Organometallics最新文献

{"title":"Intramolecular Oxidative Addition Triggered by One-Electron Oxidation of Molybdenum(iii) Tris(anilide): Generation of Molybdenum(v) Imido Aryl Bis(anilide) by Autocatalysis","authors":"Albert Paparo*,&nbsp;Tobias Schindler,&nbsp;Jan van Leusen,&nbsp;Jessica Cook,&nbsp;Thomas P. Spaniol,&nbsp;Paul Kögerler,&nbsp;Manuel Temprado*,&nbsp;Christopher C. Cummins* and Jun Okuda*,&nbsp;","doi":"10.1021/acs.organomet.3c0050210.1021/acs.organomet.3c00502","DOIUrl":"https://doi.org/10.1021/acs.organomet.3c00502https://doi.org/10.1021/acs.organomet.3c00502","url":null,"abstract":"<p >One-electron oxidation of molybdenum(<span>iii</span>) tris(anilide) Mo(N[^<i>t</i>Bu]Ar)₃ (Ar: Ar^Me = 3,5-Me₂C₆H₃ and Ar^Ph = 3,5-Ph₂C₆H₃) led to intramolecular oxidative addition across the N–C_ipso bond of a ligated anilide to form the cationic Mo(<span>vi</span>) imido/aryl bis(anilide) complexes [Mo(N[^<i>t</i>Bu]Ar)₂(═N^<i>t</i>Bu)(Ar)][B(C₆F₅)₄]. One-electron reduction of [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)][B(C₆F₅)₄] allowed access to the neutral Mo(v) species [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)]. The d¹ electron configuration was confirmed through EPR spectroscopy and the Evans method. Compound [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)] was experimentally and theoretically shown to be stable against reductive elimination which would form the energetically less favorable Mo(N[^<i>t</i>Bu]Ar)₃. The high activation barrier has so far prevented Mo(N[^<i>t</i>Bu]Ar)₃ from isomerizing spontaneously to [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)]. An autocatalytic process was developed to access [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)] through reduction of [Mo(N[^<i>t</i>Bu]Ar^Me)₂(═N^<i>t</i>Bu)(Ar^Me)][B(C₆F₅)₄] by Mo(N[^<i>t</i>Bu]Ar)₃, which itself was converted into the oxidizing agent. Attempts to access stable Mo(<span>iv</span>) cations with 4,4′-bipyridine only resulted in labile binding of 4,4′-bipyridine to one or two molybdenum(<span>iii</span>) tris(anilide) complexes.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"529–535 529–535"},"PeriodicalIF":2.5,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flash Communication: Rearrangement of a tris-Carbene Ligand Precursor to an all-N-Bound tris-Imidazole Iron Complex: Flipping the Umbrella","authors":"Tom Hartmann,&nbsp;Lisa Pick,&nbsp;Frank W. Heinemann,&nbsp;Andreas Scheurer and Karsten Meyer*,&nbsp;","doi":"10.1021/acs.organomet.4c0044510.1021/acs.organomet.4c00445","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00445https://doi.org/10.1021/acs.organomet.4c00445","url":null,"abstract":"<p >Treatment of the ligand precursor H₃TIMMN^MesCl₃ (TIMMN^Mes = <i><b>t</b>ris</i>-[(3-mesityl-<b>im</b>idazol-2-ylidene)<b>m</b>ethyl]ami<b>n</b>e) with an excess of base yields the literature-known ferrous <i>tris</i>-<i>N</i>-heterocyclic carbene (NHC) complex [(TIMMN^Mes)Fe^IICl]Cl (<b>1-Cl</b>). In contrast, utilizing a substoichiometric amount of base initiates a unique rearrangement of all three NHC pendant arms to yield the tripodal, all-<i>N</i>-bound <i>tris</i>-imidazole [(<i>N</i>-TIMMN^Mes)Fe^IICl]Cl (<b>2-Cl</b>_<b>sol</b>). Divalent <b>2-Cl</b> and <b>2-PF</b>_<b>6</b> are fully characterized, structurally by single-crystal X-ray diffraction analysis and spectroscopically by ¹H NMR and ⁵⁷Fe Mössbauer spectroscopy as well as SQUID magnetization measurements, to demonstrate the influence of the change from a soft strong-field to a hard weak-field ligand. Optimized reaction conditions for the reproducible, high-yield carbene-to-imidazole rearrangement were developed in a series of experiments.