Organometallics最新文献

{"title":"2,4,6-Triphenylpyridinium-Substituted Neutral Nickel Catalysts: Ethylene Polymerization, Influence of Activator, Catalyst Decomposition, and End-Group Analysis","authors":"Mateusz Janeta,&nbsp;Alberto Feliciano Carmona,&nbsp;Xiqu Wang,&nbsp;Maurice Brookhart* and Olafs Daugulis*,&nbsp;","doi":"10.1021/acs.organomet.4c0051210.1021/acs.organomet.4c00512","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00512https://doi.org/10.1021/acs.organomet.4c00512","url":null,"abstract":"<p >The reactivity of 2,4,6-triphenylpyridinium-substituted nickel(II)-salicyliminato catalysts in ethylene polymerization has been explored. The known catalyst <b>6a</b> equipped with a 2,6-diisopropylphenyl group affords polyethylene with <i>M</i>_n = 10–12 kDa at 19 °C, while <b>8a</b> possessing the bulkier 2,6-diphenylphenyl moiety gives polymer with <i>M</i>_n = 270–310 kDa. The stability of catalyst <b>6a</b> depends on the borane as activator. If B(C₆F₅)₃ is employed, enhanced stability is observed compared with that using 3H₂O·B(C₆F₅)₃ activator. Catalyst <b>6a</b> decomposes to form a hydroxyl-bridged dimer <b>14</b> which may be reactivated, albeit inefficiently, by an excess borane activator. The polymer formed by <b>6a</b> contains ca. 3–6% of 2-trifluoromethylphenyl, pentafluorophenyl, and 3,5-bis(trifluoromethyl)phenyl end groups combined. The pentafluorophenyl end group originates from the reaction of <b>6a</b> with the borane activator and from the reactivation of hydroxyl-bridged dimer <b>14</b>. 3,5-Bis(trifluoromethyl)phenyl end groups are likely formed in a reaction sequence initiated by the protonation of one aryl group in NaBArF that creates B[C₆H₃(CF₃)₂]₃. The triarylborane can then react with <b>6a</b> or <b>14</b>, transferring the 3,5-bis(trifluoromethyl)phenyl group to nickel.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"672–683 672–683"},"PeriodicalIF":2.5,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576510","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":"The π-Annulated Carbene 1,3-Di-iso-propylbenzimidazolin-2-ylidene (BIiPr) and Its Application in Nickel(0) Chemistry","authors":"Martin S. Luff,&nbsp;Celine S. Corsei and Udo Radius*,&nbsp;","doi":"10.1021/acs.organomet.5c0001510.1021/acs.organomet.5c00015","DOIUrl":"https://doi.org/10.1021/acs.organomet.5c00015https://doi.org/10.1021/acs.organomet.5c00015","url":null,"abstract":"<p >The stereoelectronic parameters of the π-annulated carbene 1,3-di-<i>iso</i>-propylbenzimidazolin-2-ylidene (BI<i>i</i>Pr) were evaluated in this study. The <i>N</i>-<i>iso</i>-propyl substituents and the additional π-backbone of BI<i>i</i>Pr lead to a moderate steric bulk, which lies in between that of the backbone unsubstituted carbene I<i>i</i>Pr and its backbone methylated congener I<i>i</i>Pr^Me (IR = 1,3-diorganylimidazolin-2-ylidene; IR^Me = 1,3-diorganyl-4,5-dimethylimidazolin-2-ylidene). While the net electron donation properties of BI<i>i</i>Pr are slightly lower than those of I<i>i</i>Pr and I<i>i</i>Pr^Me, its π-acidity is significantly higher and lies between that of imidazole-based NHCs and cAACs. These unique stereoelectronic properties led to distinctly different reactivities with Ni(0) reagents in comparison to I<i>i</i>Pr and I<i>i</i>Pr^Me. The reaction of BI<i>i</i>Pr with [Ni(COD)₂] afforded homoleptic three-coordinated [Ni(BI<i>i</i>Pr)₃] (<b>1</b>) and the olefin complex [Ni₂(BI<i>i</i>Pr)₄(μ²-(η²:η²)-COD)] (<b>2</b>) only as a side product. The reaction of BI<i>i</i>Pr with [Ni(CO)₄] yielded [Ni(BI<i>i</i>Pr)₂(CO)₂] (<b>3</b>), which was employed as a starting material for the facile synthesis of the uncapped, NHC-ligated nickel <i>Chini</i>-cluster analog [Ni₃(BI<i>i</i>Pr)₃(μ²-CO)₃] (<b>4</b>). This cluster was synthesized from the reaction of <b>3</b> with [Ni(COD)₂]. These results demonstrate the unique stereoelectronic properties of BI<i>i</i>Pr and reveal the influence of small variations of the substitutional pattern of NHCs on the stabilities and reactivities of transition metal complexes.