Chemistry Nobel prize goes to pioneering research into palladium-catalysed cross coupling, now ubiquitous in organic synthesis
The 2010 Nobel prize for chemistry has been awarded to three pioneers of synthetic organic chemistry whose eponymous reactions have become ubiquitous and indispensible.
Richard Heck of the University of Delaware in Newark, US, Ei-ichi Negishi of Purdue University, US, and Akira Suzuki of Hokkaido University in Japan, independently developed palladium-catalysed cross-coupling reactions as a way to forge new carbon-carbon bonds with precision and under mild reaction conditions. Heck, Negishi and Suzuki reactions are now used universally in every organic synthesis laboratory across the world, as well as in major industrial processes.
The three chemists have been working in the field for decades, and if there is one surprise about their being awarded the prize, it is perhaps that it didn’t come sooner.
Heck published a series of papers in 1968 reporting the addition of methyl and phenylpalladium halides to olefins at room temperature. A further step allowed the unprecedented alkylation of an olefin. In 1976 Negishi investigated the palladium-catalysed cross-coupling of organometallic species with organohalides, eventually demonstrating that organozinc compounds could permit highly selective reactions under mild conditions and in the presence of a range of functional groups. Suzuki focused on organoboron compounds, demonstrating in 1979 that such species in the presence of a base could be cross coupled with vinyl and aryl halides in the presence of a palladium catalyst.
In subsequent years these reactions were improved and modified to become indispensible tools for the organic chemist and have been used to synthesise a range of complex natural products which would otherwise remain extremely difficult if not impossible to make.
Speaking from his home in the US at 6am, having been awoken an hour earlier with news of the prize, Negishi pronounced himself ’extremely happy - this means a lot.’ He conceded that he knew the award of the Nobel Prize was a possibility, and indeed had been a long-held ambition. ’There had been some mumblings and I did begin to think of this and that,’ he laughed. ’I have been dreaming about this prize for half a century, since I came to America and encountered several Nobel laureates, when I realised it was not a story - it was a reality which in principle could happen to anyone, including myself.’
Negishi added, ’I have accomplished half my goal. I would like to keep working for at least several more years.’
Guy Lloyd-Jones, a synthetic organic chemist at the University of Bristol in the UK, says that the trio are ’extremely worthy’ winners. ’It is hard now to pick up an issue of any mainstream chemistry journal that features organic synthesis which does not contain a number of papers in which these reactions have been used. These reactions have revolutionised our ability to make selective carbon-carbon bonds. The prize is absolutely deserved and the only question that some people have asked is why it has taken so long.’