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"464–467 464–467"},"PeriodicalIF":2.5,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Insight into Hydrodeoxygenation of Naphthols: Iridium-Catalyzed Ring Hydrogenation and Substrate-Catalyzed Dehydration","authors":"Christian Sant Gjermestad,&nbsp;Shuhei Kusumoto,&nbsp;Iván Flores-Linares,&nbsp;Giovanni Occhipinti,&nbsp;Erwan Le Roux,&nbsp;Hideaki Ando,&nbsp;Kyoko Nozaki* and Vidar R. Jensen*,&nbsp;","doi":"10.1021/acs.organomet.4c0046210.1021/acs.organomet.4c00462","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00462https://doi.org/10.1021/acs.organomet.4c00462","url":null,"abstract":"<p >The only molecular precatalysts offering high aromatic selectivity in hydrodeoxygenation (HDO) of phenolic and methyl ether lignin model compounds are hydroxy-tetraphenyl-cyclopentadienyl (CpOH) iridium complexes such as IrCpOH(H)₂PPh₃ (<b>Ir1</b>) [Kusumoto, S.; Nozaki, K. <i>Nat. Commun.</i> <b>2015</b>, 6, 6296]. Here, we synthesized a variant (<b>Ir1L</b>) in which the CpOH and phosphine moieties are tethered and unlikely to dissociate from iridium. Surprisingly, unlike <b>Ir1</b>, <b>Ir1L</b> neither catalyzes HDO of phenylphenols nor the interconversion between naphthalene and tetralin. The density functional theory-calculated barriers for the corresponding reactions catalyzed by unmodified <b>Ir1</b> or <b>Ir1L</b> are high (&gt;44 kcal/mol), suggesting that the observed activity of <b>Ir1</b> in these reactions is due to catalyst initiation. In contrast, intact <b>Ir1</b> and <b>Ir1L</b> both appear to catalyze HDO of naphthols. Notably, the calculations show that <b>Ir1</b> and <b>Ir1L</b> both mediate initial ring hydrogenation to 1,2-dihydronaphthol (<b>2H</b>), while only <b>Ir1L</b> can continue hydrogenation to 1,2,3,4-tetrahydronaphthol (<b>4H</b>). The subsequent substrate-catalyzed dehydration of <b>2H</b> leads directly to naphthalene, whereas that of <b>4H</b> leads to 1,2-dihydronaphthalene and, via hydrogenation, to tetralin. The calculations are thus consistent with the near-perfect aromatic selectivity observed at short reaction times using <b>Ir1</b> and the mixture (19:81) of naphthalene and tetralin obtained by using <b>Ir1L</b>.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"536–546 536–546"},"PeriodicalIF":2.5,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Reactivity of a Paramagnetic Iron Phosphaethynolate Complex","authors":"Duleeka C. Wannipurage,&nbsp;Austin D. Chivington,&nbsp;Yaroslav Losovyj,&nbsp;Maren Pink and Jeremy M. Smith*,&nbsp;","doi":"10.1021/acs.organomet.4c0044710.1021/acs.organomet.4c00447","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00447https://doi.org/10.1021/acs.organomet.4c00447","url":null,"abstract":"<p >The bulky iron(II) tris(carbene)borate complex PhB(AdIm)₃FeCl reacts with equimolar NaPCO to afford PhB(AdIm)₃Fe(PCO) as a rare example of a paramagnetic phosphaethynolate complex. Although thermally and photochemically unstable, there is no evidence that either of these conditions leads to the formation of an iron phosphido complex. However, in the presence of excess NaPCO, thermolysis of PhB(AdIm)₃Fe(PCO) yields a dinuclear iron complex in which a new side-bound diphosphene ligand is stabilized by <i>N</i>-heterocyclic carbene and borate groups. These results hint at the utility of paramagnetic complexes for enlarging the scope of phosphaethynolate chemistry.