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"691–703 691–703"},"PeriodicalIF":2.5,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576606","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":"Catalyst Activation and Speciation Involving DyadPalladate Precatalysts in Suzuki–Miyaura and Buchwald–Hartwig Cross-Couplings","authors":"Neil W. J. Scott,&nbsp;Paula Chirila,&nbsp;Christopher S. Horbaczewskyj,&nbsp;Eric D. Slack,&nbsp;Adrian C. Whitwood and Ian J. S. Fairlamb*,&nbsp;","doi":"10.1021/acs.organomet.4c0048610.1021/acs.organomet.4c00486","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00486https://doi.org/10.1021/acs.organomet.4c00486","url":null,"abstract":"<p >Understanding mechanisms underpinning Pd precatalyst activation and formation of active species is important in maximizing catalyst activity and lifetime. DyadPalladate precatalysts, represented by the general formula [R₃PH⁺]₂[Pd₂Cl₆]^2– (R₃P = tertiary alkylphosphine/arylphosphines), have recently emerged as sustainable, active Pd precatalysts for cross-couplings (e.g., Suzuki–Miyaura {SMCC} and Buchwald–Hartwig aryl amination {BHA}). This study investigates the activation of the [HXPhos]₂[Pd₂Cl₆] <b>1</b>, as a model precatalyst from the DyadPalladate class, against BHA and SMCC reactions. It was found that BHA and SMCC reactions reached the same active Pd⁰ catalyst, [Pd⁰(XPhos)₂]. This species is generated efficiently through a reductive activation step involving a dual base/nucleophile chemical trigger. However, the mechanistic path of each is somewhat different based on the selected nucleophile. The active Pd complex participates in oxidative addition with aryl halides, the first committed step in many cross-coupling reactions. The activation pathway and catalytic efficiency of [HXPhos]₂[Pd₂Cl₆] <b>1</b> were compared with those of known Pd^II precatalysts, possessing the XPhos ligand, through both stoichiometric and catalytic studies. Investigating the activation triggers and characterizing the active Pd⁰ catalyst, under catalytically relevant conditions, provide valuable insight into future catalyst design, targeting optimal efficiency in specific reactions, <i>i.e</i>., knowing that the precatalyst has been fully activated.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"654–664 654–664"},"PeriodicalIF":2.5,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00486","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576730","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":"Catalyst Activation and Speciation Involving DyadPalladate Precatalysts in Suzuki-Miyaura and Buchwald-Hartwig Cross-Couplings.","authors":"Neil W J Scott, Paula Chirila, Christopher S Horbaczewskyj, Eric D Slack, Adrian C Whitwood, Ian J S Fairlamb","doi":"10.1021/acs.organomet.4c00486","DOIUrl":"10.1021/acs.organomet.4c00486","url":null,"abstract":"<p><p>Understanding mechanisms underpinning Pd precatalyst activation and formation of active species is important in maximizing catalyst activity and lifetime. DyadPalladate precatalysts, represented by the general formula [R₃PH⁺]₂[Pd₂Cl₆]^2- (R₃P = tertiary alkylphosphine/arylphosphines), have recently emerged as sustainable, active Pd precatalysts for cross-couplings (e.g., Suzuki-Miyaura {SMCC} and Buchwald-Hartwig aryl amination {BHA}). This study investigates the activation of the [HXPhos]₂[Pd₂Cl₆] <b>1</b>, as a model precatalyst from the DyadPalladate class, against BHA and SMCC reactions. It was found that BHA and SMCC reactions reached the same active Pd⁰ catalyst, [Pd⁰(XPhos)₂]. This species is generated efficiently through a reductive activation step involving a dual base/nucleophile chemical trigger. However, the mechanistic path of each is somewhat different based on the selected nucleophile. The active Pd complex participates in oxidative addition with aryl halides, the first committed step in many cross-coupling reactions. The activation pathway and catalytic efficiency of [HXPhos]₂[Pd₂Cl₆] <b>1</b> were compared with those of known Pd^II precatalysts, possessing the XPhos ligand, through both stoichiometric and catalytic studies. Investigating the activation triggers and characterizing the active Pd⁰ catalyst, under catalytically relevant conditions, provide valuable insight into future catalyst design, targeting optimal efficiency in specific reactions, <i>i.e</i>., knowing that the precatalyst has been fully activated.