Cysteine residue-bridged dinuclear Ni–Fe complexes related to [NiFe]-H2ases. (26th November 2021)

• Record Type: Journal Article
• Authors: Song, Li-Cheng; Zhang, Zhen-Qing; Gu, Zhen-Chao; Jiang, Kai-Yu
• Is Part Of: New journal of chemistry. Volume 45:Number 48(2021)
• Page Start: 22778
• Page End: 22786
• Publication Date: 2021-11-26
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d1nj03872a
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Cysteine residue-containing [NiFe]-H2 ase models 1–6 have been prepared for the first time and some of them were found to be catalysts for H2 production from HOAc under CV conditions. Abstract : To develop the biomimetic chemistry of [NiFe]-H2 ases, we have synthesized cysteine residue-containing [NiFe]-H2 ase mimics (diphosphine)Ni[SCH2 CH(CO2 Me)NHCOC5 H4 -η 5 ]2 Fe (1, diphosphine = Ph2 P(CH2 )2 PPh2 ; 2, Ph2 PCHCHPPh2 ; 3, 1, 2-(Ph2 P)2 C6 H4 ; 4, (Ph2 P)2 NCH2 C6 H4 Me- p ; 5, (Ph2 P)2 NCH2 CO2 Et; and 6, (Ph2 P)2 N-2-CH2 C5 H4 N) for the first time by a simple and convenient method. The full spectroscopic characterization of 1–6 along with X-ray crystallographic characterization of 1, 2 and 4 has proved that complexes 1–6 consist of two cysteine residue moieties that are bridged to their diphosphine-chelated Ni(ii ) centers and two η 5 -cyclopentadienyl-coordinated Fe(ii ) centers. On the basis of electrochemical and electrocatalytic studies, complexes 1 and 4 have been found to be catalysts for H2 production from HOAc with moderate i cat / i p and overpotential values under CV conditions. In addition, a possible 2E2C (E = electrochemical, C = chemical) mechanism is briefly suggested for this type of H2 evolution reaction (HER).