CL-20, a high-energy material with a cage-like structure, is
considered the most powerful explosive today. It is usually
prepared via nitration with concentrated nitric and sulfuric
acid, but this technique pollutes the environment. In this
article, CL-20 was synthesized by nitration of 2,6,8,12-
tetraacetyl 2,4,6,8,10,12-hexaazatetracyclo[5,5,0,03,11,05,9]
dodecane (TAIW) using a clean nitrating agent, heteropolyacids.
Using the new nitrating agent caused the elimination
of concentrated sulfuric acid during the reaction.
This is an environmentally friendly technique.
