Interview with Jean-Pierre Sauvage on 6 December 2016, during the Nobel Week in Stockholm, Sweden.
Jean-Pierre Sauvage, welcome to the Nobel Week in Stockholm.
Jean-Pierre Sauvage: Thank you.
All Nobel Laureates are asked to bring an artefact to donate to the Nobel Museum here in Stockholm, what did you bring?
Jean-Pierre Sauvage: I brought some documents; shall I show you the documents?
Jean-Pierre Sauvage: There was a tradition in my group, which was, at the beginning of the year, of the academic year in October, to have a long, long discussion about the research projects we were going to tackle in the coming year. And also, about the research projects which were started before and continued, to know how everything was working. I was in charge of this type of seminar and so it says here ‘research project’, I mean it’s a document in French; Présentation de projets de recherche. I’m pretty sure you can understand, and it was written on October 7, 1982. So, this is the authentic document, even written on scratch paper, you see the back of the sheet.
So, what’s in it, what’s the content of the document?
Jean-Pierre Sauvage: The content is simply the various projects we were going to start at that time. And in 1982, interlocking molecules, like that, were basically unknown. And I think one of the main points is that … so they appear in this document. And there’s already a strategy for making them, a strategy for making an even slightly more complex ‘catenane’. I believe this is my first written document on catenanes. October 1982, so nothing was published ‘til one year later. And this is the paper which kind of represents what happens between the project and what was achieved. It’s a publication which appeared in 1983 in Tetrahedron Letters. If I may add just one thing, it has something very special; I have published hundreds and hundreds of papers, but there are very, very few papers published in French; written in French. And this one is written in French. It says, if I translate, “a new family of molecules, metal containing catenanes”.
Why is it written in French?
Jean-Pierre Sauvage: It was written in French because we didn’t know whether it would be exceedingly important. But we knew that the idea was novel. And the strategy was kind of revolutionary in a way. And we knew it was novel, and so we thought we do not take much risk if we write the paper in French. The people interested in this type of molecule will have to read it anyway, and it’s kind of a message that you can also consider that there are other languages than English.
So it was kind of a statement?
Jean-Pierre Sauvage: Yes, kind of a statement, I mean it as a bit provocative also, but at that time, you know, I used not to be very serious.
So, if I understand right, it took over one year for you to actually succeed with your experiments?
Jean-Pierre Sauvage: Not for me. For the lady who was doing the work, Mrs Dietrich-Buchecker, it’s a German name because she was from Strasbourg, and she was an incredibly skilful organic chemist. She could materialize the project, convert it to a publication, to some real resource. So, I would take this opportunity to thank her, to pay homage to her qualities.
How long had you been into research in 1982?
Jean-Pierre Sauvage: I started my PhD thesis in 1968. A good year in France; the students’ revolution, and I was among them. And in ’68, although the surrounding was very special, I mean there were lots of things happening. I was working pretty hard, with another friend who was a PhD student with Lehn, and together we made the first ‘cage like’ molecules, cryptands, cryptates, and that was published in 1969. It was my PhD thesis work. And Jean-Marie Lehn won the Nobel Prize in 1987. To a large extent in relation to this first piece of work, but of course he expanded the field spectacularly.
What brought you to science in the first place?
Jean-Pierre Sauvage: In the first place, you know when you are a kid, you try to do what you like. I was good in math, mathematics was kind of my favourite topic, and that was it. And then I was interested in physics and chemistry, but I preferred math.
So it was a natural choice for you?
Jean-Pierre Sauvage: It was kind of a natural choice, yes.
And how come you started, you got interested in just chemistry, and maybe even photochemistry?
Jean-Pierre Sauvage: Yes, chemistry, I always preferred chemistry versus physics
Jean-Pierre Sauvage: I don’t know, I used to do experiments. You know when I was sixteen, seventeen years old, distillation, separating chlorophylls from plants, things like that.
Was this in school you made these experiments?
