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Syntheses, Characterization and Applications of Palladium Catalysts in Homogeneous, Heterogeneous and Hybrid Forms. 演講者 : 李俊欽 指導老師 : 于淑君 教授. Part 1 :. The Catalytic Activities of the Palladium Nanoparticles in o-Xylene and Ionic Liquids. Pd NPs. Heck Reactions. - PowerPoint PPT Presentation
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1
Syntheses, Characterization and Applications of Syntheses, Characterization and Applications of Palladium Catalysts in Homogeneous, Palladium Catalysts in Homogeneous,
Heterogeneous and Hybrid FormsHeterogeneous and Hybrid Forms
演講者 : 李俊欽
指導老師 : 于淑君 教授
2
Part 1 : The Catalytic Activities of the Palladium Nanoparticles in o-Xylene and Ionic Liquids
Pd NPs
NN
H3C
CH3PF6
-
(Pd NPs)
Oganic phase
Ionic liquid
Oganic phase
Ionic liquid
NN
H3C
CH3PF6
-
Extraction
Heck Reactions
R
R'
+ Pd NPsI
R = Ph, CO2nBu, CO2
tBu, CO2Et,CO2Me
R' = H, OMe
NPr3, 140 oC, R'
R
3
Palladium-Catalyzed ReactionsPalladium-Catalyzed Reactions
Pdcatalyst
Heck-, Suzuki-,Diels-Alder etc
C-C coupling : Hydrogenation Other reactions
H2
Oxidation etc
4
Types of Pd CatalystsTypes of Pd Catalysts
N P
Pd
PPh2
N
But
But
X
X
PPh2
Pd
Ph2P
Cl
Cl
Whitcombe N. J., Hii K. K., Gibson S. E. Tetrahedron 2001, 57,7449.
HomogeneousHomogeneous
Hetrogeneous Hetrogeneous
Pd/SiO2, Pd/C, Pd/SiO2, Pd/C, Pd/AlPd/Al22OO33, Pd/resin,, Pd/resin,
Pd-modified zeolitesPd-modified zeolites
Pd Nanoparticles (Pd NPPd Nanoparticles (Pd NPs)s)
5
The Advantage of Nanoscale CatalystsThe Advantage of Nanoscale Catalysts
Rao, C. N. R. Chem. Soc. Rev., 2000, 29, 27–35
A nanoparticle of 10 nm diameter would have A nanoparticle of 10 nm diameter would have ~ 10% of atoms on the surface, compared to n~ 10% of atoms on the surface, compared to n
early 100% when the diameter is 1 nm.early 100% when the diameter is 1 nm.
6
What Are Ionic Liquids?What Are Ionic Liquids?
• Ionic liquids are salts liquids that are composIonic liquids are salts liquids that are composed entirely of ions.ed entirely of ions.
• Room Temperature Ionic Liquids Room Temperature Ionic Liquids :: meltimelting points ~ng points ~ 100 °C, and sometimes as low as100 °C, and sometimes as low as -96 °C -96 °C
7
Catalysis in Ionic LiquidsCatalysis in Ionic Liquids
General Considerations General Considerations • no vapor pressureno vapor pressure• thermal stabilitythermal stability• much greater dissolution capability toward mmuch greater dissolution capability toward m
ost organic, inorganic and organometallic coost organic, inorganic and organometallic compounds.mpounds.
• high solubility for gaseous moleculeshigh solubility for gaseous molecules• immiscible with some organic solvents,immiscible with some organic solvents,• a “designer solvents”.a “designer solvents”.
9
The Applications of Pd NPs in Ionic LiquidThe Applications of Pd NPs in Ionic Liquid
Dupont, J. J. Am. Chem. Soc. 2005, 127, 3298-3299.
10
Ionic Liquid Ionic Liquid & & Phase TransferPhase Transfer
NN
H3C
CH3PF6
-
(gold NPs)
Aqueous phase
Ionic liquid
Aqueous phase
Ionic liquid
NN
H3C
CH3PF6
-
Extraction
Wei, G. T. J. Am. Chem. Soc. 2004, 126, 5036-5037
11
MotivationMotivation
To study Pd NPs as catalysts for Heck reactions in both molecular solvents and room temperature Ionic Liquids.
