Fischer Indole Synthesis in the Gas Phase, the Solution Phase, and at the Electrospray Droplet Interface

  • Ryan M. Bain
  • Stephen T. Ayrton
  • R. Graham Cooks
Focus: Bio-Ion Chemistry: Interactions of Biological Ions with Ions, Molecules, Surfaces, Electrons, and Light : Research Article


Previous reports have shown that reactions occurring in the microdroplets formed during electrospray ionization can, under the right conditions, exhibit significantly greater rates than the corresponding bulk solution-phase reactions. The observed acceleration under electrospray ionization could result from a solution-phase, a gas-phase, or an interfacial reaction. This study shows that a gas-phase ion/molecule (or ion/ion) reaction is not responsible for the observed rate enhancement in the particular case of the Fischer indole synthesis. The results show that the accelerated reaction proceeds in the microdroplets, and evidence is provided that an interfacial process is involved.

Graphical Abstract



Electrospray Accelerated reactions Fischer indole synthesis 

Supplementary material

13361_2017_1597_MOESM1_ESM.docx (480 kb)
ESM 1(DOCX 479 kb)


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Copyright information

© American Society for Mass Spectrometry 2017

Authors and Affiliations

  • Ryan M. Bain
    • 1
  • Stephen T. Ayrton
    • 1
  • R. Graham Cooks
    • 1
  1. 1.560 Oval Drive Department of Chemistry and the Center for Analytical Instrumentation DevelopmentPurdue UniversityWest LafayetteUSA

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