Mass Spectrometry of Organoaluminum Derivatives

Abstract

Mass spectrometry has been applied to the characterization of organoaluminum compounds in work that dates back to the introduction of the first commercial instruments. As new ionization methods and associated instrumentation were developed, they have been applied to more difficult analyses so as to characterize the compounds of increasingly higher molecular weight, low volatility and ionic organoaluminum compounds. In thifs chapter, practical advice for performing these analyses, and choice of ionization method(s) to be applied is provided, as well as a representative survey of the various mass spectrometric techniques that have been applied to analysis of organoaluminum compounds.

Oxidation of Methylalumoxane Oligomers: A Theoretical Study Guided by Mass Spectrometry

“…This led us to propose that the byproduct of oxidation and rearrangement (Me 2 AlOAlMe 2 ) was involved in the aging process. Anions and cations derived from this material have been detected in MAO using [Bu 4 N]­[Cl] and silicone grease as additives. However, Me 2 AlOAlMe 2 is not stable in its monomeric form, and indeed has defied structural characterization beyond the fact that it is associated in condensed phase .…”

A mechanistic investigation of the Pd-catalyzed cross-coupling betweenN-tosylhydrazones and aryl halides

“…29 Flow injection systems have also been developed to facilitate sample delivery on a nL/min and µL/min scale enabling injection of up to 1200 samples per day without carryover. 30 In terms of air-and moisture-free sample introduction, some techniques have been described whereby a nitrogenous atmosphere is either attached to the MS source, such as a glove bag 31,32 and a small glove chamber. 33 On a larger scale, a glovebox can be modified to accommodate a feedthrough port for tubing going directly into the MS source.…”

Ionization methods for the mass spectrometry of organometallic compounds

“…Keeping solutions away from air and moisture is straightforward with gas‐tight syringes or pressurized Schlenk flasks as delivery methods, and cations and anions both provide good ESI response (see Figure for examples) . There are also well‐developed derivatization strategies that exploit the reactivity or affinity of neutral complexes for charged species . Protic complexes can be deprotonated to form [M − H] − ions .…”