Characterization of organometallic coordinative cluster compounds of silver by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was successfully applied to characterize the organosilver coordinative cluster compounds, silver phenylacetylide and three silver thiolates, namely, silver tertiary butylthiolate, silver 2,6-dimethylbenzenethiolate, and silver 2,6-dichlorobenzenethiolate. Samples and dithranol matrix were finely dispersed in 1:1 tetrahydrofuran (THF)/chloroform (CHCl3) mixed solvent. In most cases the monomer units remained intact during ionization, and the oligomeric molecular ions were produced through silver cationization, with a general molecular ion formula [nM + Ag](+), This was further verified by the relative abundances of the isotopic peaks within the molecular ion clusters, which were in close agreement with those theoretically calculated for nM cationized with one silver ion. In the case of silver 2,6-dichlorobenzenethiolate, in addition to the dominant [nM + Ag](+) peaks, weak peaks corresponding to the successive losses of hydrogen chloride molecules were observed. Copyright (C) 2000 John Wiley & Sons, Ltd.