David W.C. MacMillan: Nobel Prize lecture in chemistry 2021
Summary
TLDRDavid MacMillan's lecture delves into the world of asymmetric organocatalysis, a field he pioneered. He explains the significance of catalysis in daily life and industrial processes, the importance of asymmetry in molecular reactions, and the innovative approach of using organic molecules as catalysts. MacMillan's journey from his PhD to becoming a distinguished professor at Princeton is highlighted, along with the groundbreaking experiments and discoveries that have positioned organocatalysis as a key player in sustainable chemistry and its applications in creating perfumes, recyclable plastics, and life-saving medicines.
Takeaways
- 🎓 David MacMillan was born in Scotland in 1968 and obtained his PhD from the University of California, Irvine in 1996. He is now a distinguished professor at Princeton University.
- 🏆 MacMillan expresses gratitude to the Royal Swedish Academy of Sciences and the Nobel Committee in Chemistry, acknowledging the significance of the Nobel Prize and congratulating co-recipient Benjamin List and other laureates.
- 🔍 The script introduces the concept of 'asymmetric organocatalysis' by breaking down the term into 'catalysis', 'asymmetric', and 'organo', highlighting their importance in chemistry.
- ⛰️ Catalysis is described as a process that lowers the energy barrier for chemical reactions, making them easier, faster, and enabling new reactions to occur.
- 🌱 The impact of catalysis on the world is vast, including its crucial role in the production of food through the conversion of nitrogen to ammonia, which is essential for sustaining the global population.
- 🔄 Asymmetric catalysis is crucial in creating one mirror image of a compound over another, which is important in medicine where different mirror images can have different effects on the body.
- 🧪 The term 'organo' in catalysis refers to the use of organic molecules as catalysts, which are often inexpensive, safe, sustainable, and recyclable, contrasting with the use of metals.
- 💡 MacMillan's 'eureka' moment during his time at Harvard led to the development of the concept of organocatalysis, using organic molecules as catalysts instead of metals.
- 🌟 The success of organocatalysis is attributed to its ability to be a generic activation mode, applicable to a wide range of chemical reactions, not just one.
- 🌱 The script highlights the interdisciplinary nature of organocatalysis, merging with other fields such as photoredox catalysis to create sustainable chemical reactions powered by visible light.
- 🌐 Organocatalysis is presented as a democratizing force in catalysis, making it accessible and affordable for researchers worldwide, regardless of their country of origin.
Q & A
Who is David MacMillan and what is his current academic position?
-David MacMillan was born in 1968 in Bellshill, Scotland. He obtained his PhD in 1996 from the University of California, Irvine. He is currently the James McDonald Distinguished University Professor at Princeton University in the United States.
What notable award did David MacMillan receive in 2021?
-David MacMillan received the Nobel Prize in Chemistry in 2021.
What is asymmetric organocatalysis?
-Asymmetric organocatalysis is a type of catalysis that uses small organic molecules to accelerate chemical reactions while selectively producing one mirror image (enantiomer) of a molecule over the other.
Why is catalysis important in chemical reactions?
-Catalysis is important because it makes chemical reactions easier and faster by lowering the energy barrier required for the reactions to occur, allowing new chemical reactions to take place that otherwise might not happen spontaneously.
How does catalysis impact the global population?
-Catalysis impacts the global population by enabling the production of ammonia from nitrogen, which is essential for creating fertilizers that help sustain the food supply for the world's population. This catalytic reaction supports the nutrition of roughly 50% of the world's population.
What are the two major branches of asymmetric catalysis that existed before organocatalysis?
-The two major branches of asymmetric catalysis before organocatalysis were biocatalysis, which uses enzymes from living systems, and metal catalysis, which uses metals to produce one mirror image selectively.
What was David MacMillan's eureka moment related to organocatalysis?
-David MacMillan's eureka moment occurred when he realized that organic components of catalysts, specifically enamines, could be used to catalyze chemical reactions without the need for metals, leading to the development of organocatalysis.
What is the significance of the imidazolenones in MacMillan's research?
-Imidazolenones were significant in MacMillan's research because they were inexpensive, made from natural building blocks, and effective in catalyzing reactions to produce one enantiomer over the other, achieving over 90% enantiomeric excess.
How has organocatalysis impacted the production of perfumes and plastics?
-Organocatalysis has been used to produce perfumes such as Lily of the Valley and rose-smelling perfumes. It also plays a role in making plastics recyclable by breaking down polymers into monomers that can be reused, contributing to a more sustainable plastic economy.
What potential future applications does organocatalysis have?
-Future applications of organocatalysis include making pharmaceuticals, materials, and chemicals in a more sustainable and efficient manner. It is expected to play a significant role in creating sustainable technologies for an expanding global population.
