As a former chemist, I sometimes feel sad that straightforward chemistry does not get the media coverage it deserves. A really elegant piece of chemistry research, carried out at Cambridge University, was published in Science today. It got disappointingly little attention in newspapers and on science websites. (Even the FT cut out my mention of the experiment in the newspaper’s science briefing column, for lack of space.)
The Cambridge chemists have “tamed” white phosphorous, one of the most hazardous substances used as a common chemical feedstock. White phosphorous – an ingredient in weedkillers, insecticides and fertilisers – is liable to burst into flames when it comes into contact with air. It is also a controversial weapon.
White phosphorous is a tetrahedral molecule of four phosphorous atoms. The Cambridge researchers made a molecular cage of carbon, hydrogen, iron, nitrogen, sulphur and iron atoms. This can hold the four phosphorous atoms indefinitely and prevent them reacting with atmospheric oxygen. The phosphorous is released from its cage when needed, simply by adding benzene.
The caging technique could be used to make industrial handing and storage of white phosphorous safer. In addition, says Jonathan Nitschke, project leader, “it is foreseeable that our technique might be used to clean up a white phosphorous spill, either as part of an industrial accident or in a war zone. In addition to its ability to inflict grievous harm while burning, white phosphorous is very toxic and poses a major environmental hazard.”
(Molecular model showing the four white phosphorous atoms inside their cage, courtesy of Science.)