Hydrogenase biomimetics with redox-active ligands: Synthesis, structure and electrocatalytic studies on Fe2(CO)4(K2-dppn)(µ-edt) (edt = ethanedithiolate; dppn = 1,8-bis(diphenylphosphino)naphthalene)

Graeme Hogarth; Shishir Ghosh; Nathan Hollingsworth; Michael Richmond; Shariff Kabir; Shahed Rana

doi:10.20944/preprints201808.0477.v1

Preprint Article Version 1 Preserved in Portico This version is not peer-reviewed

Version 1 : Received: 28 August 2018 / Approved: 28 August 2018 / Online: 28 August 2018 (15:50:13 CEST)

Addition of the bulky redox-active diphosphine 1,8-bis(diphenylphosphino)naphthalene (dppn) to [Fe2(CO)6(-edt)] (1) (edt = 1,2-ethanedithiolate) affords [Fe2(CO)4(2-dppn)(-edt)] (3) as the major product, together with small amounts of a P-C bond cleavage product [Fe2(CO)5{1-PPh2(1-C10H7)}(-edt)] (2). The redox properties of 3 have been examined by cyclic voltammetry and it has been tested as a proton-reduction catalyst. It undergoes a reversible reduction at E1/2 = –2.18 V and exhibits two overlapping reversible oxidations at E1/2 = –0.08 V and E1/2 = 0.04 V. DFT calculations show that while the HOMO is metal-centred (Fe-Fe -bonding), the LUMO is primarily ligand-based but also contains an antibonding Fe-Fe contribution, highlighting the redox-active nature of the diphosphine. It is readily protonated upon addition of strong acids to afford two isomeric hydride complexes and catalyzes the electrochemical reduction of protons at Ep = –2.00 V in the presence of CF3CO2H. The catalytic current indicates that it is one of the most efficient diiron electrocatalysts for the reduction of protons, albeit operating at quite negative potential.

Hydrogenase biomimetics; dithiolate; proton-reduction; dppn; redox-active

CHEMISTRY, Inorganic & Nuclear Chemistry

Your full name

Your affiliation information (e.g., name of your university/institution/organization)

Not displayed online.

Your Email address (not made public)

Please leave your comment to this article below.

Mathematical equations can be typed in either LaTeX formats \\[ ... \\] or $$ ... $$, or MathML format <math> ... </math>. Try the LaTeX or MathML example.

Type equation:

Preview:

Copy equation into message below

Close menu

Please click a symbol to insert it into the message box below:

Please enter the link here:

Optionally, you can enter text that should appear as linked text:

Copy link into message below

Close menu

Please enter or paste the URL to the image here (please only use links to jpg/jpeg, png and gif images):

Copy image into message below

Close menu

Type author name or keywords to filter the list of references in this group (you can add a new citation under Bibliography):

No existing citations in Discussion Group

Wikify editor is a simple editor for wiki-style mark-up. It was written by MDPI for Sciforum in 2014. The rendering of the mark-up is based on Wiky.php with some tweaks. Rendering of mathematical equations is done with MathJax. Please send us a message for support or for reporting bugs.

Close menu

Please declare any conflicts of interest you may have with this paper, financial or otherwise.

I do not have a conflict of interest

I would like to declare a conflict of interest

Display my name on the website I want to get recognition for my comment on Publons

[what’s this?]. Link your accounts here

Captcha

Renew

I accept the following conditions:

Comments must follow the standards of professional discourse and should focus on the scientific content of the article. Insulting or offensive language, personal attacks and off-topic remarks will not be permitted. Comments must be written in English. Preprints reserves the right to remove comments without notice. Readers who post comments are obliged to declare any competing interests, financial or otherwise.

Notify me about updates to this article or when a peer-reviewed version is published.

Upload a Image(max file size 2MB)

Hydrogenase biomimetics with redox-active ligands: Synthesis, structure and electrocatalytic studies on Fe2(CO)4(K2-dppn)(µ-edt) (edt = ethanedithiolate; dppn = 1,8-bis(diphenylphosphino)naphthalene)

Abstract

Keywords

Subject

Comments (0)