Fast-Atom Bombardment Mass Techniques

The mass spectrometry of diazo compounds was reviewed by Zeller (1983) and by Lebedev (1991). It is difficult to record mass spectra of diazonium salts using conventional techniques. With the water thermospray method, however, Schmelzeisen-Redeker et al. (1985) observed the diazonium ion and various fragments such as [Ar+ - N2 + 2H]+ and [Ar + N2 + H20]+. Ambroz et al. (1988) applied the fast atom bombardment (FAB) technique using a 3-nitrobenzylalcohol matrix. Peaks for ArNJ, Ar+, and [M + ArN2]+ and further peaks due to solvated ions were found. 

Fast atom bombardment mass spectrometry and related techniques. J. M. Miller, Adv. Inorg. Chem. Radiochem., 1984,28,1 (118). 

In line with the policy of Advances to provide periodic coverage of major developments in physical methodology for the study of carbohydrates, A. Dell (London) here surveys the use of fast-atom-bombardment mass spectrometry in application to carbohydrates. This technique has achieved rapid prominence as the soft ionization technique of choice for structural investigation of complex carbohydrate sequences in biological samples. The author s extensive personal involvement in this field makes her chapter a critical, state-of-the-art overview for the specialist, as well as a valuable primer for the reader unfamiliar with this technique. 

Mass spectrometry (MS) in its various forms, and with various procedures for vaporization and ionization, contributes to the identification and characterization of complex species by their isotopomer pattern of the intact ions (usually cation) and by their fragmentation pattern. Upon ionization by the rough electron impact (El) the molecular peak often does not appear, in contrast to the more gentle field desorption (FD) or fast-atom bombardment (FAB) techniques. An even more gentle way is provided by the electrospray (ES) method, which allows all ionic species (optionally cationic or anionic) present in solution to be detected. Descriptions of ESMS and its application to selected problems are published 45-47 also a representative application of this method in a study of phosphine-mercury complexes in solution is reported.48... 

Other MS based analytical approaches have occasionally been applied to ancient resin samples, in particular for paint varnishes. Such techniques include FABS (fast atom bombardment mass spectrometry) [35], MALDI (matrix assisted laser desorption-ionization mass spectrometry) and GALDI (graphite assisted laser desorption-ionization mass spectrometry) [36 38]. 

Numerous chromatographic methods coupled with MS have been developed for quaternary ammonium compounds. HPLC and fast atom bombardment mass spectrometry (FAB-MS) techniques have been applied to analyse concentrations of alkyldimethylbenzyl ammonium... 

A novel pigment has been isolated from the petals of Rosa hybrida with complex chromatographic techniques and the structure was elucidated with spectroscopic methods and high resolution fast-atom bombardement mass spectrometry, lH NMR, and FTIR. Anthocyanins were extracted from 7.9 kg of petals of Rosa hybrida cv. M me Violet with 80 per cent aqueous ACN containing 0.1 per cent TFA. The extract was purified in a Sephadex LH-20 column, and the fraction eluted with 80 per cent ACN was further fractionated in a HP-20 column using water, 15, 20 and 30 per cent ACN as mobile phases. The last fraction was lyophilized and separated by preparative RP-HPLC using an ODS column (50 X 5 cm i.d.). Solvents were 0.5 per cent aqueous TFA (A) and water-methanol... 

The development of mass spectrometric techniques, such as fast atom bombardment mass spectrometry (FAB-MS), ° ° Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), ° and tandem mass spectrometry (MS"), ° allowed enantiodiscrimination of chiral ion-dipole complexes the gas phase. These techniques and others will be illustrated in detail in the next Section 3. 

In secondary-ion mass spectrometery (SIMS) and its sister technique fast atom bombardment mass spectrometry (FARMS), a surface is bombarded with energetic particles, and the kinetic energy of the particles converts substrate and chemisorbed atoms and molecules to gas-phase species. The ejected (or sputtered) material is subsequently interrogated using various analytical tools, such as lasers and mass spectrometers, to indirectly deduce information about the initial surface. The relationships between sputtered material and the surface, however, are not always clear, and erroneous conclusions are easily made. Computer simulations have demonstrated that a fundamental understanding of the sputtering process is required to interpret experimental data fully ... 