Who are some of the key individuals and groups David MacMillan acknowledged in his lecture?
-David MacMillan acknowledged his PhD advisor Professor Larry Overman, his postdoctoral advisor Professor David Evans, his research groups at UC Irvine, Berkeley, Caltech, and Princeton, his wife Jean, his children, his mother-in-law Julie, and his siblings Ian and Lorraine. He also dedicated his talk to Carlos Barbas, a pioneer in organocatalysis, and his parents.
Outlines
🏆 Introduction and Asymmetric Organocatalysis
David MacMillan, born in 1968 in Scotland, is a distinguished professor at Princeton University. He expresses gratitude to the Royal Swedish Academy of Sciences and the Nobel Committee in Chemistry for the 2021 Nobel Prize, shared with Benjamin List. MacMillan reflects on the past two months and the common question he's been asked about asymmetric organocatalysis. He begins his lecture by defining 'catalysis' as a process that facilitates and accelerates chemical reactions, using the analogy of walking over a hill to illustrate the concept. He emphasizes the importance of catalysis in various aspects of life, including the production of food through the conversion of nitrogen to ammonia, a process essential for sustaining the global population. MacMillan also highlights the significant role of catalysis in industrial chemical reactions and the world's GDP.
🧪 The Significance of Asymmetry in Chemistry
MacMillan delves into the concept of 'asymmetric' by drawing an analogy with human hands and feet, which are mirror images but not superimposable. He explains that in organic chemistry, molecules can exist as mirror images that are distinct due to their non-superimposability. Differentiating between these mirror images, known as enantiomers, can be challenging and typically requires expensive equipment and time. However, the human sense of smell can discern these differences, as illustrated by MacMillan's daughter's ability to distinguish between two enantiomers by smell. This distinction is crucial in biology and medicine, as one enantiomer of a molecule can be beneficial while the other may be harmful or toxic. The pharmaceutical industry relies heavily on the ability to produce one enantiomer selectively, which is where asymmetric catalysis plays a vital role.
🔬 The Emergence of Organocatalysis
The term 'organo' is introduced by reflecting on the branches of asymmetric catalysis in 1996, which included biocatalysis and metal catalysis. MacMillan's journey in organocatalysis began during his PhD at UC Irvine under the mentorship of Professor Larry Overman and continued at Harvard with Professor David Evans, a pioneer in asymmetric catalysis. MacMillan's 'eureka' moment came when considering the use of organic molecules as catalysts, given their advantages over metal catalysts, such as being inexpensive, safe, sustainable, and recyclable. He moved to Berkeley as an assistant professor, inspired by advice from Professor Eric Herrera to focus on high-impact research. This led him to pursue organocatalysis, with the ambitious idea of developing a catalyst that could work for hundreds of different reactions.
🌟 The Breakthrough in Asymmetric Organocatalysis
MacMillan recounts the initial challenges and excitement in developing an organocatalyst that could selectively produce one enantiomer in the Diels-Alder reaction, a fundamental process in chemistry. The first attempt resulted in a 48% excess of one enantiomer, far from the 90% threshold needed for serious consideration by the chemistry community. After six nerve-wracking months, the team developed a new catalyst, imidazolenones, derived from phenylalanine and acetone, which successfully achieved the desired selectivity. This breakthrough was a significant step in establishing organocatalysis as a viable field, and MacMillan's first manuscript on the subject introduced the term 'organocatalysis' and the concept of a 'generic activation mode,' suggesting the potential for the catalyst to work across many reactions.
🔬 Advancing Organocatalysis and Photoredox Catalysis
Following the initial success, MacMillan and his team faced challenges in applying their organocatalyst to other reactions, leading to the development of a second-generation catalyst. This advancement significantly expanded the scope of organocatalysis. MacMillan acknowledges the contributions of other researchers in the field, emphasizing that organocatalysis was not the work of a single individual but a collective effort. He discusses the integration of organocatalysis with photoredox catalysis, harnessing visible light to drive chemical reactions, which has applications in creating sustainable technologies. The collaboration with postdoc Dave Nisevich led to the development of photoredox catalysis, which has since grown into a significant field.
🌿 Applications and Future of Organocatalysis
MacMillan explores the various applications of organocatalysis, including its use in creating fragrances and perfumes, developing recyclable plastics, and most notably, in the synthesis of pharmaceuticals. He highlights the democratizing effect of organocatalysis, making催化ysis accessible and affordable worldwide, thus enabling researchers from any country to contribute to the field. Looking to the future, he emphasizes the need for sustainable catalytic processes, including organocatalysis, biocatalysis, photocatalysis, and electrocatalysis, to meet the needs of a growing global population responsibly.