13
Syntheses of Pd NPsSyntheses of Pd NPs
OO
OO
Pd
H
H
CF3CF3
CF3CF3
Pd(hfac)2 : Dihexafluoroacetylacetae Palladium(II)
Pd(hfac)2 (Pd(0))n140 oC reflux 3hr
o-xylene 20 mL
14
The TEM Image of Pd NPsThe TEM Image of Pd NPs
12 14 16 18 200
10
20
30
40
50
prop
ortio
n
size (nm)
Particle size distribution = 16.8 ± 1.4 nm
15
Preparation of bmimPFPreparation of bmimPF6 6 Ionic LiquidIonic Liquid
N NH3C
ClN N
H3CCH3+
80¢J
48hrCl -
N NH3C
CH3
Cl -+ KPF6 N N
H3CCH3
1. stir 30 mins
2. wash with H2OPF6
-
1-butyl-3-methylimidazolium hexafluorophosphate ([bmim] +PF6-)
McEwen, A. B. Thermochim. Acta 2000, 357, 97-102.
16
General Catalyses of Heck Reaction General Catalyses of Heck Reaction
R
R'
+ Pd NPsI
R = Ph, CO2nBu,
CO2tBu,CO2Et,CO2Me
R'=H, OMe
NPr3, 140 oC, R'
R
Pd mmol
Pd mmol ¡Ñ reaction time (hr)
Product mmol
Product mmol
TON
reaction time (hr)=
TON
TOF
=
=
18
Yield vs. Reaction TimeYield vs. Reaction Time產率對反應時間趨勢圖
0
10
20
30
40
50
60
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
time(hr)
Yield
0.00025 mole %
0.00038 mole %
0.0005 mole %
0.00075 mole %
0.001 mole %
0.002 mole %
COOEt+Pd NPs
I
140 oC, NPr3
COOEt
19
TOF vs. Reaction TimeTOF vs. Reaction TimeTOF值對反應時間趨勢圖
0
5000
10000
15000
20000
25000
30000
35000
40000
45000
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15time(hr)
TOF
0.00025 mole %
0.00038 mole %
0.0005 mole %
0.00075 mole %
0.001 mole %
0.002 mole %
COOEt+Pd NPs
I
140 oC, NPr3
COOEt
19
20
R1 R2 Yield (%) TON TOF
H
CO2Et 76 143049 31788
CO2-n-Bu 53 101269 22504
CO2-t-Bu 40 75322 16738
CO2Me 35 66778 14839
Ph 16 31582 7018
OMe
CO2Et 48 90510 20113
CO2-n-Bu 56 105197 23377
CO2-t-Bu 43 80832 17963
CO2Me 31 59075 13128
Ph 4 8770 1949
R2
R1
+
Pd NPs 0.0005 mole %
I
NPr3, 140 oC, reflux for 4.5 hr R1
R2
21
R1 R2 time ( hr ) yield (%)
H
CO2Et 6 81
CO2-n-Bu 6 94
CO2-t-Bu 16 87
CO2Me 24 93
Ph 48 52
OMeCO2Me 36 98
Ph 36 41
R2
R1
+
Pd NPs 0.0005 mole %
I
NPr3, 140 oC, reflux R1
R2
22
Pd loading (mole %)yield
( % ) TON TOF
0.0010 5 4832 1381
0.0020 28 13196 3770
0.0025 55 20669 5906
0.0030 61 19080 5451
0.0035 65 17505 5001
0.0040 70 16384 4681
0.0050 76 14192 4055
0.0060 77 11961 3417
COOEt+
Pd NPs in 1mL ionic liquid
I
NPr3, 140 oC, reflux for 3.5 hr
COOEt
23
產率對Pd添加量趨勢圖
0
10
20
30
40
50
60
70
80
90
100
0 0.001 0.002 0.003 0.004 0.005 0.006 0.007
Pd loading ( mole % )
Yi el d
3.5 hr
Yield Yield vs.vs. Reaction Time Reaction Time
COOEt+
Pd NPs in 1mL ionic liquid
I
NPr3, 140 oC, reflux for 3.5 hr
COOEt
23
24
TOF TOF vs. vs. Reaction TimeReaction Time
轉化率(TOF)對Pd添加量趨勢圖
0
1000
2000
3000
4000
5000
6000
7000
0 0.001 0.002 0.003 0.004 0.005 0.006 0.007
Pd loading ( mole % )
TOF
3.5 hr
COOEt+
Pd NPs in 1mL ionic liquid
I
NPr3, 140 oC, reflux for 3.5 hr
COOEt
24
25
LiquidsLiquids Viscosity (cP)Viscosity (cP)
oo-Xylene-Xylene 0.8090.809
WaterWater 1.01.0
bmimPFbmimPF66 300300
• Decomposition of ILDecomposition of IL• Viscosity of ILViscosity of IL• Dispersion of Pd NPs in ILDispersion of Pd NPs in IL
Causes of the Low Activity for IL SystemCauses of the Low Activity for IL System
26
EntryEq.of base vs. ionic liquid
Pd conc. (mM)
Time( hr )
Yield( % ) TON TOF comment
1 1.0 0.0393 4 27 5164 1291 Absolute concentrationsare diluted.2 5.0 0.0393 4 46 8658 2164
3 1.0 0.0571 4 10 3362 840
Absolute concentrationsare the same.
