White Phosphorus Is Air-Stable Within a Self-Assembled Tetrahedral Capsule
Prasenjit Mal,1
Boris Breiner,1
Kari Rissanen,2
Jonathan R. Nitschke1,*
The air-sensitive nature of white phosphorus underlies its destructive
effect as a munition: Tetrahedral P
4 molecules readily react
with atmospheric dioxygen, leading this form of the element
to spontaneously combust upon exposure to air. Here, we show
that hydrophobic P
4 molecules are rendered air-stable and water-soluble
within the hydrophobic hollows of self-assembled tetrahedral
container molecules, which form in water from simple organic
subcomponents and iron(II) ions. This stabilization is not achieved
through hermetic exclusion of O
2 but rather by constriction
of individual P
4 molecules; the addition of oxygen atoms to
P
4 would result in the formation of oxidized species too large
for their containers. The phosphorus can be released in controlled
fashion without disrupting the cage by adding the competing
guest benzene.
2 Department of Chemistry, Nanoscience Center, University of Jyväskylä, Post Office Box 35, 40014 JYU, Finland.
* To whom correspondence should be addressed. E-mail: jrn34{at}cam.ac.uk
