Nils Ostermann, Nils Rotthowe, A. Claudia Stückl and Inke Siewert*,
{"title":"(Electro)chemical N2 Splitting by a Molybdenum Complex with an Anionic PNP Pincer-Type Ligand","authors":"Nils Ostermann, Nils Rotthowe, A. Claudia Stückl and Inke Siewert*, ","doi":"10.1021/acsorginorgau.3c00056","DOIUrl":null,"url":null,"abstract":"<p >Molybdenum(III) complexes bearing pincer-type ligands are well-known catalysts for N<sub>2</sub>-to-NH<sub>3</sub> reduction. We investigated herein the impact of an anionic PNP pincer-type ligand in a Mo(III) complex on the (electro)chemical N<sub>2</sub> splitting ([<i>L</i>MoCl<sub>3</sub>]<sup>−</sup>, <b>1</b><sup>–</sup>, <i>L</i>H = 2,6-bis((di-<i>tert</i>-butylphosphaneyl)methyl)-pyridin-4-one). The increased electron-donating properties of the anionic ligand should lead to a stronger degree of N<sub>2</sub> activation. The catalyst is indeed active in N<sub>2</sub>-to-NH<sub>3</sub> conversion utilizing the proton-coupled electron transfer reagent SmI<sub>2</sub>/ethylene glycol. The corresponding Mo(V) nitrido complex <b>2H</b> exhibits similar catalytic activity as <b>1H</b> and thus could represent a viable intermediate. The Mo(IV) nitrido complex <b>3</b><sup><i>–</i></sup> is also accessible by electrochemical reduction of <b>1</b><sup>–</sup> under a N<sub>2</sub> atmosphere. IR- and UV/vis-SEC measurements suggest that N<sub>2</sub> splitting occurs via formation of an “overreduced” but more stable [(<i>L</i>(N<sub>2</sub>)<sub>2</sub>Mo<sup>0</sup>)<sub>2</sub>μ-N<sub>2</sub>]<sup>2–</sup> dimer. In line with this, the yield in the nitrido complex increases with lower applied potentials.</p>","PeriodicalId":29797,"journal":{"name":"ACS Organic & Inorganic Au","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsorginorgau.3c00056","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Organic & Inorganic Au","FirstCategoryId":"1085","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsorginorgau.3c00056","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Molybdenum(III) complexes bearing pincer-type ligands are well-known catalysts for N2-to-NH3 reduction. We investigated herein the impact of an anionic PNP pincer-type ligand in a Mo(III) complex on the (electro)chemical N2 splitting ([LMoCl3]−, 1–, LH = 2,6-bis((di-tert-butylphosphaneyl)methyl)-pyridin-4-one). The increased electron-donating properties of the anionic ligand should lead to a stronger degree of N2 activation. The catalyst is indeed active in N2-to-NH3 conversion utilizing the proton-coupled electron transfer reagent SmI2/ethylene glycol. The corresponding Mo(V) nitrido complex 2H exhibits similar catalytic activity as 1H and thus could represent a viable intermediate. The Mo(IV) nitrido complex 3– is also accessible by electrochemical reduction of 1– under a N2 atmosphere. IR- and UV/vis-SEC measurements suggest that N2 splitting occurs via formation of an “overreduced” but more stable [(L(N2)2Mo0)2μ-N2]2– dimer. In line with this, the yield in the nitrido complex increases with lower applied potentials.
期刊介绍:
ACS Organic & Inorganic Au is an open access journal that publishes original experimental and theoretical/computational studies on organic organometallic inorganic crystal growth and engineering and organic process chemistry. Short letters comprehensive articles reviews and perspectives are welcome on topics that include:Organic chemistry Organometallic chemistry Inorganic Chemistry and Organic Process Chemistry.