Organometallics最新文献

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N,N,C Heteroscorpionates as a Platform for Monovalent Ni Chemistry
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-14 DOI: 10.1021/acs.organomet.4c0045010.1021/acs.organomet.4c00450
Li Gu,  and , Alex McSkimming*, 
{"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 Ni<sup>2+</sup> complexes supported by less bulky heteroscorpionates led to a thermally unstable Ni<sup>+</sup> species that could be trapped as the corresponding PPh<sub>3</sub> adduct. In situ reaction of the aforementioned Ni<sup>+</sup> complex with a bulky aryl azide affords a transient Ni<sup>3+</sup> imide, for which attack of the C donor at the N<sub>imido</sub> atom, followed by rapid isomerization, furnishes a three-coordinate Ni<sup>+</sup> 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 Ph<sub>2</sub>(CH<sub>3</sub>)C– substituents was able to support a thermally stable, isolable Ni<sup>+</sup> complex, in which a phenyl group of one Ph<sub>2</sub>(CH<sub>3</sub>)C– unit binds Ni in an η<sup>2</sup> fashion. This complex proved to be relatively unreactive toward organic azides. The labile C donor in the former Ni<sup>+</sup> complex could be trapped via the addition of B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>, affording a zwitterionic Ni<sup>+</sup> complex. All Ni<sup>+</sup> 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}
引用次数: 0
Back with the Flash Communication
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-13 DOI: 10.1021/acs.organomet.4c0049710.1021/acs.organomet.4c00497
Paul J. Chirik*, 
{"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}
引用次数: 0
Understanding the Ligand Influence in the Multistep Reaction of Diazoalkanes with Palladium Complexes Leading to Carbene-Aryl Coupling.
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-10 eCollection Date: 2025-01-27 DOI: 10.1021/acs.organomet.4c00439
Francisco Villalba, Ana C Albéniz
{"title":"Understanding the Ligand Influence in the Multistep Reaction of Diazoalkanes with Palladium Complexes Leading to Carbene-Aryl Coupling.","authors":"Francisco Villalba, Ana C Albéniz","doi":"10.1021/acs.organomet.4c00439","DOIUrl":"10.1021/acs.organomet.4c00439","url":null,"abstract":"<p><p>The reaction of diphosphino aryl complexes [Pd(C<sub>6</sub>F<sub>5</sub>)(L-L)(NCMe)](BF<sub>4</sub>) (L-L = dppe, dppp, dppb) with diazoalkanes N<sub>2</sub>CHR (<i>R</i> = -CH=CHPh, Ph) leads to η<sup>3</sup>-allyl or η<sup>3</sup>-benzyl palladium derivatives that are the organometallic products resulting from carbene-aryl coupling. The experimental trend shows that the reaction is favored for dppe > dppp > dppb. It involves several consecutive steps, i.e., diazoalkane coordination, nitrogen extrusion to give a Pd-carbene, and migratory insertion, which are experimentally inseparable, but they can be studied with the help of DFT calculations. The bulkiness and bite angle of the ligand exert a large influence in the relative rate of the steps involved in the reaction, and we have found that carbene formation by N<sub>2</sub> extrusion is the step with the largest barrier for dppe. In contrast, the coordination of the diazoalkane is the most energy-demanding step for the larger dppp and dppb diphosphines. Thus, ligand substitution controls the rate, an important elemental step rarely considered in mechanistic studies of carbene cross coupling reactions. Since diazoalkanes are the most common carbene precursors, either directly or generated from hydrazones, the choice of ligand can be very important to facilitate the entrance of the carbene precursor in the catalytic cycle.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"394-402"},"PeriodicalIF":2.5,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11776105/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143062415","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}
