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Updated: May 3, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Use of Microwave Dielectric Spectroscopy for the In Actu Assessment of Frustrated Lewis Pair Encounter Complexes
Cihang Yu1, Jamie A Leitch1, Lukas Gierlichs2
1Department of Pharmaceutical and Biological Chemistry, University College London, School of Pharmacy, 29-39 Brunswick Square, Bloomsbury, London W1CN 1AX, U.K.
Abstract:
Frustrated Lewis pairs (FLPs) offer an important and promising paradigm for main group catalysis. Reported here is the use of microwave dielectric spectroscopy for the in actu detection of FLP encounter complexes. This technique focuses on the room-temperature measurement of the loss component of microwave permittivity (ε2) over the bandwidth from 0.5 to 6.8 GHz. The microwave loss measured for a Lewis pair in a toluene host solution is compared with the losses of the individual components when measured separately, and the difference in loss Δε2 is used to characterize the electrostatic interaction between the pair. The Δε2 value shows a direct correlation with an ability for the FLP encounter complex to split hydrogen gas and abstract hydrogen from γ-terpinene and has led to the identification of a novel FLP encounter complex, tris-pentafluorophenyl borane-eucalyptol pairing.
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