Beilstein Journal of Organic Chemistry最新文献

{"title":"Calcium waste as a catalyst in the transesterification for demanding esters: scalability perspective.","authors":"Anton N Potorochenko, Konstantin S Rodygin","doi":"10.3762/bjoc.21.114","DOIUrl":"10.3762/bjoc.21.114","url":null,"abstract":"<p><p>Esters are valuable compounds in fine organic synthesis and industry. The significant growth in the demand for esters requires the development of scalable production methods. Heterogeneous CaO-based catalysts for the production of esters by transesterification are promising catalytic systems for the production of these desired compounds. In this work, the application of calcium carbide slag, a byproduct of acetylene production, was investigated. The catalyst was obtained by calcination of calcium carbide slag at 600 °C (CS₆₀₀) and characterized by XRD and FTIR analysis. The transesterification reactions were carried out with primary alcohols, producing fatty acid alkyl esters in 51-99% yields, depending on the alcohols' nature and catalyst amount (1-10 wt %). The CS₆₀₀ catalyst demonstrated efficiency in the transesterification of low-molecular-weight esters, medium-chain triglycerides (C₉-C₁₂), and lactones, resulting in the corresponding methyl esters in 66-99% yields in the presence of low catalyst amounts of 1-5 wt %.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1520-1527"},"PeriodicalIF":2.1,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12320737/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144783375","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":"Azobenzene protonation as a tool for temperature sensing.","authors":"Antti Siiskonen, Sami Vesamäki, Arri Priimagi","doi":"10.3762/bjoc.21.115","DOIUrl":"10.3762/bjoc.21.115","url":null,"abstract":"<p><p>Azobenzenes can be protonated at one of the azo nitrogen atoms, leading to significant changes in their absorption and photochemical properties. While azobenzene protonation has been recently used as a tool in photoswitching studies, the factors influencing protonation itself have received little attention. Here, we report a strong temperature dependence of azobenzene protonation in 1,2-dichloroethane and highlight its potential for temperature sensing applications. Density functional theory calculations were performed to support our findings and to investigate the mechanisms of azobenzene-acid interactions, aiming to guide the design of azobenzene-based temperature sensors in future research.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1528-1534"},"PeriodicalIF":2.1,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12320741/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144783374","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":"Ambident reactivity of enolizable 5-mercapto-1<i>H</i>-tetrazoles in trapping reactions with in situ-generated thiocarbonyl <i>S</i>-methanides derived from sterically crowded cycloaliphatic thioketones.","authors":"Grzegorz Mlostoń, Małgorzata Celeda, Marcin Palusiak, Heinz Heimgartner, Marta Denel-Bobrowska, Agnieszka B Olejniczak","doi":"10.3762/bjoc.21.113","DOIUrl":"10.3762/bjoc.21.113","url":null,"abstract":"<p><p>The in situ-generated thiocarbonyl <i>S</i>-methanides (thiocarbonyl ylides), derived from cycloaliphatic thioketones, are efficiently trapped by enolizable 1-substitued 5-mercapto-1<i>H</i>-tetrazoles and formation of the corresponding N-H or S-H insertion products, i.e., thioaminals or dithioacetals, respectively, was observed. In some instances, both products were formed side by side and could be separated by chromatography. Two novel, sterically overcrowded bis-spiro(cyclopentyl) and bis-spiro(cyclohexyl)-substituted thiocarbonyl <i>S</i>-methanides were thermally generated from the corresponding 1,3,4-thiadiazolines and their reactivity towards 5-mercapto-1<i>H</i>-tetrazoles was compared with well-known analogues derived from adamantanethione and 2,2,4,4-tetramethyl-3-thioxocyclobutanone. Some of the isolated thioaminals were observed to undergo thermal isomerization in CDCl₃ solution yielding the corresponding dithioacetals. Structural analysis of the isolated products of S-H and N-H insertion was carried out based on spectroscopic data (¹H and ¹³C NMR) and the structures of two representatives were established by using the X-ray single crystal diffraction analysis method. Biological activity (cytotoxicity) of some selected products derived from 5-mercapto-1<i>H</i>-tetrazoles was also examined.