We report a straightforward, catalyst-free method for the cathodic benzylic C–H hydroxyalkylation/arylation of N-(alkyloxy)phthalimides with ketones or cyanopyridines. The reaction is driven by an electrochemically induced 1,2-hydrogen atom transfer involving alkoxy radicals generated by O–N bond cleavage. This protocol provides an efficient approach for the synthesis of a wide range of valuable unsymmetrical 1,2-diols and diarylmethanols.
{"title":"Electrochemical 1,2-hydrogen atom transfer functionalizations of N-(benzyloxy)phthalimides†","authors":"Xin Fu, Tingting Ran and Jie Liu","doi":"10.1039/D4QO01607F","DOIUrl":"10.1039/D4QO01607F","url":null,"abstract":"<p >We report a straightforward, catalyst-free method for the cathodic benzylic C–H hydroxyalkylation/arylation of <em>N</em>-(alkyloxy)phthalimides with ketones or cyanopyridines. The reaction is driven by an electrochemically induced 1,2-hydrogen atom transfer involving alkoxy radicals generated by O–N bond cleavage. This protocol provides an efficient approach for the synthesis of a wide range of valuable unsymmetrical 1,2-diols and diarylmethanols.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6760-6767"},"PeriodicalIF":4.6,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhou Luo, Tianxiang Fan, Jingyan Luo, Yuanyuan Liu and Junliang Zhang
A diverse array of bidentate P-containing ligands has been developed for Ir-catalyzed asymmetric hydrogenation, but chiral monodentate phosphine ligands have remained comparatively underexplored. We herein report a novel iridium catalyst with XuPhos as a chiral monodentate phosphine ligand for the direct asymmetric reductive amination of ketones with secondary amines. This catalytic system tolerates a wide range of substrates, providing a series of chiral tertiary amines efficiently with high enantioselectivities. The high catalytic activity is attributed to the presence of the aliphatic cyclohexyl group on the P-atom and the relative configuration of the ligand, which is crucial for XuPhos to act as a monodentate P-ligand for iridium.
目前已开发出多种双齿含 P 配体用于铱催化的不对称氢化反应,但对手性单齿膦配体的研究相对不足。我们在此报告了一种新型铱催化剂,该催化剂以 XuPhos 作为手性单齿膦配体,用于酮与仲胺的直接不对称还原胺化反应。该催化体系可耐受多种底物,能高效地提供一系列手性叔胺,并具有很高的对映选择性。高催化活性归功于 P 原子上脂肪族环己基的存在和配体的相对构型,这对于 XuPhos 作为铱的单位 P 配体至关重要。
{"title":"Ir/XuPhos-catalyzed direct asymmetric reductive amination of ketones with secondary amines†","authors":"Zhou Luo, Tianxiang Fan, Jingyan Luo, Yuanyuan Liu and Junliang Zhang","doi":"10.1039/D4QO01495B","DOIUrl":"10.1039/D4QO01495B","url":null,"abstract":"<p >A diverse array of bidentate P-containing ligands has been developed for Ir-catalyzed asymmetric hydrogenation, but chiral monodentate phosphine ligands have remained comparatively underexplored. We herein report a novel iridium catalyst with <strong>XuPhos</strong> as a chiral monodentate phosphine ligand for the direct asymmetric reductive amination of ketones with secondary amines. This catalytic system tolerates a wide range of substrates, providing a series of chiral tertiary amines efficiently with high enantioselectivities. The high catalytic activity is attributed to the presence of the aliphatic cyclohexyl group on the P-atom and the relative configuration of the ligand, which is crucial for <strong>XuPhos</strong> to act as a monodentate P-ligand for iridium.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6735-6741"},"PeriodicalIF":4.6,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhe Jin, Tingwei Yu, Hui Wang, Penghao Jia and You Huang
Organosulfur compounds, especially sulfur ylides and sulfonium salts, offer extraordinary potential in organic chemistry due to their distinctive structural properties and reactivities. In the past five years, tremendous progress has been made in sulfur ylide and sulfonium salt chemistry with the advent of photoredox catalysis. Increasing unprecedented reactivities and reactions of organosulfur compounds have been unearthed, which are distinguished from their conventional ionic reactivity. This review highlights the recent advances in alkylation procedures with sulfur ylides, sulfoxonium ylides, sulfonium salts and thianthrenium salts driven by photocatalysis—with emphases on reactions, mechanisms, and applications—aiming to provide guidance for the potential of sulfur-containing species in a wide range of reactions and to inspire further progress in organosulfur chemistry.
