工业有机合成-课件

A: Chain initiation B: Chain transfer
C: Chain termination
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h eato rrayrad iatio n
RH
R+H
1. The chain initiation
R H+M n+
R + H+M (n-1)+
R H +X
R + H X
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2. The Chain transfer
Chapter 9 Oxidation-Reduction Reactions and their Industrial Possibilities
9.1 General Introduction of oxidation
C H 2 C H 2
O
➢ +O in organic compounds
C H 3 toluene
R + O 2
ROO
R O O + R H
R O O H
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3. The chain termination
R +R
RR
R O O + R
R O O R
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9.2.2 The elements of influence the automatic oxidation 1. Initiation agents and catalytic
Automatic react ＋ O2
The reaction very slow
Increasing the reaction
＋
Catalytic or initiation agent
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Typical free radical chain-style reaction
The automatic oxidation
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9.2 Air liquid phase oxidation reactions
Definitir is flowed into the organic compound in liquid phase under the action of catalytic, then the compound is oxidized, this kind of reaction has been called the air liquid phase oxidation reaction
requirement
A: special reactor：air-flowing-style reactor B: catalytic (soluble in the organic liquid)
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9.2.1 The reaction process
Some organic compounds
O
H 2C C H 2
O
Epoxy-ethane
C O O H
1. The reaction types
➢ both -H and +O in organic compounds
O
O
O
O
➢ organic compounds oxidation and decomposition
R C H 3
O
R C N Cyano-compound
➢ organic compounds ammoniac-oxidized
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2. can be made by the oxidation reactions
ROH
O
RCH
O
R C OH
O
O
HO C O C OH
R
O Epoxy-compound
OH
R CN Cyano-compound
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3. The general features of the oxidation reactions
1）The oxidizing agents
The gas phase oxygen O2 cheaper, without the instrument damage, but lower oxidizing –ability need catalytic.
Oxygen atom [O] generated from the chemical oxidizing agents, high oxidizingabilities, high selection, mild reaction conditions, but high cost.
3.The influence of the anti-reactive （阻化）agents
The anti-reactive agents can react with the free radicals to form the stable compounds, and to result the chain termination; and few quantity of the agents can also make the oxidation process slowing down.
CH3
CH
O
CH3
CH3
C+ H
CH3
The energy order as follows: The third C-H ＜ the second C-H ＜ the first C-H, thus , the oxidation first occur at the third C atom.
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3
2) Strong heat releasing reactions
3) Unconverted reaction
X
4) Multi-reaction ways and with by-reactions In order to obtained the target oxidized compound, the suitable way must be selected
1) + initiation agent →the organic compound to be oxidized easy
2) + catalytic ( the transitional metal ion, such as: Co2+ , Mn2+, Fe3+, V5+ etc.) → the activation energy of the organic compound to be reduced
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The organic compounds’ C-H bonds to be broken are relative to the energy of these bonds
2. The influence of the oxidized organic compound’s structure