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"468–471 468–471"},"PeriodicalIF":2.5,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flash Communication: Flexibility of a Biologically Inspired Ligand Framework for Intramolecular C-H Activation.","authors":"Jewelianna M Moore, Yun Ji Park, Alison R Fout","doi":"10.1021/acs.organomet.4c00454","DOIUrl":"10.1021/acs.organomet.4c00454","url":null,"abstract":"<p><p>High-valent iron complexes play a crucial role in the oxidation of organic substrates, especially in C-H bond functionalization reactions in biology. This paper investigates the reactivity of nonporphyrin tripodal ligands featuring a secondary coordination sphere, focusing on their prospective ability to stabilize high-valent iron-oxo species. Using NMR spectroscopy and X-ray crystallography, we detail the formation of an Fe(III)-alkoxide complex through intramolecular C-H bond activation, providing insight into the potential transient formation of a high-valent iron-oxo intermediate. While attempts to observe an Fe(IV)-oxo complex were unsuccessful, our findings underscore the significance of the ligand electronic environment in stabilizing reactive iron species for C-H bond activation.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"472-476"},"PeriodicalIF":2.5,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11816012/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flash Communication: Flexibility of a Biologically Inspired Ligand Framework for Intramolecular C–H Activation","authors":"Jewelianna M. Moore,&nbsp;Yun Ji Park and Alison R. Fout*,&nbsp;","doi":"10.1021/acs.organomet.4c0045410.1021/acs.organomet.4c00454","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00454https://doi.org/10.1021/acs.organomet.4c00454","url":null,"abstract":"<p >High-valent iron complexes play a crucial role in the oxidation of organic substrates, especially in C–H bond functionalization reactions in biology. This paper investigates the reactivity of nonporphyrin tripodal ligands featuring a secondary coordination sphere, focusing on their prospective ability to stabilize high-valent iron-oxo species. Using NMR spectroscopy and X-ray crystallography, we detail the formation of an Fe(III)-alkoxide complex through intramolecular C–H bond activation, providing insight into the potential transient formation of a high-valent iron-oxo intermediate. While attempts to observe an Fe(IV)-oxo complex were unsuccessful, our findings underscore the significance of the ligand electronic environment in stabilizing reactive iron species for C–H bond activation.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"472–476 472–476"},"PeriodicalIF":2.5,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00454","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silver(I)-Catalyzed Stereochemical Isomerization of Cyclopropanols","authors":"Rajat Shankhdhar,&nbsp;Sylwia Górczyńska,&nbsp;Kacper Błaziak,&nbsp;Léonie Blanchard and Łukasz Woźniak*,&nbsp;","doi":"10.1021/acs.organomet.4c0043210.1021/acs.organomet.4c00432","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00432https://doi.org/10.1021/acs.organomet.4c00432","url":null,"abstract":"<p >Isomerization of cyclopropane-containing molecules offers a direct pathway to access all of their diastereoisomers. Current catalytic methods, however, are largely confined to isomerization of carbonyl- and vinyl-substituted cyclopropanes. We report a catalytic isomerization of cyclopropanols, which converts readily accessible <i>cis</i>-1,2-disubstituted cyclopropanols into their more stable, yet often less accessible, <i>trans</i>-isomers. This enables a straightforward access to both diastereoisomers of these small-ring molecules. Mechanistic studies indicate the catalytic reactivity of silver homoenolates.