Jean-Pierre Sauvage: No, that was at home. I liked that, it was not very serious, but I liked to do experiments. And physics was ok, but it was not my favourite topic.
Do you remember the moment, or the environment where you actually got the idea that led to this discovery?
Jean-Pierre Sauvage: Yes, sure. I think you know in some of the recommendations of the Nobel Foundation for the Nobel Lecture, they suggest you to explain frankly, honestly, how you came up with the idea. And that’s what I’ll try to do. I remember very precisely. It was coming from photochemistry; you know we were photochemists.
That’s chemistry that’s triggered by light?
Jean-Pierre Sauvage: By light, exactly; chemistry or electron transfer or very much related to photosynthesis. Photosynthesis is very important in nature, and I think the dream of many chemists is to do artificial photosynthesis; to convert light energy to chemical energy.
Was that your dream to?
Jean-Pierre Sauvage: That was my dream for many, many years. And doing that, we had an idea, which was pretty simple, which was to use one of the molecules we were working on, photoactive species, and to make a catenane out of it. And it seemed to be very, very easy.
And the catenane that you mentioned, if you hold it like that and show me. What is this?
Jean-Pierre Sauvage: It’s moving. This is the very first catenane we made, which is reported in this publication. The drawings are certainly very naïve in here; they were hand-made. And this is the first catenane we made in 1983.
And it’s a totally new type of chemical bond, if I understand it right?
Jean-Pierre Sauvage: It’s a new type of chemical bond, yes, Fraser Stoddart calls it the mechanical bond. And we have been more, let’s say, topology oriented, so we say that it is a topologically non-trivial molecule, or topologically non-planar molecule. This is how topologists in mathematics would refer to this molecule; non-planar. Non-planar meaning that you cannot hold any sheet of paper in a two-dimensional space without crossings; you have to have crossings. And it’s clear here you have two crossings.
And how does this discovery take us to the chemical machines?
Jean-Pierre Sauvage: That’s a very good point. It’s very close, in a way, because if you have things like that, you know two interlocking rings, or a ring threaded by an axis, you can relatively easyly figure out that a ring can glide; rotate within the other ring, or the ring threaded by an axis can move along the axis on which it has been threaded, from a position to another position. And this is the beginning of molecular machines.
So, the movement?
Jean-Pierre Sauvage: The movement, the controlled movement, you have to be able to trigger the motion.
And how is the motion triggered?
Jean-Pierre Sauvage: In our case it is triggered by an electro-chemical signal. Not in this particular molecule, but in a molecule which is very similar. And you can abstract an electron or re-inject an electron, in a molecule. And each time you do that, you set the molecule in motion, you trigger the motion.
Did you have any idea of what the molecule could be used for?
Jean-Pierre Sauvage: Yes, sure. We and others, again Fraser Stoddart, Ben Feringa and nowadays, many other people. I think the work of Fraser Stoddart in particular, and his group, is really spectacular. Very much in relation to molecular computing, you know storage of information, processing of information, and using molecules.
In what timespan do you think we will have the molecular computing?
Jean-Pierre Sauvage: It is too risky to say, I am not going to bet on that.
How many failures were there before you got the right chemical reaction to achieve this?
Jean-Pierre Sauvage: The first molecule was relatively easy to make, again thanks to Christiane Dietrich-Buchecker, she was a fantastic organic chemist.
So, you yourself didn’t fail a lot?
Jean-Pierre Sauvage: No.
Was it very, has it been very hard work for you in a laboratory?
Jean-Pierre Sauvage: No, not at all. The idea was good in a way, and the synthetic strategy was good, also thanks to her, I insist on that. The work, in chemistry, the work done by the people, it’s a team work. Each time you have a team of people, working together, and everybody has a function, as a contribution, and her contribution was very important.
So, you were in the same team as her?
Jean-Pierre Sauvage: Yes.
What’s important, what different kinds of persons do you need in a team in chemistry to make these big achievements?