🙌 Personal Acknowledgments and Dedications
In the concluding part of the script, MacMillan expresses his gratitude to the people who have supported him throughout his journey. He thanks his wife Jean, his family, his mother-in-law Julie, his siblings Ian and Lorraine, and the educators who have influenced his life. He dedicates his talk to three individuals who have passed away: Carlos Barbas, a pioneer in organocatalysis; and his parents, who were always supportive and believed in his potential. MacMillan's heartfelt acknowledgments reflect the collaborative and personal nature of scientific discovery.
Mindmap
Keywords
💡Asymmetric Organocatalysis
💡Catalysis
💡Enantiomers
💡Organocatalysis
💡Diels-Alder Reaction
💡Imidazolenones
💡Enantioselectivity
💡Photoredox Catalysis
💡Catalytic Cascades
💡Sustainable Chemistry
Highlights
David MacMillan's introduction as the James S. McDonnell Distinguished University Professor at Princeton University.
MacMillan's gratitude towards the Royal Swedish Academy of Sciences and the Nobel Committee in Chemistry.
The explanation of what catalysis is and its importance in facilitating chemical reactions.
The significance of the Haber-Bosch process in converting nitrogen to ammonia for food production.
The impact of catalysis on 90% of industrial-scale chemical reactions and 35% of the world's GDP.
The concept of asymmetric catalysis and its relevance to the production of medicines.
MacMillan's personal journey from his PhD at UC Irvine to his influential work in asymmetric catalysis.
The introduction of organocatalysis as a novel approach using organic molecules as catalysts.
The development of the imidazolenone catalysts and their success in achieving high enantioselectivity.
The naming of the field of organocatalysis and its importance for the growth of the discipline.
The concept of a generic activation mode, suggesting the broad applicability of organocatalysis.
The evolution of organocatalysis into photocatalysis and its potential for sustainable chemical reactions.
The application of organocatalysis in the production of fragrances and perfumes.
The role of organocatalysis in creating recyclable plastics and contributing to a circular economy.
The use of organocatalysis in the development of pharmaceuticals, exemplified by the drug for chronic migraines.
The democratization of catalysis through organocatalysis, making it accessible worldwide for education and research.
MacMillan's reflections on the future of organocatalysis and its role in sustainable technologies.
A heartfelt dedication to the pioneers of organocatalysis, including Carlos Barbas, and MacMillan's family.
Transcripts
david macmillan was born in 1968 in
bell's hill scotland
he obtained his phd in 1996 from the
university of california irvine
he is currently the james mcdonald
distinguished university professor at
princeton university in the united
states
david mcmillan
i now welcome you on to the stage
we are very much looking forward to your
lecture
okay i'd like to begin by thanking the
royal swedish academy of sciences i'd
like to thank the nobel committee in
chemistry
i'd like to congratulate the other
co-recipient of this prize benjamin list
and all of the other 2021 nobel prize
winners
and i'd like to thank you all for your
attention this morning
the last two months has really been just
remarkable for me it's been an extremely
exciting time
and during that time i've been asked
many many questions but probably the
number one question i've been asked is
this one which is shown here what is
asymmetric organocatalysis
so i thought i'd begin my talk today by
breaking down each of these terms
the first term i want to tell you about
is catalysis what is catalysis
well catalysis is related to chemical
reactions
if you look around you right now
everything is made from a chemical
reaction in fact if i look in my office
and this is my desk every component
every material that's in my office is
made by a chemical reaction
now if we look at all those different
chemical reactions and we actually hone
in on one of them for example this one
shown here this is actually the chemical
reaction to make caffeine this is the
molecule which is found in your coffee
it turns out that all chemical reactions
require energy most chemical reactions
do not happen spontaneously
and to represent that most chemists use
what's called an energy diagram
now i'm not going to be so technical
here i just want to show you what this
energy diagram looks like and one aspect
i like about this is when i teach this
to undergraduates i always explain it in
the following way
imagine every night when you're going
home you actually have to walk over a
hill
to walk over a hill to get home would
obviously require a lot of energy every
single night
what catalysis does catalysis actually
lowers the barrier and in fact
introduces a tunnel to make it so much
easier for you to get home every night
and in the same way it does this for
chemical reactions it makes all chemical
reactions easier and faster so that's
exactly what catalysis is reactions are
easier faster and in many cases allows
new chemical reactions to take place
now you may ask yourself does catalysis
really impact the world
and it does and it does in many
different interesting ways but i thought
i'd just show you a few
so here's the first one this is the
population of our earth over the last
1000 years and you can see here it's
been pretty stable during that time
frame
till the beginning of the 20th century
and at that point you see this rapid
inflection
and at this moment it climbs up to eight
billion people on earth
now it turns out it would not have been
possible to have these eight billion
people on earth without this one
catalytic reaction which is shown here
this is the conversion of nitrogen over
to ammonia
now you may ask yourself well why do we
need ammonia
well we need ammonia to make food and we
would not have enough food on our planet
for those eight billion people without
this one catalytic reaction and in fact
if you think about your body right now
and you think about all the building
blocks that are in your body