{"title":"Shining light on sulfonium salts and sulfur ylides: recent advances in alkylation under photoredox catalysis","authors":"Zhe Jin, Tingwei Yu, Hui Wang, Penghao Jia and You Huang","doi":"10.1039/D4QO01644K","DOIUrl":"10.1039/D4QO01644K","url":null,"abstract":"<p >Organosulfur compounds, especially sulfur ylides and sulfonium salts, offer extraordinary potential in organic chemistry due to their distinctive structural properties and reactivities. In the past five years, tremendous progress has been made in sulfur ylide and sulfonium salt chemistry with the advent of photoredox catalysis. Increasing unprecedented reactivities and reactions of organosulfur compounds have been unearthed, which are distinguished from their conventional ionic reactivity. This review highlights the recent advances in alkylation procedures with sulfur ylides, sulfoxonium ylides, sulfonium salts and thianthrenium salts driven by photocatalysis—with emphases on reactions, mechanisms, and applications—aiming to provide guidance for the potential of sulfur-containing species in a wide range of reactions and to inspire further progress in organosulfur chemistry.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 22","pages":" 6573-6588"},"PeriodicalIF":4.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
gem-Difluorocyclopropanes (F2CPs), a unique class of cyclopropanes, have attracted particular interest of chemists due to their intrinsic reactivity. In this context, gem-F2CPs have been extensively studied as fluoroallylic synthons in transition metal-catalysed ring-opening/cross-coupling reactions for the preparation of linear/branched monofluoroalkenes via single C–F bond cleavage. In addition, various transformations of gem-F2CPs via double or no C–F bond cleavage have also been rapidly developed. This mini-review summarizes these advances and briefly discusses the design, selectivity, and reaction mechanism, with a particular focus on the last two years.
{"title":"Recent developments in the ring-opening transformations of gem-difluorocyclopropanes","authors":"Leiyang Lv, Junqi Su and Zhiping Li","doi":"10.1039/D4QO01583E","DOIUrl":"10.1039/D4QO01583E","url":null,"abstract":"<p > <em>gem</em>-Difluorocyclopropanes (F<small><sub>2</sub></small>CPs), a unique class of cyclopropanes, have attracted particular interest of chemists due to their intrinsic reactivity. In this context, <em>gem</em>-F<small><sub>2</sub></small>CPs have been extensively studied as fluoroallylic synthons in transition metal-catalysed ring-opening/cross-coupling reactions for the preparation of linear/branched monofluoroalkenes <em>via</em> single C–F bond cleavage. In addition, various transformations of <em>gem</em>-F<small><sub>2</sub></small>CPs <em>via</em> double or no C–F bond cleavage have also been rapidly developed. This mini-review summarizes these advances and briefly discusses the design, selectivity, and reaction mechanism, with a particular focus on the last two years.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 22","pages":" 6518-6533"},"PeriodicalIF":4.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142368862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fa-Dong Wang, Kai-Kai Niu, Shengsheng Yu, Hui Liu and Ling-Bao Xing
Enhancing the photocatalytic efficiency of organic photocatalysts and increasing the generation capacity of reactive oxygen species (ROS) have consistently been substantial obstacles. In this study, we designed and synthesized a supramolecular dimer based on anthraquinone (Amvp-CB[8]) between the methylated vinylpyridinium substituted anthraquinone derivative (Amvp) and cucurbit[8]uril (CB[8]) through host–guest interactions in the aqueous solution. Compared to the monomer Amvp, the supramolecular dimer Amvp-CB[8] exhibited significantly enhanced fluorescence and demonstrated remarkable capabilities in generating singlet oxygen (1O2) and superoxide anion radicals (O2˙−) in water. Importantly, Amvp-CB[8] displayed superior photocatalytic activity under visible light, facilitating efficient photoredox thiol–ene cross-coupling reactions between phenthiol and styrene, which selectively enabled rapid synthesis of sulfides within 0.5 h and sulfoxides within 12 h, showcasing high efficiency, low catalyst loading, and excellent functional group tolerance. This study introduces a novel supramolecular dimer strategy that enhances the design of efficient photocatalysts for organic conversions in photocatalysis.
