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Outline
● Introduction ▫History ▫Synthesis ▫Effect factor
● Improve the Friedel-Crafts Reaction ▫Change catalyst ▫Change solvent
● Applications of Friedel-Crafts Reaction ▫Poly(ether ketone) ▫ Dye
● Conclusions
3
Outline
● Introduction ▫History ▫Synthesis ▫Effect factor
● Improve the Friedel-Crafts Reaction ▫Change catalyst ▫Change solvent
● Applications of Friedel-Crafts Reaction ▫Poly(ether ketone) ▫ Dye
● Conclusions
4
History
Charles Friedel James Mason Crafts
(March 8, 1839 – June 20, 1917) (12 March 1832 – 20 April 1899)
French chemist and mineralogist American chemist
Charles Friedel and James Mason Crafts in 1877 to attach substituents to an aromatic ring
Friedel-Crafts Reaction
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Friedel - Crafts reaction temperature is generally less than 90 ~ 100 .℃
Temperature control can effectively reduce the side reaction.
High activity catalyst reactants still require the high temperature.
Temperature
Aromatic structure
O SN
> > > > >
H
The aromatic ring with electron donating groups is facilitate the reaction.
9Solvent
most common polar solventPhNO2 (acyl)CH3NO2 (alkylation) CH3CH2NO2
CH3NO2, PhNO2 ,CS2 are the best reaction solvent, but because the high toxicity should be avoided. 1,2 - dichloroethane and methylene chloride is also a good solvent.
most common non-polar solventCS2
CCl4
Lewis acid
Catalyst
The amount of catalyst: activity of the structure aromatics, acylating reagents reaction temperature
Brønsted acids Large amount of catalyst can not be recycled Must be used under anhydrous conditions Equipment corrosion Environmental pollution
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Friedel-Crafts Reaction
Advantage
Simple operation High efficiency and yield
Disadvantage
Large amount of catalyst can not be recycled Equipment corrosion Environmental pollution
To maintain selectivity, a long reaction time (hours) at a low temperature is necessary. The use of traditional liquid acid or Lewis acid catalysts and organic solvents cause
many problems in cost, apparatus and environment. After the reaction, the catalyst and the solvent have to be separated from the reaction
mixture and either purified for recycling or disposed of.
11
Outline
● Introduction ▫History ▫Synthesis ▫Effect factor
● Improve the Friedel-Crafts Reaction ▫Change catalyst ▫Change solvent
● Applications of Friedel-Crafts Reaction ▫Poly(ether ketone) ▫ Dye
● Conclusions
13
Rueping, M.; Nachtsheim, B. J.; Ieawsuwan, W. Adv. Synth. Catal., 2006, 348, 1033–1037
Change catalyst
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Change catalyst
Wang, B.-Q.; Xiang, S.-K.; Sun, Z.-P.; Guan, B.-T.; Hu, P.;Zhao, K.-Q.; Shi, Z.-J. Tetrahedron Lett. 2008, 49, 4310–4312.
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Outline
● Introduction ▫History ▫Synthesis ▫Effect factor
● Improve the Friedel-Crafts Reaction ▫Change catalyst ▫Change solvent
● Applications of Friedel-Crafts Reaction ▫Poly(ether ketone) ▫ Dye
● Conclusions
17
O
+
CCl
O
ClC
O
O C
O
C
O
AlCl3 AlCl3
O C
O
C
O
n n
AlCl3
DCE
5oC 2hR.T. 16h
MeOH
poly(ether ketone)
Yoshimitsu Sakaguchi*, Masaya Tokai and Yasuo Kato, POLYMER, 1993, 34, 7
Advantage Excellent wear resistance at high temperatures. Excellent hydrolysis resistance at high temperatures. High temperature performance for all mechanical properties. Excellent electrical performance at high temperatures. Excellent chemical resistance at high temperatures.
© Gharda Chemicals Limited.
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+ 2 Cl2 ClCl
H2S + 2 NaOH Na2S + H2O
poly(phenylene sulfide)
Advantages Excellent chemical resistance High temperature performance High modulus when reinforced
Ryton® / Techtron® / PPS (Polyphenylene Sulfide)
Special Topics on Polymers Synthesis lecture 3
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Dye
pH indicator9.3-10.5
Biological dye
James V. McCullagh* and Kelly A. Daggett, Journal of Chemical Education, 2007, 84,11
food coloring
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Outline
● Introduction ▫History ▫Synthesis ▫Effect factor
● Improve the Friedel-Crafts Reaction ▫Change catalyst ▫Change solvent
● Applications of Friedel-Crafts Reaction ▫Poly(ether ketone) ▫ Dye
● Conclusions
21
ConclusionsSimple operationUsed in many Organic SynthesesHigh efficiency and yield
Future work Green chemistryCatalystSolventEquipment corrosionEnvironmental pollution
Magnus Rueping and Boris J. Nachtsheim, Beilstein Journal of Organic Chemistry, 2010, 6, 1-24
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