引用次数: 0
Understanding the Ligand Influence in the Multistep Reaction of Diazoalkanes with Palladium Complexes Leading to Carbene-Aryl Coupling
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-10 DOI: 10.1021/acs.organomet.4c0043910.1021/acs.organomet.4c00439
Francisco Villalba,  and , Ana C. Albéniz*, 
{"title":"Understanding the Ligand Influence in the Multistep Reaction of Diazoalkanes with Palladium Complexes Leading to Carbene-Aryl Coupling","authors":"Francisco Villalba,&nbsp; and ,&nbsp;Ana C. Albéniz*,&nbsp;","doi":"10.1021/acs.organomet.4c0043910.1021/acs.organomet.4c00439","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00439https://doi.org/10.1021/acs.organomet.4c00439","url":null,"abstract":"<p >The reaction of diphosphino aryl complexes [Pd(C<sub>6</sub>F<sub>5</sub>)(L-L)(NCMe)](BF<sub>4</sub>) (L-L = dppe, dppp, dppb) with diazoalkanes N<sub>2</sub>CHR (<i>R</i> = −CH═CHPh, Ph) leads to η<sup>3</sup>-allyl or η<sup>3</sup>-benzyl palladium derivatives that are the organometallic products resulting from carbene-aryl coupling. The experimental trend shows that the reaction is favored for dppe &gt; dppp &gt; dppb. It involves several consecutive steps, i.e., diazoalkane coordination, nitrogen extrusion to give a Pd-carbene, and migratory insertion, which are experimentally inseparable, but they can be studied with the help of DFT calculations. The bulkiness and bite angle of the ligand exert a large influence in the relative rate of the steps involved in the reaction, and we have found that carbene formation by N<sub>2</sub> extrusion is the step with the largest barrier for dppe. In contrast, the coordination of the diazoalkane is the most energy-demanding step for the larger dppp and dppb diphosphines. Thus, ligand substitution controls the rate, an important elemental step rarely considered in mechanistic studies of carbene cross coupling reactions. Since diazoalkanes are the most common carbene precursors, either directly or generated from hydrazones, the choice of ligand can be very important to facilitate the entrance of the carbene precursor in the catalytic cycle.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"394–402 394–402"},"PeriodicalIF":2.5,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00439","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143088091","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}
引用次数: 0
Neptunium Pyridine Dipyrrolide Complexes
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-09 DOI: 10.1021/acs.organomet.4c0047210.1021/acs.organomet.4c00472
Leyla R. Valerio, Andrew W. Mitchell, Lauren M. Lopez, Matthias Zeller, Suzanne C. Bart* and Ellen M. Matson*, 
{"title":"Neptunium Pyridine Dipyrrolide Complexes","authors":"Leyla R. Valerio,&nbsp;Andrew W. Mitchell,&nbsp;Lauren M. Lopez,&nbsp;Matthias Zeller,&nbsp;Suzanne C. Bart* and Ellen M. Matson*,&nbsp;","doi":"10.1021/acs.organomet.4c0047210.1021/acs.organomet.4c00472","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00472https://doi.org/10.1021/acs.organomet.4c00472","url":null,"abstract":"<p >Two pyridine dipyrrolide neptunium(IV) complexes, (<sup>Mes</sup>PDP<sup>Ph</sup>)NpCl<sub>2</sub>(THF) and Np(<sup>Mes</sup>PDP<sup>Ph</sup>)<sub>2</sub>, where (<sup>Mes</sup>PDP<sup>Ph</sup>)<sup>2–</sup> is the doubly deprotonated form of 2,6-bis(5-(2,4,6-trimethylphenyl)-3-phenyl-1<i>H</i>-pyrrol-2-yl)pyridine, have been prepared. Characterization of the complexes has been performed through a combination of solid- and solution-state methods, including single-crystal X-ray diffraction and electronic absorption and nuclear magnetic resonance spectroscopies. Collectively, these data confirm the formation of the mono- and bis-ligated species. Electrochemistry of a series of bis-ligated actinide complexes, An(<sup>Mes</sup>PDP<sup>Ph</sup>)<sub>2</sub> (An = Th, U, Np), is presented.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"439–446 439–446"},"PeriodicalIF":2.5,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00472","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091301","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}
