Synthesis, Structures and Chemical Reactivity of Dithiolato-Bridged Ni-Fe Complexes as Biomimetics for the Active Site of [NiFe]-Hydrogenases

Li-Cheng Song; Shuai Chen; Xiao-Feng Han; Zhen-Qing Zhang; Yin-Peng Wang; Yi-Xiong Dong

doi:10.3390/inorganics10070090

Inorganics (Jun 2022)

Synthesis, Structures and Chemical Reactivity of Dithiolato-Bridged Ni-Fe Complexes as Biomimetics for the Active Site of [NiFe]-Hydrogenases

Li-Cheng Song,
Shuai Chen,
Xiao-Feng Han,
Zhen-Qing Zhang,
Yin-Peng Wang,
Yi-Xiong Dong

Affiliations

Li-Cheng Song: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
Shuai Chen: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
Xiao-Feng Han: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
Zhen-Qing Zhang: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
Yin-Peng Wang: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
Yi-Xiong Dong: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China

DOI: https://doi.org/10.3390/inorganics10070090
Journal volume & issue: Vol. 10, no. 7
p. 90

Abstract

Read online

To develop the structural and functional modeling chemistry of [NiFe]-H2ases, we have carried out a study regarding the synthesis, structural characterization and reactivity of a new series of [NiFe]-H2ase model complexes. Thus, treatment of diphosphine dppb-chelated Ni complex (dppb)NiCl2 (dppb = 1,2-(Ph2P)2C6H4) with (dppv)Fe(CO)2(pdt) (dppv = 1,2-(Ph2P)2C2H2, pdt = 1,3-propanedithiolate) and NaBF4 gave dicarbonyl complex [(dppb)Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([A](BF4)2). Further treatment of [A](BF4)2 with Me3NO and Bu4NCN or KSCN afforded t-cyanido and t-isothiocyanato complexes [(dppb)Ni(pdt)Fe(CO)(t-R)(dppv)]BF4 ([1]BF4, R = CN; [2]BF4, R = NCS), respectively. While azadiphosphine MeN(CH2PPh2)2-chelated t-hydride complex [MeN(CH2PPh2)2Ni(pdt)Fe(CO)(t-H)(dppv)]BF4 ([3]BF4) was prepared by treatment of dicarbonyl complex [MeN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([B](BF4)2) with Me3NO and 1.5 MPa of H2, treatment of dicarbonyl complex [B](BF4)2 with Me3NO (without H2) in pyridine resulted in formation of a novel monocarbonyl complex [MeN(CH2PPh2)2Ni(SCHCH2CH2S)Fe(CO)(dppv)]BF4 ([4]BF4) via the unexpected sp3 C-H bond activation reaction. Furthermore, azadiphosphine PhN(CH2PPh2)2-chelated µ-mercapto complex [PhN(CH2PPh2)2Ni(pdt)Fe(CO)(µ-SH)(dppv)]BF4 ([5]BF4) was prepared by treatment of dicarbonyl complex [PhN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([C](BF4)2) with Me3NO and H2S gas, whereas treatment of azadiphosphine Ph2CHN(CH2PPh2)2-chelated dicarbonyl complex [Ph2CHN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppe)](BF4)2 ([D](BF4)2, dppe = 1,2-(Ph2P)2C2H4) with Me3NO⋅2H2O gave rise to µ-hydroxo complex [Ph2CHN(CH2PPh2)2Ni(pdt)Fe(CO)(µ-OH)(dppe)]BF4 ([6]BF4). All the possible pathways for formation of the new model complexes are briefly discussed, and their structures were fully characterized by various spectroscopic techniques and for six of them by X-ray crystallography.

Published in Inorganics

ISSN: 2304-6740 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Science: Chemistry: Inorganic chemistry
Website: http://www.mdpi.com/journal/Inorganics

About the journal

Abstract

Keywords