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Updated: Jul 2, 2026

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
Alkali metal reductions of organic molecules: why mediated electron transfer from lithium is faster than direct
Neil V Rees1, Ronan Baron, Neil M Kershaw
1Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford, OX1 3QZ, UK.
Abstract:
Lithium metal reductions are widely employed in organic synthesis, where it is common to employ a "mediator" to speed up the electron transfer kinetics. We present experimental data for the electrode kinetics of the reduction of the most common mediator, 4,4'-di-tert-butyl-1,1'-biphenyl (DBB) in tetrahydrofuran (THF) over a range of temperatures. Using corresponding data for the oxidation of lithium we present quantitative estimates of the kinetic advantage for the use of DBB as a mediator in lithium reductions, over, in particular, direct reduction using lithium metal.
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