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 3","pages":"520–528 520–528"},"PeriodicalIF":2.5,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00432","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tetradentate Platinum(II) Complex with a 6/5/7 Metallocycle","authors":"Yunqi Lu,&nbsp;Feng Zhan,&nbsp;Guijie Li* and Yuanbin She*,&nbsp;","doi":"10.1021/acs.organomet.4c0044310.1021/acs.organomet.4c00443","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00443https://doi.org/10.1021/acs.organomet.4c00443","url":null,"abstract":"<p >Tetradentate Pt(II) complexes are promising phosphorescent materials for photocatalysts and solar cells, especially as robust emitters and sensitizers in organic light-emitting diodes (OLEDs). In this work, we report a tetradentate Pt(II) complex, PtZL7, which utilizes a conjugately linked ligand of a phenylquinoline/benzimidazole/phenoxy anion to form a novel 6/5/7 metallocycle. To the best of our knowledge, PtZL7 is a rare example of a tetradentate Pt(II) complex containing a fused 6/5/7 metallocycle. The molecular geometry and photophysical and excited-state properties of PtZL7 were systematically investigated through experimental and theoretical studies. PtZL7 has a highly distorted molecular geometry and limits intermolecular interactions. The PtZL7 exhibited red region emission with peak wavelengths at 617 and 607 nm and fwhm values of 125 and 115 nm at room temperature (RT) in toluene and poly(methyl methacrylate) (PMMA) film, respectively, and a high quantum efficiency of 62% in PMMA film. According to time-dependent density functional theory (TD-DFT) and NTO analyses, there is a mixed ³MLCT and ³ILCT transition in the T₁ state of PtZL7 at RT, which is responsible for broader spectra.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"403–409 403–409"},"PeriodicalIF":2.5,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143088574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"N,N,C Heteroscorpionates as a Platform for Monovalent Ni Chemistry","authors":"Li Gu,&nbsp; and ,&nbsp;Alex McSkimming*,&nbsp;","doi":"10.1021/acs.organomet.4c0045010.1021/acs.organomet.4c00450","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00450https://doi.org/10.1021/acs.organomet.4c00450","url":null,"abstract":"<p >We report herein the synthesis and characterization of a number of monovalent Ni complexes bound by a class of <i>N</i>,<i>N</i>,C heteroscorpionate ligands and their derivatives. One-electron reduction of Ni²⁺ complexes supported by less bulky heteroscorpionates led to a thermally unstable Ni⁺ species that could be trapped as the corresponding PPh₃ adduct. In situ reaction of the aforementioned Ni⁺ complex with a bulky aryl azide affords a transient Ni³⁺ imide, for which attack of the C donor at the N_imido atom, followed by rapid isomerization, furnishes a three-coordinate Ni⁺ complex ligated by a new type of “expanded” <i>N</i>,<i>N</i>,C chelate. An <i>N</i>,<i>N</i>,C heteroscorpionate ligand with large Ph₂(CH₃)C– substituents was able to support a thermally stable, isolable Ni⁺ complex, in which a phenyl group of one Ph₂(CH₃)C– unit binds Ni in an η² fashion. This complex proved to be relatively unreactive toward organic azides. The labile C donor in the former Ni⁺ complex could be trapped via the addition of B(C₆F₅)₃, affording a zwitterionic Ni⁺ complex. All Ni⁺ species were characterized by electron paramagnetic resonance (EPR) spectroscopy, which was corroborated by density functional theory (DFT) calculations. Our results are expected to guide future efforts by ourselves and others in the pursuit of low-valent Ni complexes and Ni imides in general.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"418–426 418–426"},"PeriodicalIF":2.5,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00450","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143088165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Back with the Flash Communication","authors":"Paul J. Chirik*,&nbsp;","doi":"10.1021/acs.organomet.4c0049710.1021/acs.organomet.4c00497","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00497https://doi.org/10.1021/acs.organomet.4c00497","url":null,"abstract":"","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 1","pages":"1–2 1–2"},"PeriodicalIF":2.5,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143087786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}