • ????????????
  • ???????
  • ????

(1)???????
???????????
SN 2??
?? gt ? gt ? gt ?
?????????
48
???????????SN 2??
?????,?? ???????4? ???????? ?????5??? ???,????? ??
??
???????????????, Nu??????????
49
SN1??
A. ????
??????????????,???SN 1 ?????????
???? (k1)
0.26 0.69 0.86 100 10 5 10 10
??????I? ??????C??, SN 1??????, ?? ?????
50
???????????????(R-ZCH2-L), SN 1????????
109 1.0
0.2
SN 1?? ??
?????????????,???? ????,??????????
?SN 2????,???????? ?????SN1??????
B. ????
????, ????? ????, ????? ????? ??
RBr???????????
RBr ???50? MeBr
1.00 EtBr 1.00 i-pBr
11.6 t-BuBr 1.2106
???
?????
51
???????
  • ??????????SN1,????SN2
  • ??SN1???,?????????,??p-?????,????????,?????????

52
??SN2?????,???????,???????????,????????,?????SN2?

53
????????SN1,????SN2?
  • SN2?????????????????,???????,??????

54
??SN1?????,???????????,???????????????,???????????

55
(2)???????
Nu
Nu? SN2?????????
??
1???????????????????? -OH gt H2O, CH3O- gt
CH3OH
2)???????,??????,????? ?????,?????????????
, ??????
A. ???????????,??????????
?????????????????????????????????????
RO- gt HO- gtgt RCO2- gt ROH gt H2O
CH3O- gt PhO- gt CH3CO2- gt NO2-
56
????????????,???????? ?????????
B. ??????,?????,????????, ??????,?????
H2N- gt OH- gt F-
C. ??????????????,??????? ??,????????
57
F- lt Cl- lt Br- lt I-
R - O - lt R - S - lt R - Se -
D. ?????????????????,???? ???????????,???????
?,? ??????????????
????,???????,????? ?????????,????????
???????
??
???????,???????
58
(3)???? (Leaving groups)
?????????? ???????,?? ????
??????????,???????????
a) ??????????????
??????? ??
??? 1
??? 2
??? 1
??? 2
???????? pKa lt 5??????,? I- ??? HI?????
59
TsOH
MsO-
CF3SO3- ?????????
b) ???????????,?????????
F Cl Br I
?? ?? ?? ??
??????????
60
Question
  • ????I-????????,?????????

61
(4)????
????????? ?????????, ???????? ???
?????
???? e??, ????????
?????CCl4,, CS2,
µ- ???
(µ 0)
???EtOH, H2O, CH3COOH
????????? ???????
????
????THF, Et2O, DMF, DMSO,
HMPT
(µ? 0)
??????
?????
??????
???????????
?? ?????????,????????
62
SN 1??
??????????? ???????,???? ???,???????, ????????
SN 2??
????????????,????????, ???????,????????,???
??? ???
????????? ?????????, ?????????? ?,????????
????????????? ?????SH- gt CN- gt I- gt OH- gt N3- gt
Br- gt CH3CO2- gt Cl - gt F- gt H2O
63
SN 2????????????????
???????? (Polar Aprotic Solvents) ???
Nu????,??????????, ?????????????,?????? ????
????????????
64
??????????,X - ????????
F - gt Cl - gt Br - gt I -
???????????????
?????????????SN 2?????
?? k2
DMF 3
103 CH3OH 3
10-2
????????????????,?DMF?? CH3OH? ????
65
????????
  • ????????(?????)??????????????????,????????
  • ???????1)??????2)???????????
  • ??????-CO2-?-O-?-OH?
  • -OR?NR2?-X?etc.

66
???????(SN2)
67
(S)-2-?????NaOH????,??????????(SN2).

68
(R)-2-?????NaOH???Ag2O?????????(R)-2-?????,???????
????????(??SN2)?
69
Wenstein?Lucas????-3-?-2-????HBr??,??????2,3-????
???-3-?-2-????HBr??,??????2,3-?????
70
??

71
??????????
  • ??????

72
??SN1?SN2????????????

