Practical approaches to the ESI-MS analysis of catalytic reactions

Abstract

Electrospray ionization mass spectrometry (ESI-MS) is a soft ionization technique commonly coupled with liquid or gas chromatography for the identification of compounds in a one-time view of a mixture (for example, the resulting mixture generated by a synthesis). Over the past decade, Scott McIndoe and his research group at the University of Victoria have developed various methodologies to enhance the ability of ESI-MS to continuously monitor catalytic reactions as they proceed. The power, sensitivity and large dynamic range of ESI-MS have allowed for the refinement of several homogenous catalytic mechanisms and could potentially be applied to a wide range of reactions (catalytic or otherwise) for the determination of their mechanistic pathways. In this special feature article, some of the key challenges encountered and the adaptations employed to counter them are briefly reviewed.

Elusive Reaction Intermediates in Solution Explored by ESI‐MS: Reverse Periscope for Mechanistic Investigations

“…[7,11] Indeed, ionization processes which Just as periscopes allow as ubmarine to visually searchfor objects above the surface of the sea, in areversed periscope fashion electrospray mass spectrometry (ESI-MS) can analyzethe compounds at the gas phase/liquid phase interface for chemical entities whichmay exist in solution. The challenge is the identification and structural characterization of key elusive reaction intermediates in chemical transformations,i ntermediates whichare able to explain howc hemical processes occur.T his Minireview summarizes recent selected publications on the use of ESI-MS techniques for studying solution intermediates of homogeneous chemical reactions.…”

“…[7] Moreover the applicability of the technique can be widened by appending ionic tags to the reactant, thus allowing non-ionizable species to be sampled from solution and studied. [8] Thepotential of this technique can be complemented and increased by MS n (n:m ultiple steps of product ion analysis) performance,ion mobility,ion spectroscopy, [9] and computational studies.…”

Reaction Intermediates Kinetics in Solution Investigated by Electrospray Ionization Mass Spectrometry: Diaurated Complexes

“…[1][2][3][4][5] The introduction of electrospray ionization (ESI) allowed direct probing of reaction mixtures and ESI-MS was established as a method for "fishing out" reaction intermediates. 6,7 A big advantage of using ESI-MS is its sensitivity.…”

Morita–Baylis–Hillman adducts as building blocks of heterocycles: a simple approach to 4-substituted pyrazolones, and mechanism investigation via ESI–MS(/MS)

“…''fishing'', this reaction seems ideal to ESI(? )-MS(/MS) monitoring [77][78][79][80][81]. This technique has offered an exceptional tool for mechanistic studies, providing proper and continuous [82] snapshots of the ionic composition of reaction solutions.…”