Beilstein Journal of Organic Chemistry最新文献

{"title":"Synthesis and conformational analysis of pyran inter-halide analogues of ᴅ-talose.","authors":"Olivier Lessard, Mathilde Grosset-Magagne, Paul A Johnson, Denis Giguère","doi":"10.3762/bjoc.20.208","DOIUrl":"10.3762/bjoc.20.208","url":null,"abstract":"<p><p>In this work, we describe the synthesis of halogenated pyran analogues of ᴅ-talose using a halo-divergent strategy from known 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-ᴅ-mannopyranose. In solution and in the solid-state, all analogues adopt standard ⁴ <i>C</i> ₁-like conformations despite 1,3-diaxial repulsion between the F2 and the C4 halogen. Moreover, the solid-state conformational analysis of halogenated pyrans reveals deviation in the intra-annular torsion angles arising from repulsion between the axial fluorine at C2 and the axial halogen at C4, which increases with the size of the halogen at C4 (F < Cl < Br < I). Crystal packing arrangements of pyran inter-halides show hydrogen bond acceptor and nonbonding interactions for the halogen at C4. Finally, density functional theory (DFT) calculations corroborate the preference of talose analogues to adopt a ⁴ <i>C</i> ₁-like conformation and a natural bonding orbital (NBO) analysis demonstrates the effects of hyperconjugation from C-F antibonding orbitals.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2442-2454"},"PeriodicalIF":2.2,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443651/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenylseleno trifluoromethoxylation of alkenes.","authors":"Clément Delobel, Armen Panossian, Gilles Hanquet, Frédéric R Leroux, Fabien Toulgoat, Thierry Billard","doi":"10.3762/bjoc.20.207","DOIUrl":"10.3762/bjoc.20.207","url":null,"abstract":"<p><p>Trifluoromethoxylated molecules and selenylated compounds find a wide range of interesting applications, but separately. In order to combine the potential of these two motifs and to propose a new class of compounds, we have developed an electrophilic phenylseleno trifluoromethoxylation of alkenes, which leads to β-selenylated trifluoromethoxylated compounds or, upon subsequent reduction, to the trifluoromethoxylated ones.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2434-2441"},"PeriodicalIF":2.2,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443662/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Facile preparation of fluorine-containing 2,3-epoxypropanoates and their epoxy ring-opening reactions with various nucleophiles.","authors":"Yutaro Miyashita, Sae Someya, Tomoko Kawasaki-Takasuka, Tomohiro Agou, Takashi Yamazaki","doi":"10.3762/bjoc.20.206","DOIUrl":"10.3762/bjoc.20.206","url":null,"abstract":"<p><p>We describe herein a facile method to access 2,3-epoxyesters with fluorine-containing substituents at their 3-position starting from the corresponding enoates by utilization of the low-costed and easy-to-handle reagent, NaOCl·5H₂O. Because very little has been disclosed about the reactivity of such 2,3-epoxyesters, their epoxy ring opening by a variety of nucleophiles was carried out and we succeeded in clarifying these chemo- as well as regioselective processes proceeding via the S_N2 mechanism to mainly afford 2-substituted 3-hydroxyesters usually in a highly <i>anti</i> selective manner.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2421-2433"},"PeriodicalIF":2.2,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443650/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Homogeneous continuous flow nitration of <i>O</i>-methylisouronium sulfate and its optimization by kinetic modeling.","authors":"Jiapeng Guo, Weike Su, An Su","doi":"10.3762/bjoc.20.205","DOIUrl":"10.3762/bjoc.20.205","url":null,"abstract":"<p><p>Nitration of <i>O</i>-methylisouronium sulfate under mixed acid conditions gives <i>O</i>-methyl-<i>N</i>-nitroisourea, a key intermediate of neonicotinoid insecticides with high application value. The reaction is a fast and highly exothermic process with a high mass transfer resistance, making its control difficult and risky. In this paper, a homogeneous continuous flow microreactor system was developed for the nitration of <i>O</i>-methylisouronium sulfate under high concentrations of mixed acids, with a homemade static mixer eliminating the mass transfer resistance. In addition, the kinetic modeling of this reaction was performed based on the theory of NO₂ ⁺ attack, with the activation energy and pre-exponential factor determined. Finally, based on the response surface generated by the kinetic model, the reaction was optimized with a conversion of 87.4% under a sulfuric acid mass fraction of 94%, initial reactant concentration of 0.5 mol/L, reaction temperature of 40 °C, molar ratio of reactants at 4.4:1, and a residence time of 12.36 minutes.