73
1???????????
74
1???????????
75
1???????????
  • ????????????????,???????????????
  • ??????

76
1???????????
77
1???????????
  • ????????????
  • SO2Cl??????,?????????????,??????????????

Cl
H
Cl
H
Et2O
78
1???????????
  • Alkyl Halides from Alcohol by Treatment with
    Phosphorus Trihalides

79
1???????????
  • ---- A simple SN2 reaction of three equivalents
    of the alcohol with the reagent leads to the
    formation of a phosphite ester with three
    phosphorus-oxygen bonds.
  • The high strength of the phosphorus-oxygen bond
    provides the driving force for this step.
  • Bromide ion then effects SN2 displacement

80
1???????????
  • ??????????????

81
2?Williamson ???
  • How to synthesize the following ether

82
2?Williamson ???
  • The answer is ---- path a is correct
  • Why?

83
2?Williamson ???

84
2?Williamson ???
  • Sulfonate esters can be used in the Williamson
    ether synthesis

85
3?????????
  • ?????????????????

86
3?????????
  • This reaction illustrateds a problem common to
    many organic reactions a product is often
    capable of entering into reaction with one or
    more of the starting materials.

87
3?????????
  • The ability to obtain B in high yield depends on
    the relative rates k1 and k2
  • When k1 gt k2, B can be obtained in good yield
    through control of the reaction time
  • When k1 lt k2, the yield of B is low
  • In the above reaction, the rate of reaction of RX
    with - SH will be higher than that with - SR by
    using an excess of NaSH

88
3?????????
  • An alternative method for the formation of thiol
    is the reaction of the anion of thiolacetic acid
    with alkyl halides to form thiol ester.
  • Hydrolysis of the thiol ester, the designed
    product thiol can be obtained in good yield

89
4??????????
  • ?????????????????

90
4?????Gabriel???
  • ????????????

91
4????????????
92
5?????
  • ????????????????
  • ??????????????

93
????????????
  • The difference between carbon nucleophile and
    heteroatom nucleophile
  • 1. Carbon nucleophiles enter into relatively few
    SN2 reactions with sp3-hybridized carbon.
  • This is, in part, because they are much stronger
    bases and bring about competing elimination
    reactions.

94
????????????
  • They are sufficiently basic to abstract not only
    relatively acidic protons, such as those attached
    to heteroatoms, but also the much less acidic
    protons attached to carbon.
  • So,the more characteristic reactions of carbon
    nucleophiles are nucleophilic addition to
    sp2-hybridized carbon.

95
????????????
  • 2. Most of the carbon nucleophiles are highly
    reactive substances that are stable only in the
    absence of air and water.
  • Therefore, their use depends on the availability
    of more sophisticated laboratory techniques than
    are required for the manipulation of heteroatoms
    nucleophiles.

96
????????????
  • -CN ????????????
  • ???????????????????????????????
  • ????????????,??????????
  • ????????????????

97
????????????
  • 1????? Procaine
  • ??????
  • ??????????????????????(1884?)?????????????????????
    ??(Cocaine)??????,???,??????,???????,?????????????

98
????????????
  • ??????????????,?????????????????????????????

99
????????????
  • ??????????????,???????,????????????,?????????????,
    ?????????????????????,???1904?????????????????

100
????????????
  • ???
  • ????????????????

101
????????????
  • 2?????????????
  • Trifluperidol Hydrochloride

102
????????????
  • 3?????????? Phenobarbital

103
????????????
  • 4??????????
  • ( Sodium Valproate)
  • ?????????????

104
????????????
  • The difference between carbon nucleophile and
    heteroatom nucleophile
  • 1. ???????????,???????????????????,??????????sp2-?
    ?????,??????sp3-???????
  • 2. ???????????????,??????????????

105
????????????
  • -CN ????????????
  • ???????????????????????????????
  • ????????????,??????????
  • ????????????????

106
????????????
  • ????????????
  • 1?sp-?????- CN, RCC -
  • ???????????
  • ?????????????????????????(??6.6?)