{"title":"A supramolecular dimer strategy for enhancing the selective generation of sulfides and sulfoxides by visible-light induced photoredox thiol–ene cross-coupling reactions of anthraquinone†","authors":"Fa-Dong Wang, Kai-Kai Niu, Shengsheng Yu, Hui Liu and Ling-Bao Xing","doi":"10.1039/D4QO01454E","DOIUrl":"10.1039/D4QO01454E","url":null,"abstract":"<p >Enhancing the photocatalytic efficiency of organic photocatalysts and increasing the generation capacity of reactive oxygen species (ROS) have consistently been substantial obstacles. In this study, we designed and synthesized a supramolecular dimer based on anthraquinone (Amvp-CB[8]) between the methylated vinylpyridinium substituted anthraquinone derivative (Amvp) and cucurbit[8]uril (CB[8]) through host–guest interactions in the aqueous solution. Compared to the monomer Amvp, the supramolecular dimer Amvp-CB[8] exhibited significantly enhanced fluorescence and demonstrated remarkable capabilities in generating singlet oxygen (<small><sup>1</sup></small>O<small><sub>2</sub></small>) and superoxide anion radicals (O<small><sub>2</sub></small>˙<small><sup>−</sup></small>) in water. Importantly, Amvp-CB[8] displayed superior photocatalytic activity under visible light, facilitating efficient photoredox thiol–ene cross-coupling reactions between phenthiol and styrene, which selectively enabled rapid synthesis of sulfides within 0.5 h and sulfoxides within 12 h, showcasing high efficiency, low catalyst loading, and excellent functional group tolerance. This study introduces a novel supramolecular dimer strategy that enhances the design of efficient photocatalysts for organic conversions in photocatalysis.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6684-6693"},"PeriodicalIF":4.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142368863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weiping Zhou, Ya-Qing Huang, Vincent Gandon and Arnaud Voituriez
Starting with vinyl sulfoxides and propargyl silane, the Au(I)-catalyzed asymmetric [3,3]-sigmatropic rearrangement of sulfonium intermediates furnished, after a protodemetallation step and hydrolysis of a thionium ion, the corresponding 4-oxo-2-aryl-2-alkyl-pentanal derivatives. From the fine analysis of crude mixtures representative of this transformation, formal α-arylated products of acetone (1-arylpropan-2-one derivatives) and aryl sulfanes were also isolated and characterized, depending on the substrates and reaction conditions used. Therefore, a tentative mechanistic explanation of the formation of these unexpected products was highlighted and DFT calculations have also streamlined the reactivity of these cationic gold(I)-catalyzed transformations.
