Chemical Catalysis- JJ-2025
Chemical catalysis
Inhoud
Lecture 1: Introduction, basic principle, refreshing ...................................................................2
Lecture 2: Catalytic homogeneous hydrogenation/enantioselective catalysis .......................... 17
Lecture 3: Case study ............................................................................................................ 25
Lecture 4: Cross-couplings .................................................................................................... 27
Lecture 5: Cross-coupling --Part 2 Lecture 4 ....................................................................... 38
Lecture 6: Case study 2 ......................................................................................................... 47
Lecture 7: CH activation ........................................................................................................ 53
Lecture 8—part 2: Metathesis ................................................................................................ 60
Lecture 9: Organocatalysis .................................................................................................... 70
Lecture 10: applications of CO in Industry .............................................................................. 86
Lecture 11: Chemical catalysis, homogeneous catalysis....................................................... 102
Lecture 12: Heterogeneous Catalysis ................................................................................... 112
Lecture 13: N2 fication ......................................................................................................... 122
1
,Chemical Catalysis- JJ-2025
Lecture 1: Introduction, basic principle, refreshing
Catalysis applications
➢ Fine chemicals
o Manufactured in small, limited quantities by plants by batch process
o Example
▪ Chemical synthesis
▪ Biotechnology
▪ Extraction
▪ hydrolysis
➢ Bulk chemicals
o Made on a very large scale in continuous process in chemicals plants with
dedicated reactors to satisfy global markets
o Referred to as commodity chemical.
o Example
▪ Ammonia
▪ Sulfuric acid
▪ Sodium hydroxide
▪ Acetone
▪ Acrylic acid, bio
What is a catalyst and what it does.
A reaction may have a large, negative ∆Grxn, but the rate may be so slow that there is no evidence
of it occurring.
Thermodynamics Will a reaction occur?
Kinetics If so, how fast will the reaction occur?
Catalyst Substance that increases the rate of the
reaction without being altered, or consumed.
In practice, less than 1 eq. of catalyst is usually used
in the process
o However, sometimes it is more, but as long
as it increases the rate of the reaction it is
considered a catalyst
Does not change equilibrium position,
thermodynamics
Heat, stirring, sonication are not catalyst
should be able to propose a catalytic cycle, you don’t
necessarily have to remember.
2
,Chemical Catalysis- JJ-2025
What does a catalyst do?
➢ Stabilizes TS therefore lower activation energy.
➢ Enabling otherwise inaccessible reaction paths.
➢ Bringing reactants together: proximity effect, orientation effect
As a result
➢ Allow lower temperatures, using less aggressive reagents under milder conditions
➢ Higher yields and selectivity
➢ Allow to obtain enantioenriched chiral
product
Selectivity of chemical conversions
You can have 3 different products
But you want to obtain only one product
o Catalyst can be used for
selective formation of one
product
Catalysis is green
- Reduces the energy required
- Reduces the use of stoichiometric reagents
- Reduces by-products and waste
Problems
- Separation of catalyst residues from product
- Recycling of the catalyst
- Degradation of the catalyst
- Toxicity of the catalyst, the catalyst residues, and catalyst degradation products
Activity and productivity of catalysts
➢ Catalyst productivity: it specifies the total number of product P produced with a given
quantity of catalyst (under given reaction conditions).
o The figure is dimensionless, e.g. mol P/mol C, and described by TON: turn over
number.
▪ Another way to see is that moles product formed per mole catalyst
represents a catalyst stability measure.
▪ TON is an arbitrary number because it can vary depending on the time
allowed for the reaction to proceed and whether or not the catalyst
becomes inactive during the reaction.
➢ Catalyst activity: is measured as the amount of product formed per amount of catalyst
over given time interval (mol P/ mol C x time)by the turnover frequency TOF, of catalyst,
so it is the TON of the catalyst per unit time..
o Number of moles product per mole catalyst per unit time.
▪ A measure of catalyst efficiency
When TON and TOF are reported for a particular reaction the reaction conditions must be
specified, so that proper comparisons with other systems can be made.
3
, Chemical Catalysis- JJ-2025
4 is more active than 3, however you cannot say anything
about the TON.
➢ Catalysts 1 and 2 have comparable activity but
different productivity.
o Catalyst 2 is a subject of fast deactivation
➢ 4 is more active than 3, however you cannot say
anything about the TON.