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2408-2420"},"PeriodicalIF":2.2,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11445654/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142368181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the halogen bonding strength of a iodoloisoxazolium(III) salt.","authors":"Dominik L Reinhard, Anna Schmidt, Marc Sons, Julian Wolf, Elric Engelage, Stefan M Huber","doi":"10.3762/bjoc.20.204","DOIUrl":"10.3762/bjoc.20.204","url":null,"abstract":"<p><p>Diaryliodonium(III) salts have been established as powerful halogen-bond donors in recent years. Herein, a new structural motif for this compound class was developed: iodoloisoxazolium salts, bearing a cyclic five-membered iodolium core fused with an isoxazole ring. A derivative of this class was synthesized and investigated in the solid state by X-ray crystallography. Finally, the potential as halogen-bonding activator was benchmarked in solution in the gold-catalyzed cyclization of a propargyl amide.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2401-2407"},"PeriodicalIF":2.2,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443664/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient one-step synthesis of diarylacetic acids by electrochemical direct carboxylation of diarylmethanol compounds in DMSO.","authors":"Hisanori Senboku, Mizuki Hayama","doi":"10.3762/bjoc.20.203","DOIUrl":"https://doi.org/10.3762/bjoc.20.203","url":null,"abstract":"<p><p>An efficient one-step synthesis of diarylacetic acids was successfully performed by electrochemical direct carboxylation of diarylmethanol compounds in DMSO. Constant-current electrolysis of diarylmethanol species in DMSO using a one-compartment cell equipped with a Pt cathode and a Mg anode in the presence of carbon dioxide induced reductive C(sp³)-O bond cleavage at the benzylic position in diarylmethanol compounds and subsequent fixation of carbon dioxide to produce diarylacetic acids in good yield. This protocol provides a novel and simple approach to diarylacetic acids from diarylmethanol species and carbon dioxide without transformation of the hydroxy group into appropriate leaving groups, such as halides and esters including carbonates.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"20 ","pages":"2392-2400"},"PeriodicalIF":2.2,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11420549/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142340300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, electrochemical properties, and antioxidant activity of sterically hindered catechols with 1,3,4-oxadiazole, 1,2,4-triazole, thiazole or pyridine fragments","authors":"Daria A. Burmistrova, Andrey Galustyan, Nadezhda P. Pomortseva, Kristina D. Pashaeva, Maxim V. Arsenyev, Oleg P. Demidov, Mikhail A. Kiskin, Andrey I. Poddel’sky, Nadezhda T. Berberova, Ivan V. Smolyaninov","doi":"10.3762/bjoc.20.202","DOIUrl":"https://doi.org/10.3762/bjoc.20.202","url":null,"abstract":"<p><font size='+1'><b>Abstract</b></font></p>\u0000<p>A series of new RS&#8722;, RS&#8722;CH₂&#8722; and R₂N&#8722;CH₂-functionalized &#1089;atechols with heterocyclic fragments such as 1,3,4-oxadiazole, 1,2,4-triazole, thiazole, or pyridine were synthesized by the reaction of 3,5-di-<i>tert</i>-butyl-<i>o</i>-benzoquinone or 3,5-di-<i>tert</i>-butyl-6-methoxymethylcatechol with different heterocyclic thiols. The S-functionalized catechols were prepared by the Michael reaction from 3,5-di-<i>tert</i>-butyl-<i>o</i>-benzoquinone and the corresponding thiols. The starting reagents such as substituted 1,3,4-oxadiazole-2-thiols and 4<i>H</i>-triazole-3-thiols are characterized by thiol&#8211;thione tautomerism, therefore their reactions with 3,5-di-<i>tert</i>-butyl-6-methoxymethylcatechol can proceed at the sulfur or nitrogen atom. In the case of mercapto-derivatives of thiazole or pyridine, this process leads to the formation of the corresponding thioethers with a methylene linker. At the same time, thiolated 1,3,4-oxadiazole or 1,2,4-triazole undergo alkylation at the nitrogen atom in the reaction with 3,5-di-<i>tert</i>-butyl-6-methoxymethylcatechol to form the corresponding thiones. The yield of reaction products ranges from 42 to 80%. The crystal structures of catechols with 3-nitropyridine or 1,3,4-oxadiazole-2(3<i>H</i>)-thione moieties were established by single-crystal X-ray analysis. The possibility of forming intra- and intermolecular hydrogen bonds has been established for these compounds. The electrochemical behavior of the studied compounds is influenced by several factors: the nature of the heterocycle and its substituents, the presence of a sulfur atom in the catechol ring, or a thione group in the heterocyclic core. The radical scavenging activity and antioxidant properties were determined using the reaction with synthetic radicals, the cupric reducing antioxidant capacity assay, the inhibition process of superoxide radical anion formation by xanthine oxidase, and the process of lipid peroxidation of rat liver (<i>Wistar</i>) homogenates in vitro.</p>\u0000<p align='center'><img src='https://www.beilstein-journals.org/bjoc/content/figures/1860-5397-20-202-graphical-abstract.png?max-width=550' border='0'/></p>\u0000<p><i>Beilstein J. Org. Chem.