Jean-Pierre Sauvage: I think the first characteristic is to work with people you get along well with. Preferably with friends. She was a very good friend of mine. And I think the same holds true for the students and the postdocs, you have to have very good relations. And the second point is to have people with various backgrounds also. If everybody has the same expertise in the same field, in a way, it’s not going to be very rich in terms of discussions in group meetings, at coffee, or whenever. But if the people have various backgrounds, I mean, it’s very enriching.
Do you mean mostly scientific background?
Jean-Pierre Sauvage: Scientific background yes.
And cultural too?
Jean-Pierre Sauvage: And cultural too, of course. It adds to the quality of the communication.
And how would you describe yourself, your type, who are you in this team?
Jean-Pierre Sauvage: I think I’m an easy to interact with person. And I like friendly relations, to me it is absolutely essential.
What is needed to get this far? I mean to be rewarded the Nobel Prize?
Jean-Pierre Sauvage: I think you have to be motivated. The first thing is not to think of the Nobel Prize. Not to think of any prize.
Have you never done that? During your years as a scientist?
Jean-Pierre Sauvage: Some people told me, maybe, you know, you could be on a list or whatever. Each time I was just laughing and telling them: “don’t be silly”.
What’s needed more than not thinking of the prize?
Jean-Pierre Sauvage: I think you have to be motivated. There are several things: you have to love science, you have to love the idea of making discoveries. And the second thing is you have to pay attention, to be very, very careful to potential research projects you may think of. Every day, every hour. And you have to take any opportunity. When you discuss with your group, when you start a new project, you may have another idea leading you to a different topic. You shouldn’t be scared. You should jump, you know. You shouldn’t ask yourself the question: “Will I be able, will I be good enough to do that?” You have to test yourself. You do it, if it fails, it fails.
But did you ever have hard times and thinking of just giving up and do something else?
Jean-Pierre Sauvage: Yes, sure, several times.
What happened then?
Jean-Pierre Sauvage: Several projects didn’t lead to anything.
But you never gave up?
Jean-Pierre Sauvage: No. Well, some projects, we gave up. But if you have ten projects at the same time, then if one or two projects fail, it’s not the end of the world.
But you never thought of leaving science?
Jean-Pierre Sauvage: No, never. No, never, this is my life.
We’ve talked a lot about your research and your career, but what else in life is important for you?
Jean-Pierre Sauvage: My family. I get along very well with my wife.
Is she a scientist too?
Jean-Pierre Sauvage: No, she’s a philosopher. Since the first time we met, more than forty-five years ago. And my son, and also friends are very important, to have good friends, to exchange with them. I love gardening.
Jean-Pierre Sauvage: Yes, I love …
Do you have a big garden yourself?
Jean-Pierre Sauvage: No, we have a very small garden in Strasbourg, but we have a second house on the Mediterranean, in the south of France, with a nice garden. So, I do a bit of gardening.
And do you still hope that you will construct artificial photosynthesis, so your flowers can grow even better?
Jean-Pierre Sauvage: Yes, artificial photosynthesis is a bit ambitious, because you know the … What I hope is that we can convert light energy into chemical energy; make a fuel from light and water and CO2. Artificial photosynthesis in this way could be realistic. But photosynthesis, it’s much more than that.
Do you have time to spend with your friends and family, or is almost all your time devoted to science?
Jean-Pierre Sauvage: No, I think I have never been completely focused, and only focused on science. I had vacation with my family every year.
Do you think that is important, to get a lot of other influences?
Jean-Pierre Sauvage: Sure. If you want to have a balanced life, you know, sure you have to.
Are you creative also on your time off from science?
Jean-Pierre Sauvage: Creative I don’t know, but I think of science, sure.
So, thank you very much for the interview and I hope you enjoy your stay in Stockholm now for the rest of the week.
Jean-Pierre Sauvage: Thank you. The interview was a great pleasure, I thank you.
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Their work and discoveries range from the Earth’s climate and our sense of touch to efforts to safeguard freedom of expression.
See them all presented here.