o Catalysts 3 and 4 have respectively very
low and high activity. From the provided
time window, it is impossible to say much about the productivity since neither of
reactions has come to an end yet
(b)
Catalyst 2 has moderate activity and low productivity
Catalyst 3 has low activity but high productivity
Induction period for catalyst 4
3 main types of catalysis
➢ Homogeneous : Reagents and catalysts are all in the
same phase
o Organometallic catalysis: catalyst is a metal
complex
o Organocatalysis: catalyst is an organic molecule
➢ Heterogeneous: Reagents are in different phase from the catalyst
o Usually reagents are gas (or liquids) and are passed over a solid catalyst
o Lower activity
o Much more aggressive
o Easier to recycle
o Mechanistically also more difficult, due to the active sites of the catalyst
➢ Biocatalysis: Uses enzymes to catalyze a reaction
4
Chemical catalysis
Inhoud
Lecture 1: Introduction, basic principle, refreshing ...................................................................2
Lecture 2: Catalytic homogeneous hydrogenation/enantioselective catalysis .......................... 17
Lecture 3: Case study ............................................................................................................ 25
Lecture 4: Cross-couplings .................................................................................................... 27
Lecture 5: Cross-coupling --Part 2 Lecture 4 ....................................................................... 38
Lecture 6: Case study 2 ......................................................................................................... 47
Lecture 7: CH activation ........................................................................................................ 53
Lecture 8—part 2: Metathesis ................................................................................................ 60
Lecture 9: Organocatalysis .................................................................................................... 70
Lecture 10: applications of CO in Industry .............................................................................. 86
Lecture 11: Chemical catalysis, homogeneous catalysis....................................................... 102
Lecture 12: Heterogeneous Catalysis ................................................................................... 112
Lecture 13: N2 fication ......................................................................................................... 122
1
,Chemical Catalysis- JJ-2025
Lecture 1: Introduction, basic principle, refreshing
Catalysis applications
➢ Fine chemicals
o Manufactured in small, limited quantities by plants by batch process
o Example
▪ Chemical synthesis
▪ Biotechnology
▪ Extraction
▪ hydrolysis
➢ Bulk chemicals
o Made on a very large scale in continuous process in chemicals plants with
dedicated reactors to satisfy global markets
o Referred to as commodity chemical.
o Example
▪ Ammonia
▪ Sulfuric acid
▪ Sodium hydroxide
▪ Acetone
▪ Acrylic acid, bio
What is a catalyst and what it does.
A reaction may have a large, negative ∆Grxn, but the rate may be so slow that there is no evidence
of it occurring.
Thermodynamics Will a reaction occur?
Kinetics If so, how fast will the reaction occur?
Catalyst Substance that increases the rate of the
reaction without being altered, or consumed.
In practice, less than 1 eq. of catalyst is usually used
in the process
o However, sometimes it is more, but as long
as it increases the rate of the reaction it is
considered a catalyst
Does not change equilibrium position,
thermodynamics
Heat, stirring, sonication are not catalyst
should be able to propose a catalytic cycle, you don’t
necessarily have to remember.
2
,Chemical Catalysis- JJ-2025
What does a catalyst do?
➢ Stabilizes TS therefore lower activation energy.
➢ Enabling otherwise inaccessible reaction paths.
➢ Bringing reactants together: proximity effect, orientation effect
As a result
➢ Allow lower temperatures, using less aggressive reagents under milder conditions
➢ Higher yields and selectivity
➢ Allow to obtain enantioenriched chiral
product
Selectivity of chemical conversions
You can have 3 different products
But you want to obtain only one product
o Catalyst can be used for
selective formation of one
product
Catalysis is green
- Reduces the energy required
- Reduces the use of stoichiometric reagents
- Reduces by-products and waste
Problems
- Separation of catalyst residues from product
- Recycling of the catalyst
- Degradation of the catalyst
- Toxicity of the catalyst, the catalyst residues, and catalyst degradation products
Activity and productivity of catalysts
➢ Catalyst productivity: it specifies the total number of product P produced with a given
quantity of catalyst (under given reaction conditions).
o The figure is dimensionless, e.g. mol P/mol C, and described by TON: turn over
number.
▪ Another way to see is that moles product formed per mole catalyst
represents a catalyst stability measure.
▪ TON is an arbitrary number because it can vary depending on the time
allowed for the reaction to proceed and whether or not the catalyst
becomes inactive during the reaction.
➢ Catalyst activity: is measured as the amount of product formed per amount of catalyst
over given time interval (mol P/ mol C x time)by the turnover frequency TOF, of catalyst,
so it is the TON of the catalyst per unit time..
o Number of moles product per mole catalyst per unit time.
▪ A measure of catalyst efficiency
When TON and TOF are reported for a particular reaction the reaction conditions must be
specified, so that proper comparisons with other systems can be made.
3
, Chemical Catalysis- JJ-2025
4 is more active than 3, however you cannot say anything
about the TON.
➢ Catalysts 1 and 2 have comparable activity but
different productivity.
o Catalyst 2 is a subject of fast deactivation
➢ 4 is more active than 3, however you cannot say
anything about the TON.
o Catalysts 3 and 4 have respectively very
low and high activity. From the provided
time window, it is impossible to say much about the productivity since neither of
reactions has come to an end yet
(b)
Catalyst 2 has moderate activity and low productivity
Catalyst 3 has low activity but high productivity
Induction period for catalyst 4
3 main types of catalysis
➢ Homogeneous : Reagents and catalysts are all in the
same phase
o Organometallic catalysis: catalyst is a metal
complex
o Organocatalysis: catalyst is an organic molecule
➢ Heterogeneous: Reagents are in different phase from the catalyst
o Usually reagents are gas (or liquids) and are passed over a solid catalyst
o Lower activity
o Much more aggressive
o Easier to recycle
o Mechanistically also more difficult, due to the active sites of the catalyst
➢ Biocatalysis: Uses enzymes to catalyze a reaction
4