50 of those building blocks contain
nitrogens that came from this one
catalytic reaction
now other ways that catalysis impacts
our world is that 90
of industrial-scale chemical reactions
at the present time actually use
catalysis and 35 of the world's gdp is
also based on catalysis
and this number is actually only going
to go up over the next couple of decades
as we move towards more and more
sustainable processes
now if you're wondering how does
catalysis impact your day-to-day life it
does so in many different ways we've
talked already about why we need it to
make food but also we need it to make
medicines we need it for solar cells we
need it for diagnostics even the global
manufacturing of polymers and materials
we need catalysis so clearly catalysis
is important for our world
so that's great that's catalysis but the
next part is what about asymmetric what
does asymmetric mean
well it turns out it's actually pretty
easy to describe what asymmetric means
to non-chemists because most people on
earth have two hands or you have two
feet and if you look at your two hands
we know that they're in fact mirror
images of each other
those mirror images are similar but
they're still different they're
different because they're not
superimposable which makes them
asymmetric
so how do we know that well we know that
for example if you were to take a
left-hand glove you know that it fits on
your left hand
but if you take that same glove and try
to put it on your right hand you know
that your right hand will not recognize
that glove it simply doesn't fit and
that's what you call it being
asymmetric now what's really interesting
in organic chemistry the same phenomenon
happens and these are two organic
molecules which are in fact mirror
images of each other but they're similar
but they're still different
which brings up an interesting question
in a lab how do you differentiate
between these two mirror image compounds
and it turns out that's not so easy in
fact it requires really expensive
instruments and requires a pretty long
period of time
what's really also interesting about
this however if you take these same two
mirror images and give them to most
humans in this case this is a
picture of my daughter emma when she was
three years old
it turns out even a three-year-old child
can take these two compounds and
differentiate them instantly just by
smelling them they can smell the
difference between these two compounds
now you may be wondering why is that
well that happens because biology human
biology is made up of building blocks
which are one mirror image but not the
other one
so for example proteins dna
carbohydrates hormones all these
building blocks of life are made up of
one mirror image but not the other one
now it turns out that has lots of really
important biological implications
the easiest one to sort of talk about is
with respect to medicine
because it turns out well your hands can
exist as mirror image it turns out many
medicines also it can exist as mirror
images and it turns out your body can
typically recognize one of those mirror
images but the other mirror image can
often be problematic it can be toxic it
can be dangerous
now this is a hundred billion dollar
market for our economy and as such it's
extremely important that we can have
access to one of these mirror images of
the medicine but not the other one
and the way you can think about going
about doing that would obviously be
through catalysis and this therefore
becomes known as asymmetric catalysis or
the desire to make one mirror image
selectively without making the other one
okay so that's asymmetric so the third
part of this is organo what does organo
mean
and to explain this i'm going to take
you all the way back to 1996.
why 1996 we'll talk about in a few
moments but we're actually first of all
going to discuss what were the branches
of asymmetric catalysis back in 1996 it
turns out there was two major branches
the first branch was biocatalysis
biocatalysis is when you take enzymes
from your body or living systems and you
use those to make one mirror image in
preference to the other one
the second major branch is metal
catalysis metal catalysis is a man-made
area which uses metals to allow you to
make one mirror image selectively
now if you're wondering why 1996 well
1996 is where my part in the story
actually begins
in 1996 i was finishing off my phd
studies at uc irvine out in california
now over the last two months many people
have said to me you must feel extremely
lucky extremely fortunate to have won a
nobel prize
and i tell them well i actually already
feel extremely lucky and fortunate
because i got to do my ph study phd
studies out in california at uc irvine
this was a really wonderful fantastic
time for me
and during that time i was also
extremely fortunate that i got to work
for this individual
this is professor larry overman he's
just a fantastic chemist he's an amazing
mentor but he's also really just a
superb human being
upon completing my phd studies i moved
back across america went to boston to to
harvard and i went to harvard to work
for professor david evans
david evans is a genius he's one of the
most influential chemists that's existed
and he's someone who is an absolute
master in the area of asymmetric
catalysis
and i moved to dave's lab to work in
this area and during that time i worked
on looking at metals to make single
mirror energy compounds
now these are some of the metals that
dave's group actually worked on and
during that time i learned an enormous
amount from dave and from his team but
every single day i was in dave's lab i
worked in this contraption this
contraption is known as a glove box this
glove box is designed to exclude air
it's designed to exclude oxygen it's
designed to exclude moisture
and every single day i would be in there
i'd be working away for many many hours
and after about two years of working in
a glove box i started to think to myself
why are we spending so much time in a
glove box every day
to understand that you have to think
about the metal catalyst themselves
so here is your typical metal catalyst
