{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T15:18:23Z","timestamp":1791299903966,"version":"4.1.0"},"reference-count":37,"publisher":"American Chemical Society (ACS)","issue":"17","license":[{"start":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T00:00:00Z","timestamp":1744761600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000165","name":"Division of Chemistry","doi-asserted-by":"publisher","award":["CHE-2339280"],"award-info":[{"award-number":["CHE-2339280"]}],"id":[{"id":"10.13039\/100000165","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006770","name":"American Chemical Society Petroleum Research Fund","doi-asserted-by":"publisher","award":["66140-DNI3"],"award-info":[{"award-number":["66140-DNI3"]}],"id":[{"id":"10.13039\/100006770","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,4,30]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Nature operates a variety of challenging oxidation reactions through intermediates bearing tetravalent iron centers bound to a terminal oxo ligand. The high-spin (S = 2) electronic configuration is believed to be particularly important in C\u2013H activation reactions mediated by iron(IV)-oxo species. Coordination environments that promote high-spin ground states obviate the need for spin-state crossing to access this state and can promote rapid oxidation reactivity. As a result, however, synthetic iron(IV)-oxo species with S = 2 ground states tend to exhibit poor thermal stabilities, which has hampered a broader elucidation of their reactivity profiles. In this work, we report the synthesis of a remarkably stable high-spin iron(IV)-oxo complex that localizes the Fe\u2550O unit within a rigid organic macrocycle. This design results in essentially unlimited stability at ambient temperatures and a half-life of 21 h at 70 \u00b0C in CH3CN, endowing this compound with the highest thermal stability for a high-spin FeIV\u2550O complex reported to date. The ligand\u2019s steric profile shuts down intermolecular reactivity with potential O atom acceptors and hydrocarbons bearing weak C\u2013H bonds, but proton-coupled electron transfer reactivity with 2,4,6-tri-tert-butylphenol (TTBP) occurs readily at room temperature despite its steric bulk.<\/jats:p>","DOI":"10.1021\/jacs.5c00503","type":"journal-article","created":{"date-parts":[[2025,4,16]],"date-time":"2025-04-16T13:27:11Z","timestamp":1744810031000},"page":"14031-14035","source":"Crossref","is-referenced-by-count":15,"title":["Generation and Reactivity\nof a High-Spin Iron(IV)-Oxo\nComplex That Is Stable at Ambient Temperatures"],"prefix":"10.1021","volume":"147","author":[{"given":"Christopher D.","family":"Hastings","sequence":"first","affiliation":[{"name":"University of Rochester , , , ,","place":["Rochester, New York, United States, 14627"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucy S. X.","family":"Huffman","sequence":"additional","affiliation":[{"name":"University of Rochester , , , ,","place":["Rochester, New York, United States, 14627"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5461-1825","authenticated-orcid":true,"given":"William W.","family":"Brennessel","sequence":"additional","affiliation":[{"name":"University of Rochester , , , ,","place":["Rochester, New York, United States, 14627"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3113-7347","authenticated-orcid":true,"given":"Brandon R.","family":"Barnett","sequence":"additional","affiliation":[{"name":"University of Rochester , , , ,","place":["Rochester, New York, United States, 14627"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2025,4,16]]},"reference":[{"issue":"14","key":"2026090713163640400_cit1","doi-asserted-by":"publisher","first-page":"11974","DOI":"10.1021\/acs.chemrev.2c00106","article-title":"Designing\nArtificial Metalloenzymes by Tuning of the Environment beyond the\nPrimary Coordination Sphere","volume":"122","author":"Van Stappen","year":"2022","journal-title":"Chem. 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Acad.\nSci. U. S. A."},{"issue":"8","key":"2026090713163640400_cit36","doi-asserted-by":"publisher","first-page":"2556","DOI":"10.1021\/ja0305151","article-title":"Utilization of Hydrogen\nBonds to Stabilize M-O(H) Units: Synthesis and Properties of Monomeric\nIron and Manganese Complexes with Terminal Oxo and Hydroxo Ligands","volume":"126","author":"MacBeth","year":"2004","journal-title":"J. Am. Chem. 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