Sponsored Links
This presentation is the property of its rightful owner.
1 / 79

第八章 卤代烃 PowerPoint PPT Presentation


  • 67 Views
  • Uploaded on
  • Presentation posted in: General

第八章 卤代烃. 烃分子中的一个或多个氢原子被卤原子取代后所生成的化合物称为卤代烃 R-X 卤代烃有很多用途,可用作溶剂、农药、制冷剂、灭火剂、麻醉剂、防腐剂等。 一卤代烃的性质比较活泼,能发生多种化学反应,转化成各种其他类型的有机化合物,所以,在烃中引入卤原子是改造分子性能的第一步加工,卤代烃在有机合成中起着桥梁的作用。. 第一节 卤代烃的分类和命名. 一、分类. 卤代烯烃和卤代芳烃的分类. 二、命名. 1. 卤原子作取代基,编号从离卤原子最近的一端开始,取代基按 “ 次序规则 ” 较优基团在后列出。对卤原子,较优基团编号较大。

Download Presentation

第八章 卤代烃

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


RX




1.

2.


  • 1.

  • 2.

  • 3.

  • 4.1

RF RCl RBr RI

1.82 1.94 1.79 1.64


(nm) 0.139 0.176 0.194 0.214

(kJ/mol) 456 351 293 243

CX


1.

NuOHNH3


a


b

c

d





>>>>


RI RBr RCl RF


:

:

1,1


13



Saytzeff Rule:


3.

1.

Wurtz


Corey-House


2).Grignard


Grignard


Grignard


Grignard

RLiRNa>RMgX>RZnX>R2Cd


4.

(1)H2NiPdPt

(2)LiAlH4NaBH4 Zn/HCl


LiAlH4NaBH4

LiAlH4 NaBH4

COOH CHO CHO

COOR RCOR RCOR

NO2CN


. (Reaction Mechanism)

1. SN1

2. SN2

3.

.

1. SN2

2. SN1


.

1.

2. (L)

3. (Nu:)

4.

.

.


.

1. ( SN 1)



SN 1

2. ( SN 2)


T

, T.


L

Nu

S N 2


p p

SN 2

3.

SN1 SN2

SN1


a

b

c


Nu

L

3.

SN2

Walden

+ L-

Nu:


(R) - (-) - 2 -

[]25D= -34.25

=100%

(S) - (-) - 2 -

[]25D= -9.90

=100%


SN1

(Racemization)


SN1

C+L

Nu: L


.

1

SN 2

> > >


SN 2

Nu:


R

Et

i-pr

CH2=CH-CH2

PhCH2

Ph2CH

Ph3C

SN1

A.

SN 1

(k1)

0.26

0.69

0.86

100

~10 5

~10 10

I

C

SN 1,


C2H5OCH2Cl

C-C-C-C-Cl

C2H5O-CH2CH2Cl

(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


SN1SN2

SN1p


SN1SN2

  • SN2


SN1


2

Nu: SN2

1

OH > H2O, CH3O- > CH3OH

2

A.

RO- > HO- >> RCO2- > ROH > H2O

CH3O- > PhO- > CH3CO2- > NO2-


F- < Cl- < Br- < I-

R - O - < R - S - < R - Se -

D.


C2H5O- > I-

I- > C2H5O-

B.

H2N- > OH- > F-

C.


TsOH

MsO-

CF3SO3-

b)

F

Cl

Br

I


3 (Leaving groups)

a)

pKa < 5

I- HI


4

CCl4,, CS2,

0

EtOH, H2O, CH3COOH

THF, Et2O, DMF, DMSO,

HMPT

0


SN 1

SN 2

SH- > CN- > I- > OH- >

N3- > Br- > CH3CO2- > Cl - > F- > H2O


SN 2

(Polar Aprotic Solvents)

Nu:


X -

F - > Cl - > Br - > I -

SN 2

k2

DMF 3 103

CH3OH 3 10-2


12

CO2OOH

ORNR2Xetc.


(SN2)


1 Procaine

1884Cocaine



1904


1.

1

>>>CH4


2). -H


N-NBS

HBrBr2



2.

3.

HXPX3PX5SOCl2


1.

NaX

2.


3.


  • Login