</i> <b>2024,</b> <i>20,</i> 2378&#8211;2391.&#160;doi:10.3762/bjoc.20.202</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"4 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system","authors":"Yuri A. Sidunets, Valeriya G. Melekhina, Leonid L. Fershtat","doi":"10.3762/bjoc.20.200","DOIUrl":"https://doi.org/10.3762/bjoc.20.200","url":null,"abstract":"<p><font size='+1'><b>Abstract</b></font></p>\u0000<p>A straightforward protocol for the synthesis of a previously unknown [1,2,5]oxadiazolo[3,4-<i>d</i>][1,2,3]triazin-7(6<i>H</i>)-one heterocyclic system was developed. The described approach is based on tandem diazotization/azo coupling reactions of (1,2,5-oxadiazolyl)carboxamide derivatives bearing both aromatic and aliphatic substituents. The NO-donor ability of the synthesized furoxano[3,4-<i>d</i>][1,2,3]triazin-7(6<i>H</i>)-ones was additionally evaluated. The elaborated method provides access to novel nitrogen heterocyclic compounds with potential applications as drug candidates or thermostable components of functional organic materials.</p>\u0000<p align='center'><img src='https://www.beilstein-journals.org/bjoc/content/figures/1860-5397-20-200-graphical-abstract.png?max-width=550' border='0'/></p>\u0000<p><i>Beilstein J. Org. Chem.</i> <b>2024,</b> <i>20,</i> 2342&#8211;2348.&#160;doi:10.3762/bjoc.20.200</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"64 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetric organocatalytic synthesis of chiral homoallylic amines","authors":"Nikolay S. Kondratyev, Andrei V. Malkov","doi":"10.3762/bjoc.20.201","DOIUrl":"https://doi.org/10.3762/bjoc.20.201","url":null,"abstract":"<p><font size='+1'><b>Abstract</b></font></p>\u0000<p>In recent decades, the chiral allylation of imines emerged as a key methodology in the synthesis of alkaloids and natural products with 4-, 5- and 6-membered cyclic amine motifs. Initially reliant on stoichiometric reagents, synthetic chemists predominantly used <i>N</i>-substituted chiral imines, organometallic chiral reagents and achiral reagents with an equimolar chiral controller. However, recent years have witnessed the rise of asymmetric transition-metal catalysts and, importantly, organocatalytic allylation, reshaping the landscape of modern synthetic chemistry. This review explores the latest developments in the asymmetric allylation of imines, encompassing cutting-edge advances in hydrogen-bond catalysis and non-classical approaches. Furthermore, practical examples showcasing the application of these innovative methodologies in total synthesis are presented.</p>\u0000<p align='center'><img src='https://www.beilstein-journals.org/bjoc/content/figures/1860-5397-20-201-graphical-abstract.png?max-width=550' border='0'/></p>\u0000<p><i>Beilstein J. Org. Chem.</i> <b>2024,</b> <i>20,</i> 2349&#8211;2377.&#160;doi:10.3762/bjoc.20.201</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"38 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142247459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stereoselective mechanochemical synthesis of thiomalonate Michael adducts via iminium catalysis by chiral primary amines","authors":"Michał Błauciak, Dominika Andrzejczyk, Błażej Dziuk, Rafał Kowalczyk","doi":"10.3762/bjoc.20.198","DOIUrl":"https://doi.org/10.3762/bjoc.20.198","url":null,"abstract":"<p><font size='+1'><b>Abstract</b></font></p>\u0000<p>The study presents a novel approach utilizing iminium salt activation and mild enolization of thioesters, offering an efficient and rapid synthesis of Michael adducts with promising stereoselectivity and marking a significant advancement in mechanocatalysis. The stereoselective addition of bisthiomalonates <b>1</b>&#8211;<b>4</b> to cyclic enones and 4-chlorobenzylideneacetone proceeds stereoselectively under iminium activation conditions secured by chiral primary amines, in contrast to oxo-esters as observed in dibenzyl malonate addition. Mild enolization of thioesters allows for the generation of Michael adducts with good yields and stereoselectivities. Reactions in a ball mill afford product formation with similar efficacy to solution-phase reactions but with slightly reduced enantioselectivity, yet they yield products in just one hour compared to 24 or even 168 hours in solution-based reactions. It is noteworthy that this represents one of the early reports on the application of iminium catalysis using first-generation chiral amines under mechanochemical conditions, along with the utilization of easily enolizable thioesters as nucleophiles in this transformation.</p>\u0000<p align='center'><img src='https://www.beilstein-journals.org/bjoc/content/figures/1860-5397-20-198-graphical-abstract.png?max-width=550' border='0'/></p>\u0000<p><i>Beilstein J. Org. Chem.</i> <b>2024,</b> <i>20,</i> 2313&#8211;2322.&#160;doi:10.3762/bjoc.20.198</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"11 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142184996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}