Sound approach to unclicking click chemistry

US chemists have attached polymer chains to a small, robust molecule and used ultrasound to grab the chains and literally pull the molecule apart. The technique can reverse click chemistry reactions, a popular transformation in which simple starting materials are snapped together under mild conditions. Reversing this process, or 'unclicking' the components, could be used to activate covalent bonds in a manner that is inaccessible through thermal or photochemical treatments.  More...

http://www.rsc.org/chemistryworld/News/2011/September/15091104.asp