you can actually break it down into two
components the left hand side the right
hand side is shown here
the right hand side is the metal
if you think about these metals it turns
out metals in some cases but not in all
cases they can be expensive they can be
toxic they can be really difficult to
work with they often have problems being
out in the atmosphere which is why you
have to use glove boxes and in other
cases they're not sustainable
what's really interesting however if you
look at the other part of the catalyst
this is the organic component
organic molecules are often inexpensive
they're safe they're sustainable they're
recyclable
and at that time i started to think well
why don't we just simply use the organic
part as the catalyst and miss out using
the metal
now that was something that eventually
became known as organocatalysis
okay so in 1998 the end of my studies at
harvard i was really fortunate i landed
a job as an assistant professor at
berkeley
but before i got to berkeley i stopped
off at caltech to give a lecture and
while i was there i met with professor
eric
herrera and while i was there professor
carrera took me to dinner and gave me to
what is till this day one of the best
pieces of advice that anyone ever gave
me
he basically said the following
he said when you get to berkeley you're
going to be surrounded by some of the
best graduate students in the world and
you have to assume that whatever problem
you work on those students will help you
solve that problem regardless of whether
you have a solution to it already or not
and as such you should work on the one
which is of the highest impact you can
think of
so with this in mind i knew what i was
going to work on i was going to work on
organocatalysis
i knew that because of these advantages
we knew we could make them from nature's
building blocks we knew that these
molecules should not be sensitive to air
or moisture they should be inexpensive
these same types of catalysts should be
easy to handle you wouldn't have to use
a glove box because they can exist
happily out in our environment then
lastly they should be sustainable they
should be recyclable and they're
non-toxic
but this was not the main reason i was
interested in doing organo catalysis the
part that i was interested in was the
following idea
instead of trying to develop one or
catalyst organo catalyst that would work
for one transformation i was really
interested in the idea could we develop
an organo catalyst that could work for
hundreds of different reactions and
maybe this could become a field of
asymmetric catalysis
now that in and of itself was a pretty
grandiose idea the only problem is i had
absolutely no idea how to do it but
that's okay because eric carrera told me
it'd be fine i'd have great graduate
students they would help me solve this
problem
okay so in 1998 off i went to berkeley
started my research group and this is
one of my first photographs of that
group
i really love this photograph it's taken
at 10 past 10 on a friday night you can
see this young group in there doing
research trying to have an impact
and during that time one of the graduate
students in the group by the name of
tristan lambert tristan is now a very
successful professor over at cornell
university but back as a first year
graduate student he asked me a very
simple question
he said what is the mechanism of
reductive ammunition and i was a new
professor i was all excited to answer
this i ran to the board and i wrote well
we take a carbonyl you take an amine and
it reversibly forms an amino iron
and it's only when it's the amenia mine
does it have the electronic
configuration that it's reactive enough
to do the subsequent chemistry
and right there right then is when i had
my eureka moment
because i suddenly realized you could
use this idea for organocatalysis
more specifically you could take these
alphabet unsaturated carbonyls with the
means and reversibly form in many amines
and in many ways this should emulate a
field of catalysis and already been
successful using metals
now to sort of show this in a slightly
more conventional way if you think of
these two equations as shown in this
slide as being simultaneous the one on
the top is one that uses metals and it
turns out there's hundreds of reactions
that have been developed using that
concept
but the one at the bottom there was
basically no examples using organic
catalysts to do that but yet if these
were simultaneous equations they both
should be successful
and if that's the case then organo
catalyst should work for many different
types of transformations such as mukima
michael nitro and cycle additions the
less would go on and on and on of all
the possible reactions for
organocatalysis but at that time there
really weren't any
so we had to pick one of these one of
these we wanted to test it on
and what we chose was the diels-alder
reaction now the diels-alder reaction is
really famous to all chemists
it deservedly won the nobel prize in
1950 because it allowed you to take
relatively simple molecules and build
ring systems very much in a
straightforward fashion that could be
used in natural products that could be
used in medicines they could actually be
used in materials
we decided this reaction would be a
great platform or a great venue on which
to test our new organocatalysis concept
so we decided to use exactly that
so as shown here this is actually the
notebook page from kateria wren she was
a first year graduate student in my
group she was the first person in my
group to test this idea
and these are in fact the components of
a diels-alder reaction and you can see
in the middle above the arrow that would
be the organo catalyst
so we tested it we ran the reaction and
if we scroll all the way at the bottom
you'll see the result which is
highlighted it says not racemic
not racemic
that was unbelievably exciting to us not
receiving means it makes one mirror
image in preference to the other one
i was so excited when i saw this result
of an end to my office closed the door
jumped up and down for about five
minutes called my wife and said i think
we're going to get tenure we just got a