Two methods were used to measure the chlorine leaving-group KIE for the 5n2 reduction of benzyl chloride to toluene by sodium borohydride in DMSO at 30 °C. One procedure involved the classical IRMS technique. The second method was a new technique in which the ratio of the chlorine isotopes was obtained by fast atom bombardment mass spectrometry on silver chloride recovered from the reaction. The KIE values found by the two methods were 1.007 and 1.008, respectively,... 

The structures of the novel ferrocenyl dendrimers 1-6 were straightforwardly established by a variety of spectroscopic and analytical techniques including H, C, and Si NMR and IR spectroscopies, fast atom bombardment mass spectrome-... 

H Oka, Y Ikai, F Kondo, N Kawamura, J Hayakawa, K Masuda, KI Harada, M Suzuki. Development of a condensation technique for thin-layer chromatography fast-atom bombardment mass spectrometry of non-visible compounds. Rapid Commun Mass Spectrom 6 89-94, 1992. 

Fast Atom Bombardment Mass Spectrometric Technique and Ion Guns... 

The FABMS (Fast Atom Bombardment Mass Spectrometry) technique Is reviewed In this chapter with emphasis upon laboratory Instrumentation and procedures. 

Although the FABMS (Fast Atom Bombardment Mass Spectrometry) technique has only been in use for a few short years (since 1981), it traces its roots back well over a century (1). It has been observed that the bombardment of a surface by energetic ions produces the desorption of atoms and molecules from the surface of the target. This process, known as Sputtering, produces a yield (number of atoms sputtered per incident ion) which generally increases with the energy, the mass and the incidence angle of bombardment (2). 

Fast atom bombardment mass spectrometry (FABMS) has become an important addition to the ionization techniques available to the analytical chemist in recent years. It has been particularly useful in a number of diverse applications which include molecular weight determinations at high mass, peptide and oligosaccharide sequencing, structural analysis of organic compounds, determination of salts and metal complexes, and the analysis of ionic species in aqueous solutions. This paper will focus on some aspects of the quantitative measurement of ionic species in solution. The reader is referred to a more comprehensive review for more details of some of the examples given here as well as other applications (1). 

Fast atom bombardment mass spectrometry (FABMS) has been used to investigate the selectivity of monocyclic crown ethers for Group IA metal cations in competition experiments (56). We applied this semiquantitative technique for the first time to bis crown ethers (51, 53) and observed that (7) and (8) in competition experiments with Li +, Na+, K+, and Cs+ exhibited exclusive selectivity for K+ (Fig. 9). Ligands (9) and (10) however displayed no preference for any particular alkali metal cation. 

Single-crystal X-ray crystallography remains the only definitive technique for the structural characterization of heteronuclear gold cluster compounds, although other techniques, in particular Mossbauer, NMR, IR, and fast atom bombardment mass spectroscopies (FABMS), have yielded valuable information, especially concerning the nature of these species in solution. Electron spectroscopy, which has proved to be of great value in the identification of homonuclear gold cluster compounds (210) has received little attention by workers in this area,... 

FAST-ATOM BOMBARDMENT MASS SPECTROMETRY AND RELATED TECHNIQUES... 

In conclusion, I hope that I have shown that fast-atom bombardment mass spectrometry is a potentially useful tool for the synthetic chemist working in many areas of inorganic, organometallic, and coordination chemistry. In addition, as further fundamental research is done in the field with these applications in mind, the technique should become as routine as IR or NMR. Combined with developments in high-resolution NMR of solids, FAB should provide particularly useful data on supported catalytic reactions. Certainly FAB and the other complementary mass spectrometric techniques, mentioned in less detail, constitute a major way of quickly characterizing new compounds. 

Mass spectrometry is a standard spectroscopic technique for the characterisation of high molecular weight organic and inorganic compounds, but has until recently received little attention from the zeolite community. The surface composition of zeolites has been explored using fast atom bombardment mass spectrometry (FABMS)[66] and secondary ion mass spectrometry [67], but mass spectrometric analysis of the bulk composition of a zeolite or of adsorbed molecules has not until very recently been attempted. The practical difficulty is to vaporise the solid. Two different strategies have been proposed laser ablation and plasma desorption. 

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