[NiFe] dithiolene diphosphine complex for hydrogen gas activation: a Theoretic Insight

TL;DR

This study provides a detailed theoretical analysis of a [NiFe] dithiolene diphosphine complex, revealing that both nickel and iron components are essential for its ability to activate dihydrogen, advancing understanding of its catalytic mechanism.

Contribution

The paper introduces a comprehensive theoretical model that highlights the combined role of nickel and iron in the catalytic activity of the [NiFe] complex, surpassing previous models that considered only nickel.

Findings

Both nickel and iron are crucial for dihydrogen activation.

Theoretical insights align with experimental catalytic performance.

Iron's contribution is essential for the observed activity.

Abstract

A diphosphino-nickel-iron dithiolene complex, [Ni(bdt)(dppf)] (bdt = 1,2-benzenedithiolate, dppf = 1,1-bis(diphenylphosphino)ferrocene), has been recently found to be reasonably active on proton reduction to dihydrogen (J. Am. Chem. Soc. 2015, 137, 1109). Interestingly, this exceptional complex was found to be also reactive towards dihydrogen activation as indicated by the electrochemical investigation. However, a pure nickel dithiolene diphosphine theoretical mode, excluding the contributions from iron moiety, was applied to attribute the experimental catalytic observation. We have re-visited the theoretical approach in details for this [NiFe] catalyst and compared it with the non-active nickel dithiolene diphosphine complexes. We found that both nickel and iron moieties in this newly developed complex were imperative for the observed catalytic per-formance, particularly towards the activation of dihydrogen.