Gas-phase hydrogen/deuterium exchange reactions on hydrogen-bonded ions yield quite detailed information on mechanistic and structural aspects of isolated supramolecules. It has been utilized to provide evidence for the intramolecular mobility of crown ethers within oligolysin/crown-6 and POPAM dendrimer/crown-6 complexes and thus highlights the surprisingly pronounced dynamics within such complexes.
Furthermore, a concerted H/D-exchange mechanism operating in dimeric resorcinarene capsules could be detected which resembles a one-dimensional variant of the well-known Grotthus mechanism for proton transport in water.
These H/D-exhcange experiments finally resulted in the observation that large crowns (e.g. crown-8 and beyond) catalytically drive the ammonia elimination reaction of primary amines by simultaneously enhancing the leaving group capability of the ammonia molecule and offering a base for the proton at C(2).
Mercator projection of the hydrogen bonding seam of a dimeric resorcinarene capsule and concerted H/D-exchange reaction with methanol-OD