{"title":"Mechanistic insights into the gold(i)-catalyzed [3,3]-sigmatropic rearrangement of sulfoniums for the formation of chiral 1,4-dicarbonyls or formal α-arylation of carbonyl compounds†","authors":"Weiping Zhou, Ya-Qing Huang, Vincent Gandon and Arnaud Voituriez","doi":"10.1039/D4QO01061B","DOIUrl":"10.1039/D4QO01061B","url":null,"abstract":"<p >Starting with vinyl sulfoxides and propargyl silane, the Au(<small>I</small>)-catalyzed asymmetric [3,3]-sigmatropic rearrangement of sulfonium intermediates furnished, after a protodemetallation step and hydrolysis of a thionium ion, the corresponding 4-oxo-2-aryl-2-alkyl-pentanal derivatives. From the fine analysis of crude mixtures representative of this transformation, formal α-arylated products of acetone (1-arylpropan-2-one derivatives) and aryl sulfanes were also isolated and characterized, depending on the substrates and reaction conditions used. Therefore, a tentative mechanistic explanation of the formation of these unexpected products was highlighted and DFT calculations have also streamlined the reactivity of these cationic gold(<small>I</small>)-catalyzed transformations.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6804-6812"},"PeriodicalIF":4.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142368861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Parag Mistry, Subhankar Das, Rik Patra and Indranil Chatterjee
The synthesis of amides and their derivatives has gained significant attention from the scientific community in recent decades due to the presence of amide moieties in many bioactive organic molecules. Pursuing sustainable chemistry using cost-effective starting materials under mild reaction conditions is intriguing and challenging. In this context, we present a method for the direct synthesis of amides from α-keto acids and α-iminoesters. This approach employs an Ir-based photocatalyst to enable redox-neutral C–N bond formation at room temperature through N-center umpolung chemistry. This straightforward protocol is compatible with a broad range of functional groups, allowing for the efficient production of amides from aromatic keto acids and imines as coupling partners in an atom-economical manner.
近几十年来,由于许多生物活性有机分子中存在酰胺分子,酰胺及其衍生物的合成在科学界获得了极大关注。在温和的反应条件下,利用具有成本效益的起始材料追求可持续化学是一件既有趣又具有挑战性的事情。在此背景下,我们提出了一种从 α-酮酸和 α-亚胺酯直接合成酰胺的方法。这种方法采用了一种基于 Ir 的光催化剂,通过 N 中心的umpolung 化学反应,在室温下形成氧化还原中性的 C-N 键。这种简单易行的方法与多种官能团兼容,能以原子经济的方式从芳香酮酸和亚胺作为偶联剂高效生产酰胺。
{"title":"Exploring N-centered umpolung reactivity in photoredox-catalyzed amidation with an α-iminoester†","authors":"Parag Mistry, Subhankar Das, Rik Patra and Indranil Chatterjee","doi":"10.1039/D4QO01515K","DOIUrl":"10.1039/D4QO01515K","url":null,"abstract":"<p >The synthesis of amides and their derivatives has gained significant attention from the scientific community in recent decades due to the presence of amide moieties in many bioactive organic molecules. Pursuing sustainable chemistry using cost-effective starting materials under mild reaction conditions is intriguing and challenging. In this context, we present a method for the direct synthesis of amides from α-keto acids and α-iminoesters. This approach employs an Ir-based photocatalyst to enable redox-neutral C–N bond formation at room temperature through N-center umpolung chemistry. This straightforward protocol is compatible with a broad range of functional groups, allowing for the efficient production of amides from aromatic keto acids and imines as coupling partners in an atom-economical manner.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6778-6783"},"PeriodicalIF":4.6,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yohei Haketa, Maho Kawami, Wataru Ota, Tohru Sato and Hiromitsu Maeda
Naphthylisoquinoline-appended dipyrrolyldiketone PtII complexes as helical π-electronic systems were synthesized. The PtII complexes, showing chiroptical properties in solution, exhibited anion-binding behaviour, resulting in the formation of anion complexes as pseudo π-electronic anions. In combination with the π-electronic cation, the receptor–anion complexes formed charge-by-charge ion-pairing assemblies, with the narcissistic self-sorting columnar structures comprising either of the enantiomers, in the crystal state.