4 2.5 0.0571 4 73 22892 5723
5 1.0 0.0571 6 40 12561 2093
6 2.5 0.0571 6 85 26692 4448
COOEt+
Pd NPs in 1mL ionic liquid
I
NPr3, 140 oC, reflux
COOEt
Effects of BaseEffects of Base
27
ConclusionConclusion
• The catalytic reactivity in term of TOF could be increased by reducing the Pd-to-substrate mole ratio and also by extending the reaction time.
• The catalytic activity of Pd NPs in bmimPF6 ionic liquid is restrained due to poor particle dispersion in ionic liquid.
• The catalytic activity of Pd NPs in ionic liquid can be enhanced by adding more base to the system.
28
I RR
+RS-Pd(0)-Pd(II)
115 oC / 1.5 h
R = Ph, CO2nBu, CO2
tBu, CO2Et,CO2Me
Pd(0)-Ligand-Pd(II)Cl2
*#
-HNCH2-py
NH
-CH3
The Syntheses and Applications of the Palladium(II) Catalyst Supported on Palladium Nanoparticles
Part 2 :
29
Characteristics of catalysts
Homogenous Heterogeneous Hybrid
Cat. structure Known Unknown Known
Catalyst modification Easy Difficult Easy
Activity High Low High
Selectivity High Low High
Poisoning of cat. High risk Low risk Low risk
Mechanical strength Low High High
Cat. stabilities Low High High
Conditions of catalysis Mild Harsh Mild
Separation & recycle of cat. Difficult Easy Easy
Industrialization Difficult Accessible Accessible
Types of CatalystsTypes of Catalysts
30
functional groups
spacer linker
Catalysts
coordination ligands
Homogeneous cat.
= W, Mo,Cr, Pd, Pt, etc.
SupportsBulk surfaceNano surface
The Componemts of Hybrid CatalystThe Componemts of Hybrid Catalyst
31Jang, S. Tetrahedron Lett. 1997, 38, 1793.
Polystyrene-Based Supports :Polystyrene-Based Supports :
32
Silica-Supported Catalysts :Silica-Supported Catalysts :
Kinzel, E. J. Chem. Soc. Chem. Commun. 1986 1098
34
(EtO)3SiN
PPh2
PPh2
NC
O
H
O2
Oxidation
(EtO)3SiN
PPh2
PPh2
NC
O
HO
O
SiN
PPh2
PPh2
NC
O
H
OO
OEt
+RhL2
SiN
PPh2
PPh2
NC
O
H
OO
OEt
RhL2
O2 O
O
Metal Leaching
a. Oxidation
b. Metal Leaching
The Limitation of Phosphine Ligand The Limitation of Phosphine Ligand
Kinzel, E. J. Chem. Soc. Chem. Commun. 1986 1098
35
Bipyridine LigandBipyridine Ligand
CMe2Ph
CMe2Ph
O N
N
N
O
N N N
H2PdCl4m
m
n
n
interior
surface
CMe2Ph
CMe2Ph
ON
N
N
O
N N
N
Pd2+
Pd2+
m
m
n
n
Buchmeiser, F. M. R. J. Am. Chem. Soc. 1998, 120, 2790.
Poly(N,N-bipyridyl-endo-norborn-2-ene-5-carbamide)10
36
• To study the immobilization of molecular Pd(II) complexes on the surfaces of Pd NPs by using the covalent techniques via a specially designed bipyridylphosphinicamidol thiol as spacer ligands.
