{"title":"Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C-N bond axial chirality.","authors":"Natsume Akimoto, Kaho Takaya, Yoshio Kasashima, Kohei Watanabe, Yasushi Yoshida, Takashi Mino","doi":"10.3762/bjoc.21.83","DOIUrl":"10.3762/bjoc.21.83","url":null,"abstract":"<p><p>In this study, we implemented the P,olefin-type chiral ligand (a<i>R</i>)-(-)-<b>6</b>, which contains a cyclohexyl group and a cinnamoyl group on the nitrogen atom, in the Pd-catalyzed asymmetric allylic amination of allylic esters with isatin derivatives <b>11</b> as nucleophiles. The reaction proceeds efficiently, yielding the products (<i>S</i>)-<b>13</b> with good-to-high enantioselectivity. A scale-up reaction was also successfully conducted at a 1 mmol scale. Additionally, when malononitrile was added to the resulting product (<i>S</i>)-<b>13a</b> in the presence of FeCl<sub>3</sub> as the catalyst, the corresponding malononitrile derivative (<i>S</i>)-<b>16</b> was obtained without any loss in optical purity.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1018-1023"},"PeriodicalIF":2.2,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117205/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172561","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}
Ruben Manuel Figueira de Abreu, Robin Tiedemann, Peter Ehlers, Peter Langer
{"title":"Synthesis of pyrrolo[3,2-<i>d</i>]pyrimidine-2,4(3<i>H</i>)-diones by domino C-N coupling/hydroamination reactions.","authors":"Ruben Manuel Figueira de Abreu, Robin Tiedemann, Peter Ehlers, Peter Langer","doi":"10.3762/bjoc.21.82","DOIUrl":"10.3762/bjoc.21.82","url":null,"abstract":"<p><p>A variety of pyrrolo[3,2-<i>d</i>]pyrimidine-2,4(3<i>H</i>)-diones were prepared by a combination of Sonogashira reaction and subsequent cyclization by domino C-N coupling/hydroamination reaction. The optical properties (UV-vis absorption and fluorescence) depend on the substitution pattern of the compounds.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"1010-1017"},"PeriodicalIF":2.2,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117214/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172591","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":"Recent total synthesis of natural products leveraging a strategy of enamide cyclization.","authors":"Chun-Yu Mi, Jia-Yuan Zhai, Xiao-Ming Zhang","doi":"10.3762/bjoc.21.81","DOIUrl":"10.3762/bjoc.21.81","url":null,"abstract":"<p><p>Enamides are distinctive amphiphilic synthons that can be strategically incorporated into cyclization reactions. The iminium species generated from enamides via nucleophilic addition or substitution are capable of engaging in further electrophilic additions or isomerization processes. Exploiting the multiple reactivities of enamides facilitates the development of diverse cyclization modes that provide entries to various <i>N</i>-heterocycles, some of which serve as key structural motifs in natural alkaloids. This review highlights recent advancements in enamide-based cyclization reactions, including enamide-alkyne cycloisomerization, [3 + 2] annulation, and polycyclization, with a particular emphasis on their pivotal role as a strategy in the total synthesis of natural products.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"999-1009"},"PeriodicalIF":2.2,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117209/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172585","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}
Daniel Straub, Markus Gross, Mona E Arnold, Julia Zolg, Alexander J C Kuehne
{"title":"On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals.","authors":"Daniel Straub, Markus Gross, Mona E Arnold, Julia Zolg, Alexander J C Kuehne","doi":"10.3762/bjoc.21.80","DOIUrl":"10.3762/bjoc.21.80","url":null,"abstract":"<p><p>Organic radicals with light-emitting properties and exceptional stability offer exciting opportunities to address spin-statistical limitations in organic electronics and advance quantum technologies. These radicals, acting as small molecular magnets, exhibit sensitivity to minute magnetic fields and can be tailored with diverse spin centers, making them ideal for spin-optical interfaces, representing key components in quantum communication systems. Furthermore, their ability to form organized, higher-dimensional assemblies presents a promising avenue for overcoming scalability challenges in quantum technologies. Despite their potential, achieving high luminescence quantum yields has largely been limited to donor-functionalized monoradicals, and a detailed understanding of the luminescent behavior of open-shell organic molecules remains elusive. This review delves into the photoluminescent properties and spin ground states of trityl-based mono-, di-, and multiradicals, examining the strategies employed to enhance their performance. Additionally, we review predictive methods for determining the luminescence and spin states of radicals, highlighting critical unresolved questions that must be addressed to unlock the full potential of trityl-based radicals in advanced technological applications.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"964-998"},"PeriodicalIF":2.2,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117217/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172559","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}