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"654-664"},"PeriodicalIF":2.5,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11898177/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622886","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":"Multigram-Scale Synthetic Routes to Solvent-Free Common Secondary Dialkylphosphines and Chlorodialkylphosphines","authors":"Amanda A. Fogh,&nbsp;Sara Belazregue,&nbsp;Andrew E. Ashley* and F. Mark Chadwick*,&nbsp;","doi":"10.1021/acs.organomet.4c0050810.1021/acs.organomet.4c00508","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00508https://doi.org/10.1021/acs.organomet.4c00508","url":null,"abstract":"<p >Secondary dialkylphosphines and chlorodialkylphosphines are some of the most common starting points in ligand synthesis; however, sourcing these synthons can be troublesome. In this paper, we present scalable synthetic routes to the <i>iso</i>-propyl, <i>tert</i>-butyl, and cyclohexyl derivatives. Detailed experimental procedures are given to allow for ease of synthesis.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"665–671 665–671"},"PeriodicalIF":2.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00508","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576507","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":"Mechanistic Studies of Alkyl Chloride Acetoxylation by Pt-Sb Complexes.","authors":"Christopher K Webber, Jugal Kumawat, Fanji Kong, Diane A Dickie, Daniel H Ess, T Brent Gunnoe","doi":"10.1021/acs.organomet.4c00399","DOIUrl":"10.1021/acs.organomet.4c00399","url":null,"abstract":"<p><p>The bis-acetate complexes (SbQ₃)Pt(OAc)₂ (<b>1</b>) and (SbQ₂Ph)Pt(OAc)₂ (<b>2</b>) (Q = 8-quinolinyl) were used to study C-Cl acetoxylation of 1,2-dichloroethane (DCE) to generate 2-chloroethyl acetate and the complexes (SbQ₃)PtCl₂ (<b>1b</b>) and (SbQ₂Ph)PtCl₂ (<b>2b</b>), respectively. The first acetoxylation step produced the intermediates (SbQ₃)Pt(Cl)(OAc) (<b>1a</b>) and (SbQ₂Ph)Pt(Cl)(OAc) (<b>2a</b>). The reaction was studied using pseudo first order kinetics (excess DCE) in order to compare the rates of reaction of <b>1</b> and <b>2</b>, which revealed that <i>k</i> _obs = 2.44(6) × 10^-4 s^-1 for <b>1</b> and 0.51(2) × 10^-4 s^-1 for <b>2</b>. The intermediate <b>1a</b> was synthesized independently, and the solid-state structure was determined using single crystal X-ray diffraction. A non-Sb containing control complex, (^tbpy)Pt(OAc)₂ (<b>3</b>) (^tbpy = 4,4'-di-<i>tert</i>-butyl-2,2'bipyridine), was studied for the acetoxylation of DCE to form (^tbpy)Pt(Cl)(OAc) with <i>k</i> _obs = 0.46(1) × 10^-4 s^-1. Density Functional Theory (DFT) calculations were used to examine possible Pt-mediated mechanisms for the reactions of <b>1</b>, <b>2</b>, or <b>3</b> with DCE. The lowest energy calculated substitution mechanism occurs with nucleophilic attack by the Pt center on the C-Cl bond followed acetate reaction with the Pt-C bond. However, close in energy and potentially also a viable mechanism is a direct substitution mechanism where the coordinated acetate anion directly reacts with the C-Cl bond of DCE. In addition, the rate of acetoxylation for complex <b>1</b> in heated dichloromethane-<i>d</i> ₂ and chloroform-<i>d</i> was determined (0.43(1) × 10^-4 s^-1 for dichloromethane-<i>d</i> ₂ and 0.37(1) × 10^-4 s^-1 for chloroform-<i>d</i>) and compared to the rate of acetoxylation of DCE.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"617-627"},"PeriodicalIF":2.