• To investigate the reactivity of hybrid catalyst of
this type on a series of heck reaction and look into any possibility of reactivity changes due to the process of immobilization.
MotivationMotivation
38
Synthesis of Spacer-LinkerSynthesis of Spacer-Linker
1. NaN3 / DMF2. r.t. / 6hr
1
3
1. CS(NH2)2 / ethanol
2. reflux , 16 hr
3. NaOH / 5 min4. HCl /20 min
Br(CH2)11OH92 %
N3(CH2)11OH
1. (CF3CO)2O / THF2. LiBr / THF3. HMPA4. 80oC / 6 hr
2
N3(CH2)11Br
N3(CH2)11SH
86 %
80 %
1. P(2-py3) / CH3CH2CN2. 100 0C / 16 hr
75 %HS(CH2)11N(H)(O)P(2-py)2
4
39
Synthesis of Molecule CatalystSynthesis of Molecule Catalyst
N3(CH2)11OH
1HO(CH2)11N P
N
N
O
5
1. P(2-py)3 / CH3CN2. 1 mL H2O
3. reflux , 16 hr
75%
Pd(CH3CN)2Cl2
CH3CN / rt, 3hrHO(CH2)11N P
N
N
O
6
PdCl25
40
Synthesis of Octanethiol Protected Pd NPs Synthesis of Octanethiol Protected Pd NPs 88
1. surfactant [CH3(CH2)7]4N+Br- / CHCl32. Sodium citrate / H2O
3. reflux for 1 dayPdCl2(CH3CN)2
n-octanethiolr.t / stir for 1 hr
Pd
N+
N+N+
N+
Br-
Br-
Br-
Br-
Pd(0)-TOAB (7)
Pd
HSSH
HS
Pd(0)-SR (8)
41
Pd(0)-TOAB (7)
TOAB
Ligand(4)
CHCl3 / 70 oC
TOABHS
(py)2
octanethiol
HS
(py)2
SH
SH
(py)2PdCl2
HS
PdCl2(CH3CN)2
EtOH
ppt.
redispersed in EtOH
redispersed in DMSO
ppt.Soluble Pd(0)-Ligand-Pd(II)Cl2 NPs
HS
(py)2
HS
(py)2
HS
(py)2PdCl2
SH
(py)2PdCl2
HS
HS
(py)2PdCl2
TOABTOAB
Pd(0)-Ligand (9)
(10)
Pd
Pd
Pd Pd
Pd
Synthesis of Pd(II)-Immobilized Pd NPs Synthesis of Pd(II)-Immobilized Pd NPs 1010
42
TEM Images of TOAB TEM Images of TOAB Protected Pd NPs (Protected Pd NPs (77))
Particle size distribution = 4.1 ± 1.12 nm
Pd
N+
N+N+
N+
Br-
Br-
Br-
Br-
TOAB Protected Pd NPs (7)
43
TEM Images of TEM Images of Octanethiol Protected Pd NPs Octanethiol Protected Pd NPs ((88))
Particle size distribution = 4.52 ± 1.32 nm
Pd
HSSH
HS
Octanethiol Protected Pd NPs (8)
44
TEM Images of TEM Images of Pd(0) –LigandPd(0) –Ligand ( (99))
Particle size distribution = 4.43 ± 1.09 nm
Pd
HS
(py)2
SH
HS
(py)2
Pd(0) ¡VLigand (9)
45
TEM Images of TEM Images of Pd(0) –LigandPd(0) –Ligand-Pd(II)Cl-Pd(II)Cl22 ( (1010))
Pd (0)-Ligand-Pd (II)Cl2
SH
(py)2PdCl2
SH
HS
(py)2PdCl2
(10)
Pd
Particle size distribution = 4.60 ± 1.26 nm
46
(a) HS(CH2)(CH2)(CH2)6CH3 (n-octanethiol, HSR)
(b) Pd-S(CH2)7CH3 (Pd-SR)(8)
(c) HS(CH2)11N(H)(O)P(2-py)2 (Ligand(4))
(d) RS-Pd-S(CH2)11N(H)(O)P(2-py)2 (Pd-Ligand)(9)
α H
CDCl3*
-CH3
py*
-HNCH2-
# -CH3
py -HNCH2-*
β H
β H
β Hα H
β H
-CH3
NMR Spectra of Pd NPs NMR Spectra of Pd NPs 88 & & 99
α β
45
47
NMR Spectra of Pd NPs NMR Spectra of Pd NPs 99 & & 1010