{"title":"Ion-pairing assemblies of anion-responsive helical PtII complexes†","authors":"Yohei Haketa, Maho Kawami, Wataru Ota, Tohru Sato and Hiromitsu Maeda","doi":"10.1039/D4QO01697A","DOIUrl":"10.1039/D4QO01697A","url":null,"abstract":"<p >Naphthylisoquinoline-appended dipyrrolyldiketone Pt<small><sup>II</sup></small> complexes as helical π-electronic systems were synthesized. The Pt<small><sup>II</sup></small> complexes, showing chiroptical properties in solution, exhibited anion-binding behaviour, resulting in the formation of anion complexes as pseudo π-electronic anions. In combination with the π-electronic cation, the receptor–anion complexes formed charge-by-charge ion-pairing assemblies, with the narcissistic self-sorting columnar structures comprising either of the enantiomers, in the crystal state.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6651-6659"},"PeriodicalIF":4.6,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jaqueline S. A. Badaro, Antoni Wrzosek, Olaf Morawski, Adam Szewczyk, Irena Deperasińska and Daniel T. Gryko
It is now possible to prepare 2-oxo-2H-pyrano[2,3-b]indolizine-3-carboxylates with an ordered arrangement of various substituents directly from pyridinium salts and diethyl 2-(ethoxymethylene)malonate, allowing for refined control of their photophysical properties. Facile entry into some previously unknown derivatives is disclosed to demonstrate the potential of this method. The use of substituted picolinium salts, as well as further functionalization of the pyrrole ring, permitted easy introduction of new moieties upon the dye, which enabled fine-tuning of the photophysical properties. The obtained dyes possess absorption and emission spectrum in the blue–green region and fluorescence quantum yields reaching 92%. The parent 2-oxo-pyrano[2,3-b]indolizine-3-carboxylate turned out to be an electron-deficient system with a low-lying LUMO, an electronic transition energy of 2.7 eV and possessing a large oscillator strength. Almost complete overlap of the HOMO and LUMO in the 2-oxo-pyrano[2,3-b]indolizine core is responsible for the large fluorescence quantum yields for almost all prepared derivatives. The reason for maintaining the large emission intensity in polar solvents is that the increase in the dipole moment is accompanied with a significant change in its orientation in space. Fluorescence imaging studies have proven that 2-oxo-pyrano[2,3-b]indolizines penetrate the membrane of living cells. A positively charged analog was synthesized and used to stain intracellular organelles in the H9c2 cell line. This compound did not penetrate the cell membrane, however after permeabilization, it specifically stained the nucleus.
{"title":"Strongly fluorescent indolizine-based coumarin analogs†","authors":"Jaqueline S. A. Badaro, Antoni Wrzosek, Olaf Morawski, Adam Szewczyk, Irena Deperasińska and Daniel T. Gryko","doi":"10.1039/D4QO01216J","DOIUrl":"10.1039/D4QO01216J","url":null,"abstract":"<p >It is now possible to prepare 2-oxo-2<em>H</em>-pyrano[2,3-<em>b</em>]indolizine-3-carboxylates with an ordered arrangement of various substituents directly from pyridinium salts and diethyl 2-(ethoxymethylene)malonate, allowing for refined control of their photophysical properties. Facile entry into some previously unknown derivatives is disclosed to demonstrate the potential of this method. The use of substituted picolinium salts, as well as further functionalization of the pyrrole ring, permitted easy introduction of new moieties upon the dye, which enabled fine-tuning of the photophysical properties. The obtained dyes possess absorption and emission spectrum in the blue–green region and fluorescence quantum yields reaching 92%. The parent 2-oxo-pyrano[2,3-<em>b</em>]indolizine-3-carboxylate turned out to be an electron-deficient system with a low-lying LUMO, an electronic transition energy of 2.7 eV and possessing a large oscillator strength. Almost complete overlap of the HOMO and LUMO in the 2-oxo-pyrano[2,3-<em>b</em>]indolizine core is responsible for the large fluorescence quantum yields for almost all prepared derivatives. The reason for maintaining the large emission intensity in polar solvents is that the increase in the dipole moment is accompanied with a significant change in its orientation in space. Fluorescence imaging studies have proven that 2-oxo-pyrano[2,3-<em>b</em>]indolizines penetrate the membrane of living cells. A positively charged analog was synthesized and used to stain intracellular organelles in the H9c2 cell line. This compound did not penetrate the cell membrane, however after permeabilization, it specifically stained the nucleus.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6627-6641"},"PeriodicalIF":4.6,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/qo/d4qo01216j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142362958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Junyi Zhou, Xiang Wang, Wenjun Tang and Liqin Jiang