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11898169/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622887","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":"Mechanistic Studies of Alkyl Chloride Acetoxylation by Pt–Sb Complexes","authors":"Christopher K. Webber,&nbsp;Jugal Kumawat,&nbsp;Fanji Kong,&nbsp;Diane A. Dickie,&nbsp;Daniel H. Ess* and T. Brent Gunnoe*,&nbsp;","doi":"10.1021/acs.organomet.4c0039910.1021/acs.organomet.4c00399","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00399https://doi.org/10.1021/acs.organomet.4c00399","url":null,"abstract":"<p >The bis-acetate complexes (SbQ₃)Pt(OAc)₂ (<b>1</b>) and (SbQ₂Ph)Pt(OAc)₂ (<b>2</b>) (Q = 8-quinolinyl) were used to study C–Cl acetoxylation of 1,2-dichloroethane (DCE) to generate 2-chloroethyl acetate and the complexes (SbQ₃)PtCl₂ (<b>1b</b>) and (SbQ₂Ph)PtCl₂ (<b>2b</b>), respectively. The first acetoxylation step produced the intermediates (SbQ₃)Pt(Cl)(OAc) (<b>1a</b>) and (SbQ₂Ph)Pt(Cl)(OAc) (<b>2a</b>). The reaction was studied using pseudo first order kinetics (excess DCE) in order to compare the rates of reaction of <b>1</b> and <b>2</b>, which revealed that <i>k</i>_obs = 2.44(6) × 10^–4 s^–1 for <b>1</b> and 0.51(2) × 10^–4 s^–1 for <b>2</b>. The intermediate <b>1a</b> was synthesized independently, and the solid-state structure was determined using single crystal X-ray diffraction. A non-Sb containing control complex, (^tbpy)Pt(OAc)₂ (<b>3</b>) (^tbpy = 4,4′-di-<i>tert</i>-butyl-2,2′bipyridine), was studied for the acetoxylation of DCE to form (^tbpy)Pt(Cl)(OAc) with <i>k</i>_obs = 0.46(1) × 10^–4 s^–1. Density Functional Theory (DFT) calculations were used to examine possible Pt-mediated mechanisms for the reactions of <b>1</b>, <b>2</b>, or <b>3</b> with DCE. The lowest energy calculated substitution mechanism occurs with nucleophilic attack by the Pt center on the C−Cl bond followed acetate reaction with the Pt−C bond. However, close in energy and potentially also a viable mechanism is a direct substitution mechanism where the coordinated acetate anion directly reacts with the C−Cl bond of DCE. In addition, the rate of acetoxylation for complex <b>1</b> in heated dichloromethane-<i>d</i>₂ and chloroform-<i>d</i> was determined (0.43(1) × 10^–4 s^–1 for dichloromethane-<i>d</i>₂ and 0.37(1) × 10^–4 s^–1 for chloroform-<i>d</i>) and compared to the rate of acetoxylation of DCE.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"617–627 617–627"},"PeriodicalIF":2.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.organomet.4c00399","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576502","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":"Reductive Coupling of Carbon Monoxide by an Anionic Calcium Hydride: A Computational Mechanistic Study","authors":"Alireza Ariafard*,&nbsp;Farshad Shiri,&nbsp;Robert Stranger,&nbsp;Liesa Eickhoff* and Jamie Hicks*,&nbsp;","doi":"10.1021/acs.organomet.4c0046410.1021/acs.organomet.4c00464","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00464https://doi.org/10.1021/acs.organomet.4c00464","url":null,"abstract":"<p >We recently reported that a dimeric, anionic calcium hydride complex can perform the selective reduction and C–C coupling of carbon monoxide. Here, the mechanism of this reaction is investigated computationally. Stepwise coordination and reduction of CO is calculated, with the first molecule of CO being transformed into a Ca-bound formyl ligand. Subsequently, a second CO molecule coordinates to the same calcium center, and C–C bond formation proceeds via insertion of this second CO molecule into the Ca–C^formyl bond. This is in contrast to mechanisms reported for CO reduction with dimeric neutral and cationic Group 2 molecular hydrides, in which both Group 2 centers are involved in this key C–C bond-forming step. In a final step, the remaining hydride ligand located on the second calcium center is transferred to the newly formed CO-derived ligand, yielding a <i>cis</i>-ethenediolate unit, the single experimentally observed product. The <i>cis</i> selectivity can be explained by electrostatic repulsion in the pathway to the <i>trans</i> isomer. NBO/NLMO and energy decomposition analyses show that, in general, electrostatic interactions dominate the interaction between the CO-derived ligands and the calcium center.