{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T00:34:52Z","timestamp":1761006892414,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2025,10,19]],"date-time":"2025-10-19T00:00:00Z","timestamp":1760832000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ibaraki University Priority Research Grant","award":["24ES0584"],"award-info":[{"award-number":["24ES0584"]}]},{"name":"Joint Usage\/Research Centre for Catalysis","award":["25DS0752"],"award-info":[{"award-number":["25DS0752"]}]},{"name":"Koyanagi Foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Coplanar tridentate nitrogen-donor ligands have been extensively employed to stabilize transition metal complexes by chelation. Some complexes exhibit interesting structures and photoluminescent properties. In this work, 2,6-bis(5-isopropyl-1H-pyrazole-3-yl)pyridine (denoted as L), its iron(II) and manganese(II) dichlorido complexes, and its bis-chelate iron(II) complexes, viz. [FeCl2(L)]\u00b72(MeOH) and [MnCl2(L)]\u00b72(MeOH), and [Fe(L)2](PF6) \u00b75(thf), respectively, were synthesized and characterized by single-crystal X-ray structural analysis. These solid-state structures contained N\u2013H donors that formed hydrogen bonds with the coordinated halogenide ions and lattice solvent molecules, methanol or tetrahydrofuran. The iron(II) and manganese(II) dichlorido complexes [FeCl2(L)]\u00b72(MeOH) and [MnCl2(L)]\u00b72(MeOH) displayed distorted trigonal pyramidal structures in the solid state. However, [FeCl2(L)]\u00b72(MeOH) was not stable in methanol and formed the bis-chelate iron(II) complex [Fe(L)2](FeCl4). Therefore, the bis-chelate iron(II) complex [Fe(L)2](PF6)\u00b75(thf) was also synthesized and structurally and spectroscopically authenticated.<\/jats:p>","DOI":"10.3390\/molecules30204128","type":"journal-article","created":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T10:44:10Z","timestamp":1760957050000},"page":"4128","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Iron(II) and Manganese(II) Coordination Chemistry Ligated by Coplanar Tridentate Nitrogen-Donor Ligand, 2,6-bis(5-isopropyl-1H-pyrazol-3-yl)pyridine"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4023-0025","authenticated-orcid":false,"given":"Kiyoshi","family":"Fujisawa","sequence":"first","affiliation":[{"name":"Department of Chemistry, Ibaraki University, Mito 310-8512, Ibaraki, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yurika","family":"Minakawa","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ibaraki University, Mito 310-8512, Ibaraki, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6079-5904","authenticated-orcid":false,"given":"David James","family":"Young","sequence":"additional","affiliation":[{"name":"James Watt School of Engineering, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1456","DOI":"10.1039\/CT9201701456","article-title":"CLXII\u2014Researches on residual affinity and co-ordination. 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