Direct analysis in real time mass spectrometry of fused ring heterocyclic organometallic compounds

Direct analysis in real time (DART) was able to desorb/ionize a series of fused-ring heterocyclic organometallic compounds to allow molecular analysis using a linear ion-trap mass spectrometer. Limited data is available pertaining to the use of ambient ionization with organometallic compounds but the developed analytical method allowed direct sampling of solutions prepared from pure organometallic compounds in dichloromethane to generate signals in the positive mode. A protonated molecule was detected (even when a charged ring structure was present) but signal intensity was dependent on the organometallic compound with respect to the specific metal-ligand interaction of the molecule as well as the helium gas temperature in the DART ion source. In addition, dimer formation for compounds was also observed. Tandem mass spectrometry was also possible to verify the tricarbonyl groups from the organometallic compound and show relative differences with respect to metal coordination. The desorption/ionization of these heterocyclic organometallic compounds with DART potentially gives synthetic chemists another ionization choice for rapid reaction product monitoring.