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Reduction of K⁺ or Li⁺ in the Heterobimetallic Electride K⁺[LiN(SiMe₃)₂]e.

ABSTRACT: Given their very negative redox potential (e.g., Li⁺ → Li(0), -3.04 V; K⁺ → K(0), -2.93 V), chemical reduction of Group-1 metal cations is one of the biggest challenges in inorganic chemistry: they are widely accepted as irreducible in the synthetic chemistry regime. Their reduction usually requires harsh electrochemical conditions. Herein we suggest a new strategy: via a heterobimetallic electride intermediate and using the nonbinding "free" electron as reductant. Based on our previously reported K⁺[LiN(SiMe₃)₂]e^- heterobimetallic electride, we demonstrate the reducibility of both K⁺ and Li⁺ cations. Moreover, we find that external Lewis base ligands, namely tris[2-(dimethylamino)ethyl]amine (Me₆Tren) or 2,2,2-cryptand, can exert a level of reducing selectivity by preferably binding to Li⁺ (Me₆Tren) or K⁺ (2,2,2-cryptand), hence pushing the electron to the other cation.

SUBMITTER: Davison N

PROVIDER: S-EPMC10416298 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Reduction of K+ or Li+ in the Heterobimetallic Electride K+[LiN(SiMe3)2]e.

Davison Nathan N Waddell Paul G PG Lu Erli E

Journal of the American Chemical Society 20230721 31

Given their very negative redox potential (e.g., Li+ → Li(0), -3.04 V; K+ → K(0), -2.93 V), chemical reduction of Group-1 metal cations is one of the biggest challenges in inorganic chemistry: they are widely accepted as irreducible in the synthetic chemistry regime. Their reduction usually requires harsh electrochemical conditions. Herein we suggest a new strategy: via a heterobimetallic electride intermediate and using the nonbinding "free" electron as reductant. Based on ...[more]

PMID: 37478322

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