(b) HO(CH2)11N(H)(O)P(2-py)2PdCl2 (6)# -CH2OH
- HNCH2-
*NH
py
(c) RS-Pd-S(CH2)11N(H)(O)P(2-py)2 (Pd-Ligand)(9)
py
NH
-HNCH2-
# *
d6-DMSO
*#
-HNCH2-
(d) RS-Pd-S(CH2)11N(H)(O)P(2-py)2PdCl2 (Pd(0)-Ligand-Pd(II)Cl2)(10)
py
NH
-CH3
-CH3
(a) HS(CH2)11N(H)(O)P(2-py)2 (Ligand(4))
NH
-HNCH2-
# *py
46
49
IR Spectra of Ligand IR Spectra of Ligand 44, , Pd Nanoparticles Pd Nanoparticles 99 & & 1010
1575 (py)
1585 (py)
48
52
UV-vis Spectra of Molecules UV-vis Spectra of Molecules 44, , 55, , 66 & & Pd Nanoparticles Pd Nanoparticles 88, , 99, , 1010
53
Nanoparticle Size (nm)Pd(0) total / Pd(0)sur / n-octanethiol / Ligand 4
( mole ratio )
Pd(0)-SR (8)4.52 ± 1.32
1 / 0.30 / 0.78 / 0
Pd(0)-ligand (9)
4.43 ± 1.09
1 / 0.31 / 0.15 / 0.12
Pd(0)-ligand-Pd(II)Cl2 (10)
4.60 ± 1.26
1 / 0.29 / 0.05 / 0.04
Analytical data of Analytical data of Pd Nanoparticles Pd Nanoparticles 88, , 99 & & 1010
54
Cat. R Yield (%) TOFa TOFb
Pd(0)-ligand-Pd(II)Cl2 (10)
CO2Me 81 2200 7007
CO2Et 81 2213 7049
CO2-n-Bu 82 2241 7132
CO2-t-Bu 69 1885 5982
Ph 40 1093 3468
Pd(0)-Ligand (9)
CO2Me 71 2023 6754
CO2Et 77 2194 7325
CO2-n-Bu 82 2336 7800
CO2-t-Bu 73 2080 6944
Ph 42 1197 6995
Pd(0)-SR (8)
CO2Me 72 2051 6849
CO2Et 66 1880 6278
CO2-n-Bu 67 1909 6373
CO2-t-Bu 63 1795 5993
Ph 25 712 2378
I
+ Rcat.
115 oC,NEt3 / DMSO, 1,5 hr
R
R = phenyl, COOR' (R' = Me, Et, n-Bu, t-Bu)
Pd(II)=1 × 10 -7 mole ; Pd(0) = 2.34 × 10 -6 mole ; reactant 1 = reactant 2 = 0.01 mole ; temp. = 115 ; solvent = DMSO (1 mL) ; base = NEt℃ 3 ( 1.5 mL) ; a cat. = Total Pd(0) + Pd(II) ; b cat. = Surface Pd(0) + Pd(II)
55
R Cat.Yield(%) TOFa TOFb
CO2-n-Bu
Pd(0)-ligand-Pd(II)Cl2 (10) 72 1976 6431
Pd(0)-SR (8) 52 1481 4944
Pd(0)-SR + (6) 54 1478 4504
HO(CH2)11N(H)(O)P(2-py)2PdCl2 (6) n.d. 00 00
PdCl2(CH3CN)2 n.d. 00 00
PdCl2(CH3CN)2c 93 6200 6200
I
+ Rcat.
115 oC,NEt3 / DMSO, 1,5 hr
R
R = phenyl, COOR' (R' = Me, Et, n-Bu, t-Bu)
Pd(II)=1 × 10 -7 mole ; Pd(0) = 2.34 × 10 -6 mole ; reactant 1 = reactant 2 = 0.01 mole ; temp. = 115 ; solvent = DMSO (1 mL) ; base = NEt℃ 3 ( 1.5 mL) ; a cat. = Total Pd(0) + Pd(II) ; b cat. = Surface Pd(0) + Pd(II) ; c Pd(II)=1 × 10 -6 mole
56
R Cat.Times of total
substrates and cat. Yield(%) TOF
CO2-n-
Bu
PdCl2(CH3CN)2
1 × n.d. 0
2 × 7 4667
3 × 11 7500
HO(CH2)11N(H)(O)P(2-py)2PdCl2 (6)
1 × n.d. 0
2 × 3 1693
3 × 8 5063
Pd(0)-SR + (6) 3 × 98 8354a
Pd(0)-ligand-Pd(II)Cl2 (10) 3 × 94 8014a
Pd(0)-ligand-Pd(II)Cl2 (10)
(cat. in xylene for heterogeneous catalyses )1 × 5 391a
Pd(0)-ligand-Pd(II)Cl2 (10)
(reflux condition )1 × 71 5991a
I
+ Rcat.
