Novozym 435 & porcine pancreatic lipase in tetrahydrofuran
No reaction occurred in the hydrophilic ILS investigated, eg BMIMNO3
J.Am.Chem.Soc., 2003, by A.J. Russell et al
Catalysis Organic synthesis
Heack, Beckmann etc
life sciences
Artificial muscle, drug reservoirs
At least another 500 papers will appeared by the end of 2003
Good electrechemical satbility: E. W. ca 5V reasonably good electrical conductivity (25 mS/cm)
ILs contaning 1-alkyl-3 methylimidazolium cations
High thermal stability > 400 oC
At 50 oC in the presence of DVA and BD
+
+
The use of ILs to replace organic solvents in biocatalytic processes has recently gained much attention (
O O
n HO Butanediol
OH
BD
2n-1
OH
)n
CH3CHO
2. PROGRESS:Catalysis with ILs — Functional ILs Recently, functional ILs,eg Bronsted acidic ILs used as solvent-catalyst were developed
O O
divinyl adipate
DVA
O O O
lipase
Polyester
O
Novozym 435 & porcine pancreatic lipase in BMIMPF6
Lipase-Catalyzed Polytransesterification of DVA and BD
The figure illustrates Lipase possess higher activity and stability in BMIMPF6 IL than that in tetrahydrofuran
Sulfonic acid group was incorporated
Solid acids, due to non-volatility, are being more widely used, but they have J.Am.Chem.Soc., 2002, by shortcomings as well J.H. Davis, Jr. et al Such Bronsted acidic IL has negligible vapor pressure, and is some kind of ‘solidlike’ liquid acid O
Such Bronsted acidic ILs is also an effective catalysts for esterification of OH
O
+
O O
Nearly 100％ of ester selectivity achieved
1. INTRODUCTION:What are ionic liquids
Room temperature ILs contain organic cations and inorganic anions
Typical cations
R2 R1 N R5 N R3 R4
Typical anions
1. INTRODUCTION: General situation of ILs research
There has been much work performed on ILs as reaction media or functional materials
The figure illustrates the growth in publications on ILs
R3 R2 N R6 R1
R4 R5
[AlCl4]Chloroaluminate [CF3COO][CF3SO2][BF4][PF6][(CF3SO2)2N]-
Reactive to water First generation ILs
N-alkyl imidazolium
R1 + N R4 R2
N-alkyl pyridinium
R2
Functional groups e.g. X=NH2, SO3H, CO2H, etc. incorporated upon the side chain of Imidazolium
R1
New !
N N R-X
[AuCl4][PdCl4]2-
Functional ILs
Third generation ILs
R5
R4
1. INTRODUCTION: Properties of ionic liquids ILs possess some special physical and chemical properties
Strong coulombic force: Much different from molecular solvents Lower melting point: ＜-90 oC Negligible vapor pressure: Green solvents Large liquid range ＞200 oC Designable: Acidity, Density, Hydrophility Selective dissolvability: ‘liquid’ zeolite Diversity: over a trillion possible
Electro chemistry
Electrolytes,
Electrodeposition
Clean energy
Electrolytes for solar cell, battery
Nano technology
Nano-metal particles, film
ca. 200 papers have appeared on the 226th ACS National Meeting
Higher aldehyde selectivity Higher ratio of the linear : the branched
A diagram of continuous-flow hydromylation in a Sc CO2-IL biphasic system Science, 2003, by D. J. Cole-Hamilton
R1 R4 + P R2 R3
Air and water stable Decreasing coordinating abilibity Increasing hydrophobicity Second generation ILs
R3
quaternary ammonium
quaternary alkylphosphonium
Isolation of desired products can be obtained by a simple distillation
The IL could be reused
2. PROGRESS:Catalysis with ILs — Combination with Sc CO2
+
Ni complex ionic liquid
Typical Difasol process: butenes dimerization to octenes based on nickel(II) salt in ionic liquid.
Phase separator
IFP claim that the Difasol process was much better than other dimerisation processes and without any other solvent Difasol reaction section A continuous run has been carried out over a period of 5500 h, and butene conversion and selectivity were stable Separation of IL and product occurs rapidly and completely due to insolubility
PROGRESS:Catalysis with ILs — Dimerization of alkenes The Institut Francais du Pé trole, IFP launched the first commercial process based on ILs, known as the Difasol process
Catalysis with Ionic Liquids: Progress and Prospects
Youquan DENG
Centre for Green Chemistry and Catalysis