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1508-1519"},"PeriodicalIF":2.1,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12302482/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144727150","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":"Highly distinguishable isomeric states of a tripodal arylazopyrazole derivative on graphite through electron/hole-induced switching at ambient conditions.","authors":"Himani Malik, Sudha Devi, Debapriya Gupta, Ankit Kumar Gaur, Sugumar Venkataramani, Thiruvancheril G Gopakumar","doi":"10.3762/bjoc.21.112","DOIUrl":"10.3762/bjoc.21.112","url":null,"abstract":"<p><p>Manipulating the energy barrier and extending the half-life of nonequilibrium states in photochromic switches presents viable solutions for applying them in molecular electronics. Typically, the half-life of the <i>Z</i> isomer of azobenzene (AB) is a few days. Arylazopyrazole-based molecular switches are one of the profoundly explored systems in recent times due to their superior bidirectional photoswitching and long half-life (over a thousand days at room temperature) of <i>Z</i> isomers. Herein, we utilize an efficient solid-state photoswitchable fluorinated tripodal <i>N</i>-functionalized arylazo-3,5-dimethylpyrazole derivative (FNAAP) to envisage and access multiple metastable states on the surface. The tripodal molecule forms well-ordered, large crystalline domains on graphite through non-bonding interactions between the molecules. By injecting electron/hole pairs into the self-assembled molecules on a surface using a scanning tunneling microscope (STM) tip, they are switched between 8 states (<i>EEE</i>, <i>EEZ</i>, <i>EZE</i>, <i>ZEE</i>, <i>EZZ</i>, <i>ZEZ</i>, <i>ZZE</i> and <i>ZZZ</i>) in a tunneling junction at ambient conditions. Contrary to the degeneracy-controlled four states in solution phase, all the eight states are remarkably stable on the surface and are well distinguishable by the tunneling current passing through the molecule at the tunneling junction. The change in current upon switching between these states is approximately an order of magnitude. This is particularly notable at positive sample voltage compared to negative sample voltage. The exceptional stability of the states at ambient conditions provides an opportunity to use a single FNAAP molecule as an 8-bit operation unit, with a potential storage capacity of ≈200 Tbits per 1 cm² area using an atomically precise write and read tool like an STM tip.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1496-1507"},"PeriodicalIF":2.1,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12302408/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144727152","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":"Photoredox-catalyzed arylation of isonitriles by diaryliodonium salts towards benzamides.","authors":"Nadezhda M Metalnikova, Nikita S Antonkin, Tuan K Nguyen, Natalia S Soldatova, Alexander V Nyuchev, Mikhail A Kinzhalov, Pavel S Postnikov","doi":"10.3762/bjoc.21.110","DOIUrl":"10.3762/bjoc.21.110","url":null,"abstract":"<p><p>The arylation of isonitriles by diaryliodonium salts under photoredox conditions has been proposed for the first time. The suggested procedure allows preparing a broad range of benzamides using both symmetric and unsymmetric diaryliodonium salts under mild conditions. A plausible mechanism for the reaction and the selectivity of aryl transfer (in case of unsymmetrical iodonium salts) were studied.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1480-1488"},"PeriodicalIF":2.1,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12302481/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144727153","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":"Heterologous biosynthesis of cotylenol and concise synthesis of fusicoccane diterpenoids.","authors":"Ye Yuan, Zhenhua Guan, Xue-Jie Zhang, Nanyu Yao, Wenling Yuan, Yonghui Zhang, Ying Ye, Zheng Xiang","doi":"10.3762/bjoc.21.111","DOIUrl":"10.3762/bjoc.21.111","url":null,"abstract":"<p><p>A novel strategy for the synthesis of fusicoccane diterpenoids is reported. By harnessing the biosynthetic pathways of brassicicenes and fusicoccins, cotylenol was produced in an engineered <i>Aspergillus oryzae</i> strain. We further achieved the concise synthesis of three fusicoccane diterpenoids, including alterbrassicicene E and brassicicenes A and R in 4 or 5 chemical steps from brassicicene I. This strategy lays the foundation for the preparation of fusicoccane diterpenoids and their analogues for biological studies.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1489-1495"},"PeriodicalIF":2.1,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12302409/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144727151","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":"Copper catalysis: a constantly evolving field.","authors":"Elena Fernández, Jaesook Yun","doi":"10.3762/bjoc.21.109","DOIUrl":"10.3762/bjoc.21.109","url":null,"abstract":"","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1477-1479"},"PeriodicalIF":2.2,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12278110/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681930","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":"Microwave-enhanced additive-free C-H amination of benzoxazoles catalysed by supported copper.","authors":"Andrei Paraschiv, Valentina Maruzzo, Filippo Pettazzi, Stefano