really really exciting result
but when my feet came back to ground i
walked back into the lab and i realized
that you can see the top of this slide
it says an initial result 48 ee
what does that mean well that meant in
terms of the meta remedies there was a
48 excess of one mirror image over the
other one
and for the chemistry community to take
this seriously that number actually has
to be about 90
so we had a decision to make did we want
to publish this or did we want to try
and go for a catalyst and go for the
gusto and get to 90
well we decided to do the latter and i
can tell you that was six of the most
nerve-wracking months of my life but
during that time we eventually got to a
catalyst that we thought was interesting
this is what's called the imidazolenones
we're interested in metazoans really for
two major reasons the first one was
they're really inexpensive
if you look at these molecules they're
actually made from phenylalanine which
is a building block of life it's an
amino acid that's combined with acetone
acetone is actually paint stripper
but the other reason we really liked
them we thought if we put these together
and made a catalyst they should be good
been able to generate the production of
one mirror image in preference to the
other one
and when we tested that that's exactly
what happened we could now achieve 90
percent excesses of one and the other in
these deals all the reactions
so again this was an extremely exciting
day in lab and at this point we're now
we have to tell the world
as a young professor you now have to
write a manuscript and you really want
to sort of climb up to the highest
rooftop and shout this out as much as
possible how important you think this is
and in fact when i look back on my first
manuscript i can see i really felt that
in this opening paragraph
in this opening paragraph i first of all
talk about why i think this is going to
have potential impacts on society for
academia for industry and for the
economy
the second thing i did in this holding
paragraph i gave this whole idea a name
i called it organocatalysis
now you might wonder organocatalysis why
does it matter you gave something a name
what's in a name
but it turns out naming things is really
really important for example you can go
back to john jacobs brazilians a very
famous swedish chemist very famous
scientist and while he was a
tremendously successful researcher he
was also the person that came up with so
much vocabulary and so much terms that
allow our field to have basically an
identity at the present time
words such as catalysis proteins polymer
even organic versus inorganic
and the importance of terms have carried
forward even into the modern era for
example things such as machine learning
nanotechnology organocatalysis these are
umbrella terms which really allow you to
describe fields that allow them to gel
and grow beneath those different types
of areas
but the third part of this opening
paragraph of the or manuscript which i'm
most proud of is that we introduced the
concept of a generic activation mode
now you may wonder what is a generic
activation mode but that's really just
the idea of saying that this idea of
catalysis should work not for one
reaction but for many many chemical
reactions
so obviously we had to go off and test
that
so if you remember we've just performed
the diels-alder reaction was shown here
so now we're ready to test it in other
reactions when we try it and it goes bam
bam
nothing it comes to a screeching halt
and this is something that happens in
science quite often where you get proof
of concept using one catalyst but you
suddenly realize it's not going to take
you all the different directions you
want to go in
so now we have to go off and design a
second generation catalyst
now with this in mind i was very
fortunate to have really two fantastic
young graduate students in my group by
the name of joel austin and chris barts
and what they did was they performed
molecular engineering on this first
catalyst they effectively took away two
carbons and then they introduced four
carbons in a different shape this was
sort of precision
engineering to try and describe this to
non-chemists that don't or to put it in
another context
one way i thought i could do this is to
talk about for example this footballing
god zlatan ibrahimovic who is someone
who is a precision footballer who does
precise things and achieves really
fantastic outcomes
one example of this is this goal he
scores where you can see here he does an
overhead kick
from almost 40 yards out to score this
goal
now okay he wasn't playing against a
team that was particularly good but the
point here is he performs a precision
technique to score a beautiful outcome a
really beautiful goal and we were
interested could we do the same with our
catalyst
so we set out to test this this was our
first generation catalyst we had three
reactions we now moved to a second
generation catalyst as shown here and
now we're off to the races things really
start taking off like gangbusters
at this stage we're also very fortunate
that carl anker jorgensen and hayashi
introduced another family of catalysts
which were also really valuable for
minimum catalysis and again completely
expanded this area
all right now at this point what we've
introduced is a minimum catalysis and
basically at the same time there was all
this beautiful work coming from ben
lester and carlos barbus really
expanding beautifully enemy catalysis
but i don't want to give you the
impression we were the only people who
were doing this in fact we certainly
weren't even the first ones to do it
there was many other people who were
sort of working in this area and i want
you to point those out
for phase transfer catalysis there was
doling ligo marioka and o'donnell in
lewis-base catalysis there was denmark
azeki and windberg in terms of
nucleophilic catalysis there was foo and
vedas in terms of peptide and partial
peptide synthesis was kelowna inuit
julia and miller
in carbine catalysis was ender's leaper
and tom rovas and in terms of hydrogen
bonding catalysis was corey and jacobson
and ketone catalysis there were sheet
