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Testing the Push-Pull Hypothesis: Lewis Acid Augmented N2 Activation at Iron.

ABSTRACT: We present a systematic investigation of the structural and electronic changes that occur in an Fe(0)-N2 unit (Fe(depe)2(N2); depe = 1,2-bis(diethylphosphino)ethane) upon the addition of exogenous Lewis acids. Addition of neutral boranes, alkali metal cations, and an Fe2+ complex increases the N-N bond activation (? ?NN up to 172 cm-1), decreases the Fe(0)-N2 redox potential, polarizes the N-N bond, and enables -N protonation at uncommonly anodic potentials. These effects were rationalized using combined experimental and theoretical studies.

SUBMITTER: Geri JB

PROVIDER: S-EPMC5965694 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Testing the Push-Pull Hypothesis: Lewis Acid Augmented N2 Activation at Iron.

Geri Jacob B JB Shanahan James P JP Szymczak Nathaniel K NK

Journal of the American Chemical Society 20170417 16

We present a systematic investigation of the structural and electronic changes that occur in an Fe(0)-N2 unit (Fe(depe)2(N2); depe = 1,2-bis(diethylphosphino)ethane) upon the addition of exogenous Lewis acids. Addition of neutral boranes, alkali metal cations, and an Fe2+ complex increases the N-N bond activation (Δ νNN up to 172 cm-1), decreases the Fe(0)-N2 redox potential, polarizes the N-N bond, and enables -N proto ...[more]

PMID: 28414226

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