Magliocco, Paolo Inaudi, Daria Brambilla, Gloria Berlier, Giancarlo Cravotto, Katia Martina","doi":"10.3762/bjoc.21.108","DOIUrl":"10.3762/bjoc.21.108","url":null,"abstract":"<p><p>The C2-amination of benzoxazole offers wide-ranging potential for substrate expansion and the functionalisation of bioactive compounds. This study presents a green and efficient C-H amination, catalysed by CuCl and CuCl₂, in acetonitrile without acidic, basic or oxidant additives that is accelerated by microwave (MW) irradiation and is completed in 1.5-2 h. A solid Cu(I) catalyst supported on aminated silica made the process cost-effective and heterogeneous, thus simplifying work-up and minimising free copper in solution. The catalyst was found to be regeneratable and reusable for up to eight cycles. The optimised method facilitated the synthesis of various benzoxazole derivatives, demonstrating its versatility and practical applicability.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1462-1476"},"PeriodicalIF":2.2,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12278112/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681931","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":"Wittig reaction of cyclobisbiphenylenecarbonyl.","authors":"Taito Moribe, Junichiro Hirano, Hideaki Takano, Hiroshi Shinokubo, Norihito Fukui","doi":"10.3762/bjoc.21.107","DOIUrl":"10.3762/bjoc.21.107","url":null,"abstract":"<p><p>Cyclobisbiphenylenecarbonyl (CBBC) represents a readily available chiral figure-eight macrocycle containing two carbonyl groups. However, the transformation of the carbonyl groups has been unexplored. Herein, we conducted the Wittig reaction of CBBC with methylenetriphenylphosphorane to furnish two chiral macrocycles containing one or two exocyclic olefin units. Owing to the transformation of carbonyl groups, the resulting products exhibit several unique physical and chemical properties: (1) the enhancement of configurational stability, (2) the appearance of fluorescence, and (3) the reductive carbon-carbon-bond formation between carbonyl and alkene units.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1454-1461"},"PeriodicalIF":2.2,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12278106/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681932","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":"Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications.","authors":"Meng Qiu, Jing Du, Nai-Te Yao, Xin-Yue Wang, Han-Yuan Gong","doi":"10.3762/bjoc.21.106","DOIUrl":"10.3762/bjoc.21.106","url":null,"abstract":"<p><p>Helicenes, a class of non-planar polycyclic aromatic hydrocarbons composed of <i>ortho</i>-fused aromatic rings forming helical architectures, have attracted considerable attention due to their intrinsic chirality and tunable optoelectronic properties. Among them, nitrogen-doped helicenes (azahelicenes) and their heteroatom-co-doped counterparts - such as B/N-, O/N-, S/N-, and Se/N-doped helicenes - have emerged as highly versatile scaffolds for chiral optoelectronic applications. The incorporation of nitrogen enables precise modulation of electronic structures, redox characteristics, and intermolecular interactions, thereby enhancing performance in circularly polarized luminescence (CPL), thermally activated delayed fluorescence (TADF), and chiral sensing. Notably, recent developments have yielded π-extended, structurally robust, and stimuli-responsive azahelicenes exhibiting record-high dissymmetry factors (|<i>g</i> _abs| and |<i>g</i> _lum|), elevated CPL brightness (<i>B</i> _CPL), and efficient integration into CPL-OLEDs and redox-switchable emitters. Boron-nitrogen co-doping strategies, in particular, have facilitated the development of materials with ultra-narrowband emissions, near-unity photoluminescence quantum yields, and electroluminescence dissymmetry factors (|<i>g</i> _EL|) exceeding 10^-3. Likewise, heteroatom co-doping with oxygen, sulfur, or selenium enables spectral tuning across the visible to near-infrared range, improved photostability, and dual-state emissive behavior. In parallel, significant progress in synthetic methodologies - including enantioselective catalysis, electrochemical cyclizations, and multicomponent reaction systems - has granted access to increasingly complex helicene frameworks with well-defined chirality. This review systematically summarizes recent advancements in the synthesis, structural engineering, and chiroptical performance of nitrogen-doped helicenes and their heteroatom-doped derivatives, emphasizing their potential as next-generation chiral optoelectronic materials and outlining future directions toward multifunctional integration and quantum technological applications.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1422-1453"},"PeriodicalIF":2.2,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12256785/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144636065","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}