and yang and one part i want to mention
which i think is absolutely critical if
it wasn't for the contributions of all
these people this field simply would not
exist and i certainly wouldn't be
standing here right now giving this
speech
okay so at this stage we started to
think about what other directions we
could take organo catalysis into
and one thing we thought of was wouldn't
it be interesting if you could take
imenium and enamine catalysis and put
them in the same vessel and you might
wonder why on earth would you want to do
that well it turns out we were
interested in emulating the way that
nature makes molecules it turns out what
nature does nature actually takes
enzymes in a biochemical assembly line
and in multiple catalytic reactions
takes simple molecules and makes very
complex ones
we started to ask could we do exactly
the same thing but instead of using
enzymes could we actually use small
organic molecules to do exactly the same
catalytic cascades
so in this context we took a relatively
simple molecule as the one shown in the
top left here and we put it through
these three catalytic cycles that all
sequentially fed into each other to
generate the molecule which is shown in
the bottom right hand side of the slide
now that molecule is much more complex
than the one in the top left and the
reason it's so much more complex is
we're trying to make the molecule shown
in this slide which is called strychnine
now you've probably heard of the word
strychnine before it's actually a very
dangerous molecule it's actually a
poison it's really a rat poison and you
may wonder why and if we're trying to
make rat poison
well it turns out this rat poison
stricken is actually a molecular
benchmark that people in the field of
total sentences use from which to
benchmark their technologies against and
using this cascade catalysis we were
able to in fact make it in a very rapid
12 steps
now other ways we started to think about
ways we could do exciting and new things
with organocatalysis was the idea could
be merged with other types of reactivity
the next type of reactivity we became
interested in was organic radicals
so this is moses gomberg he was the
person who discovered radicals in 1901
and has this really wonderful statement
in his manuscript which says this work
will be continued and i wish to reserve
the fuel for myself
well clearly that did not happen all of
the chemistry world started to use
radicals and the reason was because as
the name suggests radicals allow you to
do radical things they allow you to
achieve radical reactivity
and so we became really interested in
could you merge this with
organocatalysis
so this was actually work that was
conceived of and executed on by a really
fantastic graduate student in my group
by a name of theresa beeson
what teresa did was she said i should be
able to make these same enamines but
instead of using these enamines to do
chemistry what if we actually plucked an
electron out to change its reactivity
now that it's a radical this radical
should allow you to do many many
different new types of chemical
reactions and that turned out to be
exactly the case we published many new
types of processes using what's called
this somo catalysis
but this actually became a stepping
stone for us to think about could we
actually take radicals and
organocatalysis and make it even more
sustainable in terms of how you'd
actually perform these transformations
in this context we became really excited
about the fact of being able to sort of
harness visible light with
organocatalysis
now harnessing visible light is
something that inorganic chemists have
been working on for almost three decades
and the idea here was to try and harness
the the light that would come from the
sun and use that as energy to power the
planet
we became interested in the idea could
we take that knowledge that they had
developed but now transport it into the
organic world and once it was in the
organic world start to think about doing
a thing called photoreducts catalysis
this would allow us to make new bonds
this would allow us to perform new types
of transformations that could have a
whole variety of different applications
now it turns out this was actually work
that was performed in collaboration with
a wonderful postdoc in my group by the
name of dave nisevich
this is basically what we were
attempting is shown in this slide we're
taking light bulbs we're taking organo
catalysis and then at the right moment
we switch simply switch on the light we
switch on the blue led
and new chemistry starts to happen
now what's really exciting about photo
radars is that it became a field in and
of itself actually became a field as as
large as organocatalysis and that's
something that we're very much proud to
be a part of
now in terms of thinking about this the
part that's really exciting is we've
been really lucky as a group to be
involved with organocatalysis
and we've also been really lucky to be
involved with this field of photo radox
catalysis but it's been really exciting
to see that organocatalysis effectively
created this bridge at least in our lab
into photo radar catalysis in fact if
you think about it it really was a
catalyst that allowed for a redox
catalysis field to come together again
at least in our lab
okay so at this point another question
that a lot of people ask me what about
applications of organocatalysis and i'm
going to show you just a few
the first one is in the area of
fragrances perfumes
it turns out perfumes are used on an
enormous scale across the world every
single day
in pharmanish this company that's in
switzerland and geneva are very
successful at performing and producing
many of these different perfumes and one
of the ones which is actually shown here
is produced by combining organocatalysis
with photoreaders this actually makes
lily of the valley
tons of firminess also in northern india
make 300 metric tons of this beautiful
rose smelling perfume also using
organocatalysis
okay so that's perfumes what other areas
can use organocatalysis for well you can
actually use it in terms of materials
and actually for the recyclable plastic
