Electron impact and chemical ionisation mass spectrometry in the characterisation of organometallic silicon, germanium, tin and lead compounds

Abstract

The electron impact and chemical ionisation mass spectra of a number of organometallic derivatives of silicon, germanium, tin and lead, incorporating inter alia 2-bis(trimethylsilyl)methylpyridyl or cyclopentadienyl ligands have been recorded. Representative spectra are presented and illustrate the utility of these mass spectrometric techniques in the characterisation of such compounds, particularly so in light of the highly informative nature arising from their fragmentation patterns and the numerous isotopes of the nuclei involved. Copyright 2000 John Wiley & Sons, Ltd.

Structural analysis of organometallic compounds with soft ionization mass spectrometry

“…The presence of other metalloid (Weinmann et al, 1999), maingroup metal (Beckmann et al, 1998;Constantine, Cardin, & Bollen, 2000;Schumann et al, 2006), transition-metal (Ruiz et al, 1999;Arevalo et al, 2001;Wong, Wong, & Lu, 2003;Jain, Lalancette, & Sheridan, 2005), or lanthanoids (Al-Juaid et al, 1999) is typical for silicon organometallics. Complexes of lowmolecular weights were mostly measured with EI MS (Al-Juaid et al, 1999;Weinmann et al, 1999;Constantine, Cardin, & Bollen, 2000), whereas the method of choice to measure polymers and dendrimers is MALDI-TOF. The observation of monocharged molecular adducts with a high-resolution isotopic pattern and a minimum of fragment ions establishes the chemical formula of different species, determines the abundance of all components, and the molecular weights and the mean ring size or chain length of samples (Kohler, Schell, & Weber, 2002) as for FIGURE 7.…”

Paraffin-Inert Atmospheric Solid Analysis Probe: A Fast and Easy Approach To Characterize Extremely Air-Sensitive Organometallic Complexes by Mass Spectrometry

“…This latter ionization mode has been established by McEwen in 2005 and allows analysis of pure or solution samples directly deposited on a glass tip, where the analyte is desorbed by a hot nitrogen flux and ionized by nitrogen plasma generated by corona discharge . The ASAP source has been used in many applications for both targeted analysis − and untargeted analysis. − Unlike other techniques that require uncontrolled multisophisticated preparation steps or modified setups, , in our new simple approach, referred to as paraffin-inert ASAP (piASAP), a capillary tube containing air-sensitive compounds (liquid or solid) is sealed with a paraffin plug under inert atmospheric condition. The sample is thus protected in a sealed glass capillary under inert atmosphere, and it can be transported and carried away as long as the paraffin plug is intact.…”

Gas‐Phase Chemistry and Mass Spectrometry ofGe‐,Sn‐ andPb‐Containing Compounds

“…However, the variety of ionization techniques presently available, such as electron ionization (EI), chemical ionization (CI), fast atom bombardment (FAB), matrix assisted laser desorption ionization (MALDI) and electrospray (ESI), among others, coupled with the high resolution and high mass capabilities of modern instruments can nowadays circumvent many of the early problems. Thus, mass spectrometry can increasingly provide a complementary approach for the characterization of organometallic compounds containing elements of group 14 of the periodic table 1,2 . This can be exemplified by germenes and stannanes, an area that has enjoyed phenomenal growth and interest in recent years, because of their potential applications as synthons in organometallic and organic chemistry.…”