115 oC,NEt3 / DMSO, 1,5 hr
R
R = phenyl, COOR' (R' = Me, Et, n-Bu, t-Bu)
a cat. = Surface Pd(0) + Pd(II)3 × : Pd(II)=3 × 10 -7 mole; Pd(0) = 7.02 × 10 -6 mole; reactant 1 = reactant 2 = 0.03 mole ; temp = 115 ; solvent = DMSO (3 mL); base = NEt3 ( 4.5 mL)℃
57
Pd(0)-Pd(II)Cl2 (10) before heating in 115 oC for 1.5 hr
Pd(0)-Pd(II)Cl2 (10) after heating in 115 oC for 1.5 hr
59
0 1 2 3 4 5 6 7 8 9 10
Diameter (nm)
Cou
nt
Pd(0)-Pd(II)Cl2 (10) before heating Pd(0)-Pd(II)Cl2 (10) after heating
Particle size distribution = 4.57 ± 1.19 nm
Particle size distribution = 4.91 ± 1.28 nm
60
ConclusionConclusion• We use biphasic-synthesis method to prepair the s
urfaces-modifiable TOAB protected Pd NPs. • We have developed a method to successfully imm
obilize molecular Pd(II) complexes catalysts onto the surfaces of Pd NPs.
• Since the Pd NPs-Pd(II) hybrid catalysts are highly soluble in organic solvents, their structures and reactions could be easily studied by simple solution NMR technique.
• The Pd NPs-Pd(II) complexes were proven to be highly effective catalysts for a series of Heck reactions.
61
(6) in CDCl3 before catalyze 3-hexyne heating for 1 day in 70 oC
(6) in CDCl3 after catalyze 3-hexyne heating for 1 day in 70 oC
62
(6) in CDCl3 before catalyze 3-hexyne heating for 1 day in 70 oC (zoom in)
(6) in CDCl3 after catalyze 3-hexyne heating for 1 day in 70 oC (zoom in)
67
IR Spectra of n-Octanethiol & Pd NPs (IR Spectra of n-Octanethiol & Pd NPs (88))
2853 (νs CH2)
2922(νs CH3 、 νas CH2)
2956 (νas CH3)
1462(δs CH2 、 δas CH3)
1375(δs CH3)
722(ρ CH2)
68
IR Spectra of Ligand(IR Spectra of Ligand(44), ), Pd Nanoparticles (Pd Nanoparticles (99) & () & (1010) )
2848 (νs CH2)
2921(νas CH2)
1575 (py)
1585 (py)
69
entryentry 鹼相對於離子液鹼相對於離子液體之當量數體之當量數
Pd Pd 添加添加量量 ((mm
LL))
反應時間反應時間(( hhrr ))
產率產率(%)(%) TONTON TOFTOF
11 11 1.01.0 44 2727 51645164 1291 1291 體積、濃度相等但絕對濃度被稀釋
22 55 1.01.0 44 4646 8658 8658 21642164
33 11 0.60.6 44 1010 3362 3362 840840
絕對濃度相同
44 2.52.5 1.21.2 44 7373 22892 22892 5723 5723
55 11 0.60.6 66 4040 12561 12561 20932093
66 2.52.5 1.21.2 66 8585 26692 26692 4448 4448
70
1
62.5
01.0
)(1)(62.4
01.0
62.5
01.0
)(1)(2)(12.1)(5.1
)(01.0
xy
dIonicLiquibasesubstratexy
x
dIonicLiquibasexIodobezenexateethylacrylxy
Iodobezenex
71
Heck Reaction
Z
X
R
Pd catalysts
Base
R
Z+
X=Cl, Br, IZ=COOR, Ph
Mizoroki, T. Chem. Soc. Jap., 1971, 44, 581