economy this is some very important work
that's been conducted by bob weymouth
and james hedrick and many of you
probably know that plastics are
polluting our oceans
and what bob and james are doing is
they're using organocatalysis to
effectively break down polymers back
down to monomers which can then be used
again to remake polymers making polymers
and plastics completely recyclable and
completely sustainable which is
obviously extremely important
but the area in which organocatalysis is
probably most heavily used is that
towards making medicines or developing
medicines
i'm just going to show you one example
this is tulsa japan it's actually used
to treat chronic migraines
this particular molecule this particular
medicine is actually made and it's made
using organocatalysis and in fact it
uses the immune catalysis i talked about
the beginning of my talk to make one of
the mirror images in preference to the
other one
but the last thing i want to talk about
with respect to the value of
organocatalysis is this slide which is
shown here we call this democratizing
catalysis now this is an aspect of
organic catalysis i certainly did not
see coming but i think it may be one of
the most important aspects of
organocatalysis
and it is that organic catalysis is
extremely affordable and a cheap and
accessible feel to the whole world
and this means if you go across every
continent that exists in the world right
now people are being educated about
organocatalysis using these different
systems
they're so inexpensive to the point that
it's really straightforward for people
not just to learn about using them but
actually to do their own research
so when i think about where the next big
idea in organo catalysis is going to
come from
i realize it's not going to be about
resources it's not going to be about
funding
it's going about who in the world has
the best idea regardless of which
country they come from
okay now people often ask me what does
the future hold for organocatalysis and
to be honest with you i really don't
have an answer to that question
but what i do know is that we have to
provide for our ever expanding global
population in a responsible way and that
includes catalysis catalysis has to be
sustainable as we go forward
so clearly this will involve using
organocatalysis and biocatalysis will
also include things like photocatalysis
and electrocatalysis it's going to be
essential that we move to these types of
catalysis if we're going to create
sustainable technologies for our planet
okay so that's my last chemistry slide i
want to finish off by thanking the
people who first of all did this work i
talked about the people already from
berkeley we moved to caltech where we
actually did most of organo catalysis
research and i want to thank all the
people who are sort of shown on this
slide here this was a fantastic group to
work with and i also want to thank also
all my friends and the faculty members
out at caltech
in 2006 we actually moved over to
princeton we continued our organic
catalysis work and also we started doing
lots of photo redox as well and again i
have to thank these phenomenal groups
these phenomenal teams i was lucky to
work with during that time frame
in terms of other people i have to thank
i have to thank this woman this is my
wife jean she's a love of my life she is
an amazing person she's an amazing
chemist she's an amazing mother but more
than anything she's my best friend and
this journey honestly would not have
been the same without her being there so
i have to thank her so much
i also have to thank my family this is
danielle this is lauren this is emma
this is us having a boogie on the
harbour bridge in sydney which was a lot
of fun that day and i also have to thank
julie julie is my unique and wonderful
mother-in-law who's been an amazing
supporter through all of our times as we
went all through all these different
stages of our life
in terms of other people i have to thank
i have to thank my siblings ian and
lorraine
many people have heard this story that i
would not have went to university if it
wasn't for my brother going there first
but i think people haven't heard the
story that i wouldn't have survived the
university if it wasn't for my sister
lorraine so i just want to say them i
love you both and i can't wait to
celebrate with both of you
other people i have to thank have to
thank educators that basically first of
all the educators all over scotland who
work very tirelessly to take people like
me and try to put them in a better spot
i have to thank the teachers at the
stevenson primary bestseller academy and
i have to thank the faculty and staff at
the university of glasgow and again
without these people i certainly
wouldn't be standing on this stage
the last part um is i want to dedicate
this talk and i want to dedicate this
talk to three people who are not here
the the first person i want to dedicate
this to i've already mentioned and
that's carlos barbus
carlos was a pioneer of organocatalysis
he was right there at the beginning with
myself and ben
unfortunately he was taken away from us
too early in
2014 and over the last two months i
think about carlos every single day
and it would have been so wonderful if
carlos had been here to celebrate this
with both myself and ben
the last people i want to dedicate this
to are my mom and dad um
this is a very difficult thing for me
but basically someone recently said to
me how would your mom and dad felt about
this would they have been proud would
they be proud of you winning this prize
and i said that i don't have the words i
can't articulate
how how proud they would be i just can't
get there
but the one thing i can tell you is a
seven-year-old boy in scotland there's
no way i could imagine i'd be standing
on this stage giving this speech but i
think my mom and dad could have because
they were unbelievably supportive and
they believed that myself and my family
we could go absolutely anywhere and for
that i'm incredibly grateful
with that i want to thank you for your
attention thanks a lot
you
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