Wolf Prize Laureate in Chemistry 2018
Affiliation at the time of the award:
University of Tokyo, Japan
“for his achievements in the field of supramolecular chemistry”.
Traditional chemistry has focused on intermolecular connections, particularly on strong covalent bonds formed when two atoms share one or more electrons. In contrast, supramolecular chemistry deals with the study of connections and interactions between molecules – a study that promotes the development of novel materials with unique properties that are sometimes very useful.
Makoto Fujita, born in 1957, developed his academic career quickly and at the age of 42 was appointed full professor at Nagoya University. Three years later (2002) he was appointed to the same position at Tokyo University, the most prestigious university in Japan. He was soon recognized as one of the pioneers in the field of supramolecular chemistry and was awarded many prizes: the Arthur C. Cope Scholar Award from the American Society of Chemistry, the Izatt-Christensen International Award for Macrocyclic Chemistry, the International Society for Nanoscale Science, Computation, and Engineering (ISNSCE) Award, The Fred Basolo Medal for Outstanding Research in Inorganic Chemistry from North Western University and the Nagoya silver medal. Fujita’s impressive academic yield, since the beginning of his academic career till today (i.e., between 1980 and 2017), includes approximately 330 publications.
Makoto Fujita’s main contribution to Supramolecular Chemistry has been the development of a new method for the formation of supramolecular structures called “metal-guided synthesis” or “self-assembly with metallic guidance”. This novel method enables quick and spontaneous assembly (under specific thermodynamic conditions) of supramolecular materials, and is much easier and more effective than the cumbersome, tedious, and highly inefficient methods previously used to synthesize such materials. As early as 1990, Fujita published an article describing this method of synthesizing materials on a nanometric scale containing both metal ions and various organic molecules (i.e., molecules containing carbon and hydrogen atoms connected to each other). Fujita and his colleagues used this method to synthesize a molecular square at each of the four vertices in which the metal atom Palladium, Pd (H is hydrogen, N nitrogen and O oxygen.
In the years that followed, this method was used to build increasingly complex molecules, nanostructures and materials. Fujita’s group, for example, synthesized three-dimensional porous molecules, called “cages”, that can be used as molecular “containers” that store smaller molecules. This structure may give the trapped materials new chemical properties: for instance, it may increase the solubility of drugs and therefore their effectiveness.
Several years ago, Fujita and his colleagues managed to synthesize a cage large enough to store protein molecules in its pores. This is of great practical importance, since many new drugs are protein-based. In 2016, they succeeded in assembling relatively large cage, 8 nanometres wide, (a nanometre is one billionth of a meter), and later that year they theoretically proved that, with the self-assembly method they had developed, it is possible to assemble 144 such cages into one stable, giant cage. Another acceptable use of materials, synthesized by the self-assembly method, is catalysts that accelerate chemical reactions that, in their absence, occur very slowly.
A particularly important and interesting application of these large cages, developed by Fujita himself, is the possibility of using them for x-ray crystallography (for studying the crystalline structure of matter) without even having to produce a crystal of the material being tested. Instead of this, the material can be “imprisoned”, in a synthesized cage that positions and stabilizes it in such a way that it can be directly examined using standard crystallography.