引用次数: 0
Divergent Reactivity of Azides and Diazoalkanes Toward Ferrous Complexes and Isolation of a FeIII Carbene Radical Complex
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-09 DOI: 10.1021/acs.organomet.4c0047110.1021/acs.organomet.4c00471
Ethan Zars, Lisa Pick, Achala Kankanamge, Michael R. Gau, Patrick J. Carroll, Samantha N. MacMillan, Kyle M. Lancaster*, Karsten Meyer* and Daniel J. Mindiola*, 
{"title":"Divergent Reactivity of Azides and Diazoalkanes Toward Ferrous Complexes and Isolation of a FeIII Carbene Radical Complex","authors":"Ethan Zars,&nbsp;Lisa Pick,&nbsp;Achala Kankanamge,&nbsp;Michael R. Gau,&nbsp;Patrick J. Carroll,&nbsp;Samantha N. MacMillan,&nbsp;Kyle M. Lancaster*,&nbsp;Karsten Meyer* and Daniel J. Mindiola*,&nbsp;","doi":"10.1021/acs.organomet.4c0047110.1021/acs.organomet.4c00471","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00471https://doi.org/10.1021/acs.organomet.4c00471","url":null,"abstract":"<p >Treatment of [(<sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr)Fe(OEt<sub>2</sub>)] (<b>1</b>-OEt<sub>2</sub>) (<sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr<sup>2–</sup> = 3,5-<sup><i>t</i></sup>Bu<sub>2</sub>-bis(pyrrolyl)pyridine) with trimethylsilyl azide (N<sub>3</sub>SiMe<sub>3</sub>) and subsequent photolysis at 390 nm results in clean formation of [(<sup><i>t</i>Bu</sup>pyrrpyrpyrrNHSiMe<sub>3</sub>)Fe] (<b>2</b>) as the result of a nitrene being inserted into a <i>tert</i>-butyl C–H bond of the <sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr ligand. Treatment of <b>1</b>-OEt<sub>2</sub> with azidotrimethyltin (N<sub>3</sub>SnMe<sub>3</sub>), however, results in isolation of the γ-bound azide adduct ferrous complex, [(<sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr)Fe(N<sub>3</sub>SnMe<sub>3</sub>)] (<b>1</b>-N<sub>3</sub>SnMe<sub>3</sub>). When treated with diphenyl diazomethane (Ph<sub>2</sub>CN<sub>2</sub>), complex <b>1</b>-OEt<sub>2</sub> converts to the iron carbene complex [(<sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr)FeCPh<sub>2</sub>] (<b>1</b>-CPh<sub>2</sub>), and the X-ray structure revealed a Fe–CPh<sub>2</sub> bond length of 1.964(3) Å. A room temperature magnetic moment of <b>1</b>-CPh<sub>2</sub> indicates an <i>S</i> = 2 spin state, consistent with a high-spin Fe<sup>III</sup> center antiferromagnetically coupled to a carbene radical anion (CPh<sub>2</sub><sup>•–</sup>). Zero-field <sup>57</sup>Fe Mössbauer spectroscopy and Fe K-edge X-ray absorption spectroscopy confirm this assignment. In solution, complex <b>1</b>-CPh<sub>2</sub> rearranges to [{<sup><i>t</i>Bu</sup>pyrrpyrC(═CPh<sub>2</sub>)-C(CMe<sub>3</sub>)═CH–C(CMe<sub>3</sub>)═N}Fe]<sub>2</sub> (<b>3</b>) resulting from carbene insertion into the 1-position of the pyrrolide arm of the <sup><i>t</i>Bu</sup>pyrr<sub>2</sub>pyr ligand and dimerization. Complex <b>3</b> possesses two high-spin Fe<sup>II</sup> centers according to <sup>57</sup>Fe Mössbauer spectroscopy, with antiferromagnetic coupling between the spin centers. Monitoring the conversion of <b>1</b>-CPh<sub>2</sub> to <b>3</b> by UV–vis spectroscopy reveals this process to be first order in <b>1</b>-CPh<sub>2</sub> with a highly ordered transition state evidenced by activation parameters: Δ<i>S</i><sup>‡</sup> = −87.6 ± 25.8 J·mol<sup>–1</sup>·K<sup>–1</sup> and Δ<i>H</i><sup>‡</sup> = 63.1 ± 8.3 kJ·mol<sup>–1</sup>.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"427–438 427–438"},"PeriodicalIF":2.5,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091576","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}
引用次数: 0
Neptunium Pyridine Dipyrrolide Complexes.