The hypervalent iodine(III) mediated oxo/aza/carbon/difluorination of alkenes has made significant progress, although the corresponding fluorination of alkynes cannot be accomplished. However, hypervalent iodine(III) mediated thiofluorination of both alkenes and alkynes has never been achieved before. Herein, three-component alkenyl thiocarbamoyl fluorides, water, and Et3N·3HF or two-component alkenyl thioureas and Et3N·3HF proceeded through cascade hydrolysis/thiofluorination or thiofluorination of terminal/internal unactivated/activated alkenes upon phenyliodine(III)bis(pivalate) in toluene at room temperature, providing access to diversified monofluorinated 1,3-thiazolidin-2-ones, 1,3-thiazinan-2-ones, 2-imino-thiazolidines and 1,3-thiazinan-2-imines with a broad substrate scope, excellent functional group tolerance and excellent regioselectivity. Configurations of some products were found to be opposite to those expected from the traditional mechanism of olefin activation by hypervalent iodines(III). Based on mechanistic studies and product configurations, another mechanism involving a cyclic sulfonium ion intermediate was proposed. This inspired us to further discover that phenyliodine(III)bis(pivalate) with dioxane as solvent enabled thiofuorination of alkynes from alkynyl thioureas and Et3N·3HF, furnishing 2-imino-thiazolidines bearing an exocyclicfluoromethylene as tetrasubstituted fluorinated alkenes with remarkable regio-, chemo- and stereoselectivity (absolute E-isomer). These transformations represent the unprecedented thiofluorination of alkenes/alkynes in one operation directly from nucleophilic sulfur reagents and nucleophilic fluorine reagents.
{"title":"Hypervalent iodide(iii)-mediated thiofluorination of alkenes and alkynes from thioureas/thiocarbamoyl fluorides with water and a nucleophilic fluoride source†","authors":"Junyi Zhou, Xiang Wang, Wenjun Tang and Liqin Jiang","doi":"10.1039/D4QO01569J","DOIUrl":"10.1039/D4QO01569J","url":null,"abstract":"<p >The hypervalent iodine(<small>III</small>) mediated oxo/aza/carbon/difluorination of alkenes has made significant progress, although the corresponding fluorination of alkynes cannot be accomplished. However, hypervalent iodine(<small>III</small>) mediated thiofluorination of both alkenes and alkynes has never been achieved before. Herein, three-component alkenyl thiocarbamoyl fluorides, water, and Et<small><sub>3</sub></small>N·3HF or two-component alkenyl thioureas and Et<small><sub>3</sub></small>N·3HF proceeded through cascade hydrolysis/thiofluorination or thiofluorination of terminal/internal unactivated/activated alkenes upon phenyliodine(<small>III</small>)bis(pivalate) in toluene at room temperature, providing access to diversified monofluorinated 1,3-thiazolidin-2-ones, 1,3-thiazinan-2-ones, 2-imino-thiazolidines and 1,3-thiazinan-2-imines with a broad substrate scope, excellent functional group tolerance and excellent regioselectivity. Configurations of some products were found to be opposite to those expected from the traditional mechanism of olefin activation by hypervalent iodines(<small>III</small>). Based on mechanistic studies and product configurations, another mechanism involving a cyclic sulfonium ion intermediate was proposed. This inspired us to further discover that phenyliodine(<small>III</small>)bis(pivalate) with dioxane as solvent enabled thiofuorination of alkynes from alkynyl thioureas and Et<small><sub>3</sub></small>N·3HF, furnishing 2-imino-thiazolidines bearing an exocyclicfluoromethylene as tetrasubstituted fluorinated alkenes with remarkable regio-, chemo- and stereoselectivity (absolute <em>E</em>-isomer). These transformations represent the unprecedented thiofluorination of alkenes/alkynes in one operation directly from nucleophilic sulfur reagents and nucleophilic fluorine reagents.</p>","PeriodicalId":97,"journal":{"name":"Organic Chemistry Frontiers","volume":" 23","pages":" 6748-6759"},"PeriodicalIF":4.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}