107
????????????
  • 2? sp2 ?sp3??????? ???????? (?????)
  • ??????????
  • ??,???????????????????????????????????-??????,????
    ???????????????????
  • ??????????????????????????(????)?

108
????????????
  • 3?sp2 ?sp3???????
  • ??????? (Organometallic Compounds)
  • ????????????????????,????????????
  • ????????????????,??????
  • ??,??????????????

109
Organometallic Compounds
  • Formation of Organolithium and Organomagnesium
    Compounds
  • Organometallic compounds are formed by treatment
    of an alkyl halide or aryl halide with a
    zero-valent metal, usually lithium or magnesium.

110
Organometallic Compounds
111
Organometallic Compounds
  • The metal atoms in both organolithium and
    organomagnesium compounds coordinate particularly
    well with the oxygen atoms of ethers.
  • Therefore, ether such as THF or ethyl ether are
    commonly used as solvents for both the formation
    of organometallic reagents and their subsequent
    reactions.

112
Organometallic Compounds
  • Organomagnesium compounds are commonly called
    Grignard Reagents in recognition of the French
    chemist Francois Victor Grignard, who was honored
    in 1912 with the Nobel prize for his discovery of
    this class of compounds.

113
Organometallic Compounds
  • Note
  • The overall process of formation of Grignard
    reagent results in insertion of magnesium between
    the carbon atom and the bromine atom to which the
    carbon was originally attached.
  • Thus, the reaction in this way is often called as
    insertion reaction.

114
Organometallic Compounds
  • Reactions of Organolithium and Organomagnesium
    Compounds
  • They are generally poor nucleophiles with respect
    to alkyl halides and alkyl sulfonate esters,
    sp3-hybridized electrophile carbon species.
  • In addition, they are very strong bases and
    promote elimination reaction.

115
Organometallic Compounds
  • 1. With Epoxides ---- SN2 reaction
  • It is a good path way to obtain the increasing
    two carbon atoms alcohol
  • The C-O bonds of an epoxide are weaker than those
    of other ethers (why?). And they are weakened by
    the complexation betwwen the metal acting as a
    Lewis acid and the oxygen acting as a Lewis base.

116
Organometallic Compounds
117
Organometallic Compounds
  • 2. With compounds containing active-proton
    group(OH, NH, COOH)
  • ( ???????????,???????????? )
  • Reduction of Alkyl Halides
  • Isotopic Labeling

118
Organometallic Compounds
  • 3. Grignard Reagents reacting with CO2
  • ---- an good alternative method for obtaining
    carboxylic acid
  • ---- this is an addition reaction

119
Organometallic Compounds
  • 4. Lithium Dialkylcuprates
  • Unlike the organolithium reagents, lithium
    dialkylcuprates are excellent nucleophiles in
    reactions with alkyl halides and alkyl sulfonate
    esters.
  • Aryl halides and vinyl halides also react with
    them form C-C bonds. (not SN2)

120
Organometallic Compounds
121
Basic Skill Check
  • 1. Can I predict the product (including
    stereochemistry and regiochemistry), when given
    the reactants?
  • 2. Do I know the reagent(s) and conditions
    necessary to convert the given functional group
    into the product?

122
Basic Skill Check
  • 3. For a desired product formed by a given
    reaction path, can I correctly choose an
    appropriate starting materials?
  • 4. Given the reactants, conditions, and products,
    can I write a detailed reaction mechanism showing
    the specific electron flow that describes how the
    reaction proceeds?

123
??? ??????
  • ??????
  • 1. ????
  • 1)?????
  • ????gt??gt??gtCH4
  • ???????????????????????????

124
2). ??????-H???
125
???????,???N-??????(??NBS)
???????????HBr?Br2?????
126
??
127
(No Transcript)
128
2.???????(?)
  • 3.?????????(?)
  • ??????
  • ???????HX?PX3?PX5?????(???????SOCl2)

129
1.??????
????????NaX?????????
2.??????
130
3.???????

????????
131
Reading Assignment
  • ??
  • ??? ??????
  • ??? ?????(????)

132
Homework Assignment
  • P2522 4(125)5-1820
  • 212326
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