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-09 eCollection Date: 2025-01-27 DOI: 10.1021/acs.organomet.4c00472
Leyla R Valerio, Andrew W Mitchell, Lauren M Lopez, Matthias Zeller, Suzanne C Bart, Ellen M Matson
{"title":"Neptunium Pyridine Dipyrrolide Complexes.","authors":"Leyla R Valerio, Andrew W Mitchell, Lauren M Lopez, Matthias Zeller, Suzanne C Bart, Ellen M Matson","doi":"10.1021/acs.organomet.4c00472","DOIUrl":"10.1021/acs.organomet.4c00472","url":null,"abstract":"<p><p>Two pyridine dipyrrolide neptunium(IV) complexes, (<sup>Mes</sup>PDP<sup>Ph</sup>)NpCl<sub>2</sub>(THF) and Np(<sup>Mes</sup>PDP<sup>Ph</sup>)<sub>2</sub>, where (<sup>Mes</sup>PDP<sup>Ph</sup>)<sup>2-</sup> is the doubly deprotonated form of 2,6-bis(5-(2,4,6-trimethylphenyl)-3-phenyl-1<i>H</i>-pyrrol-2-yl)pyridine, have been prepared. Characterization of the complexes has been performed through a combination of solid- and solution-state methods, including single-crystal X-ray diffraction and electronic absorption and nuclear magnetic resonance spectroscopies. Collectively, these data confirm the formation of the mono- and bis-ligated species. Electrochemistry of a series of bis-ligated actinide complexes, An(<sup>Mes</sup>PDP<sup>Ph</sup>)<sub>2</sub> (An = Th, U, Np), is presented.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"439-446"},"PeriodicalIF":2.5,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11776103/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143062412","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}
引用次数: 0
Zerovalent Triphosphine Ruthenium Complexes for Coupling Carbon Dioxide and Ethylene
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-08 DOI: 10.1021/acs.organomet.4c0043310.1021/acs.organomet.4c00433
Tristan T. Adamson, Laura G. Reeder, Steven P. Kelley and Wesley H. Bernskoetter*, 
{"title":"Zerovalent Triphosphine Ruthenium Complexes for Coupling Carbon Dioxide and Ethylene","authors":"Tristan T. Adamson,&nbsp;Laura G. Reeder,&nbsp;Steven P. Kelley and Wesley H. Bernskoetter*,&nbsp;","doi":"10.1021/acs.organomet.4c0043310.1021/acs.organomet.4c00433","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00433https://doi.org/10.1021/acs.organomet.4c00433","url":null,"abstract":"<p >The coupling of carbon dioxide and ethylene to generate value-added chemicals has been part of recent fundamental advances to improve sustainability in commercial chemical synthons. A formal zerovalent triphosphine-ligated ruthenium complex, (<sup><i>t</i></sup>BuP(CH<sub>2</sub>CH<sub>2</sub>PEt<sub>2</sub>)<sub>2</sub>)Ru(κ-<i>S</i>-DMSO)(C<sub>2</sub>H<sub>4</sub>), was found to promote CO<sub>2</sub> functionalization, affording products derived from both a 1:1 and 1:2 ethylene to CO<sub>2</sub> coupling stoichiometry. The equimolecular coupling reaction selectively afforded a five-membered ruthenium lactone species, (<sup><i>t</i></sup>BuP(CH<sub>2</sub>CH<sub>2</sub>PEt<sub>2</sub>)<sub>2</sub>)Ru(κ-<i>S</i>-DMSO)(κ-<i>C</i>,κ-<i>O</i>-CH<sub>2</sub>CH<sub>2</sub>CO<sub>2</sub>), under low CO<sub>2</sub> pressure. At higher CO<sub>2</sub> pressure, the ruthenium lactone complex activated a second equivalent of CO<sub>2</sub>, yielding a dimeric methylmalonate ruthenium compound, [(<sup><i>t</i></sup>BuP(CH<sub>2</sub>CH<sub>2</sub>PEt<sub>2</sub>)<sub>2</sub>)Ru(μ<sub>2</sub>, κ<sup>1</sup>-<i>O</i>, κ<sup>2</sup>-<i>O</i>,<i>O</i>-O<sub>2</sub>CCHCH<sub>3</sub>CO<sub>2</sub>)]<sub>2</sub>. Both carbon dioxide activation products were characterized by X-ray diffraction. Preliminary mechanistic studies suggest that reversible β-H elimination is a key process in the conversion between the two ruthenium carboxylate species. A rare, formally zerovalent ruthenium coordination compound stabilized only by ethylene and DMSO ligands was also isolated and characterized.