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"637–645 637–645"},"PeriodicalIF":2.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576518","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":"Potassium Isopropyl(trimethylsilyl)amide and Potassium tert-Butyl(trimethylsilyl)amide: Solvent-Dependent Solution Structures and Reactivities","authors":"Jesse A. Spivey,&nbsp; and ,&nbsp;David B. Collum*,&nbsp;","doi":"10.1021/acs.organomet.5c0001310.1021/acs.organomet.5c00013","DOIUrl":"https://doi.org/10.1021/acs.organomet.5c00013https://doi.org/10.1021/acs.organomet.5c00013","url":null,"abstract":"<p >Potassium isopropyl(trimethylsilyl)amide (KPTA) and potassium <i>tert</i>-butyl(trimethylsilyl)amide (KBTA) were prepared as stable 1.0 M stock solutions in Et₃N or isolable crystalline solids. A combination of the method of continuous variations and a heavy reliance on ²⁹Si NMR spectroscopy revealed solvent-dependent dimers and monomers. DFT computations offered insights into the solvation. Weakly coordinating solvents such as toluene and triethylamine afford dimers. In THF, KPTA is dimeric, whereas KBTA is dimeric at low THF concentration and monomeric in neat THF. Chronic and often poorly understood loss of the ²⁹Si resonance made a broadly based, systematic study difficult and may have obscured deaggregation or ionization. Reactivity was probed using orthometallations by KBTA, which pressed the limits of its basicity and probably impacted the yields in some cases.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"684–690 684–690"},"PeriodicalIF":2.5,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576649","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":"Simultaneous Back-and-Forth Dual Reflux Apparatus for Complete Removal of Water and Alcohol in Equilibrium Systems","authors":"Ju Yong Park,&nbsp;Hye In Seo,&nbsp;Hyeon Jeong Seo,&nbsp;Sangdeok Seo,&nbsp;Hyunjin Kim,&nbsp;Sang Uk Park and Bun Yeoul Lee*,&nbsp;","doi":"10.1021/acs.organomet.4c0048110.1021/acs.organomet.4c00481","DOIUrl":"https://doi.org/10.1021/acs.organomet.4c00481https://doi.org/10.1021/acs.organomet.4c00481","url":null,"abstract":"<p >Many chemical reactions generate alcohol or water as byproducts under equilibrium conditions. For complete conversion, it is necessary to remove these protic byproducts entirely from the equilibrium system, which can often be challenging. To address this issue, we developed an “simultaneous back-and-forth dual reflux apparatus” consisting of two reactors (Reactor A and B), each connected to a separate condenser (Condenser A and B). The key feature of this design is that the liquid condensed in Condenser A is returned to Reactor B, while the liquid condensed in Condenser B is returned to Reactor A. Using this apparatus, [Cr(EtOH)₄Cl₂][B(C₆F₅)₄] was efficiently converted on a large scale to [CrCl₂][B(C₆F₅)₄]·6.5(CH₃CN). In this reaction, the EtOH formed in Reactor A was transferred, along with CH₃CN serving as both solvent and reactant, via Condenser A to Reactor B containing (iBu)₃Al in CH₃CN, where the transferred EtOH was destroyed. The versatility of this apparatus was demonstrated in the conversion of various hydrated metal complexes, [Ni(H₂O)₆][ClO₄]₂, CrCl₃·6(H₂O), CeCl₃·7(H₂O), and NiBr₃·3(H₂O) into their aprotic donor congeners, Ni(ClO₄)₂·5.8(CH₃CN), CrCl₃·3.0(THF), CeCl₃·1.5(THF) (or CeCl₃·2LiCl in THF solution), and NiBr₂·1.0(DME), respectively. Additionally, the apparatus proved effective in imine formation reactions where water is produced as a byproduct under equilibrium conditions.</p>","PeriodicalId":56,"journal":{"name":"Organometallics","volume":"44 5","pages":"646–653 646–653"},"PeriodicalIF":2.5,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576652","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}