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"385–393 385–393"},"PeriodicalIF":2.5,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143091125","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}
引用次数: 0
Theoretical Insight into Cp*Ir-Catalyzed Upgrading of Ethanol to n-Butanol: The Crucial Role of Cs2CO3
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-07 DOI: 10.1021/acs.organomet.4c0044610.1021/acs.organomet.4c00446
Linlin Yang, Cheng Zhang, Yingzhi Ren, Zhao-Xu Chen* and Guixiang Zeng*, 
{"title":"Theoretical Insight into Cp*Ir-Catalyzed Upgrading of Ethanol to n-Butanol: The Crucial Role of Cs2CO3","authors":"Linlin Yang,&nbsp;Cheng Zhang,&nbsp;Yingzhi Ren,&nbsp;Zhao-Xu Chen* and Guixiang Zeng*,&nbsp;","doi":"10.1021/acs.organomet.4c0044610.1021/acs.organomet.4c00446","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00446https://doi.org/10.1021/acs.organomet.4c00446","url":null,"abstract":"<p >The ethanol-to-<i>n</i>-butanol upgrading process catalyzed by a Cp*Ir complex (<b>1-Ir</b>) and mild base Cs<sub>2</sub>CO<sub>3</sub> was investigated using density functional theory calculations. Initially, Cs<sub>2</sub>CO<sub>3</sub> and <b>1-Ir</b> form an active species <b>2</b> with an exothermicity of 12.9 kcal/mol. Ethanol dehydrogenation then occurs through the cooperation of the Ir center and Cs<sub>2</sub>CO<sub>3</sub> to produce an Ir–H complex <b>3</b> with the release of acetaldehyde and CsHCO<sub>3</sub>. Cs<sub>2</sub>CO<sub>3</sub> catalyzes the aldol condensation of acetaldehyde to produce a C<sub>4</sub> intermediate crotonaldehyde. Subsequently, the successive hydride and proton migrations occur from <b>3</b> and ethanol to crotonaldehyde, respectively, to produce butanal. The proton migration step is the rate-determining step (Δ<i>G</i><sup>‡</sup>/Δ<i>G</i> = 29.1/–12.1 kcal/mol). Finally, <i>n</i>-butanol is produced via transfer hydrogenation of butanal with ethanol catalyzed by Cs<sub>2</sub>CO<sub>3</sub>. High selectivity for <i>n</i>-butanol is due to preferential hydrogenation of crotonaldehyde over its further condensation into C<sub>6</sub> species. Cs<sub>2</sub>CO<sub>3</sub> plays a critical role in promoting ethanol dehydrogenation, aldol condensation, and butanal hydrogenation. In contrast, Na<sub>2</sub>CO<sub>3</sub> significantly reduces reaction efficiency mainly due to its weaker basicity in the aldol condensation of acetaldehyde. These findings provide insights into the ethanol-to-<i>n</i>-butanol conversion and offer a foundation for developing milder bases for the reaction.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 2","pages":"410–417 410–417"},"PeriodicalIF":2.5,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143090924","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}
引用次数: 0
Bis(Tetrathiafulvalenes) with Mixed Phosphine and Silane Double Bridges
IF 2.5 3区 化学
Organometallics Pub Date : 2025-01-07 DOI: 10.1021/acs.organomet.4c0032010.1021/acs.organomet.4c00320
Axel Houssin, Ion Danila, Frédéric Biaso, Magali Allain, Michel Geoffroy, Flavia Pop, Marco Caricato and Narcis Avarvari*, 
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