Benedek Batizi, Patrik Pollák, András Dancsó, Péter Keglevich, Gyula Simig, Balázs Volk, Mátyás Milen
{"title":"Studies on the syntheses of β-carboline alkaloids brevicarine and brevicolline.","authors":"Benedek Batizi, Patrik Pollák, András Dancsó, Péter Keglevich, Gyula Simig, Balázs Volk, Mátyás Milen","doi":"10.3762/bjoc.21.79","DOIUrl":"10.3762/bjoc.21.79","url":null,"abstract":"<p><p>A new total synthesis of the β-carboline alkaloid brevicarine is disclosed. The synthesis was carried out starting from an aromatic triflate key intermediate, allowing the introduction of various substituents into position 4 of β-carboline by cross-coupling reactions. Thanks to its scalability, this novel approach ensures a broad accessibility to the target compound for potential pharmacological measurements. Using detailed NMR studies, the NMR signals have been assigned for both the base and its dihydrochloride salt for further confirming their structures. A new synthesis of the related alkaloid brevicolline was also attempted from the same intermediate. However, after successful coupling of β-carboline with <i>N</i>-methylpyrrole, the trials to saturate the pyrrole ring under various conditions led to unexpected reactions: reduction of ring A of the β-carboline skeleton or trifluoroethylation of the pyrrole moiety occurred, leading to interesting and potentially useful derivatives.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"955-963"},"PeriodicalIF":2.2,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117210/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172587","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}
Shyam Sathyamoorthi, Appasaheb K Nirpal, Dnyaneshwar A Gorve, Steven P Kelley
{"title":"Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes.","authors":"Shyam Sathyamoorthi, Appasaheb K Nirpal, Dnyaneshwar A Gorve, Steven P Kelley","doi":"10.3762/bjoc.21.78","DOIUrl":"10.3762/bjoc.21.78","url":null,"abstract":"<p><p>We present the first examples of alkene amino-sulfonoxylation reactions that leverage the unique reactivity of carbamate tethered <i>N</i>-alkoxy nitrenium ions. In almost all cases examined, the reactions deliver product with exquisite regioselectivity and diastereoselectivity. The protocols followed are operationally very simple and only use commercial I(III) reagents and sulfonic acids, amounting to a metal-free protocol for alkene amino-oxygenation. No special precautions need be taken to exclude air or ambient moisture, and the products are amenable to further transformations.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"947-954"},"PeriodicalIF":2.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117213/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172555","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":"Study of tribenzo[<i>b</i>,<i>d</i>,<i>f</i>]azepine as donor in D-A photocatalysts.","authors":"Katy Medrano-Uribe, Jorge Humbrías-Martín, Luca Dell'Amico","doi":"10.3762/bjoc.21.76","DOIUrl":"10.3762/bjoc.21.76","url":null,"abstract":"<p><p>Since the discovery of donor-acceptor (D-A) type molecules in the field of materials science, they have found great applicability in the field of photocatalysis. Most of these compounds are based on complex D-A-D structures or multi-D-A systems, such as 4CzIPN. Whereas these systems have been widely studied and applied as photocatalysts, simpler D-A structures remain less explored. Nevertheless, the simplicity of D-A structures makes them the ideal structures to further understand the structure-property relationship of D-A molecules for optimizing their photocatalytic performance by simpler modification of the different D-A subunits. In particular, D-A structures featuring sulfur-based acceptors and nitrogen donors have gained increasing attention for their use as photoredox catalysts. This study introduces a new family of D-A molecules by exploring various sulfur-based acceptors and nitrogen donors, including a novel tribenzo[<i>b,d,f</i>]azepine (TBA) unit and 5<i>H</i>-dibenz[<i>b,f</i>]azepine (IMD). Our findings demonstrate that these simple D-A structures exhibit promising photocatalytic properties, comparable to those of more complex D-A-D systems.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"935-944"},"PeriodicalIF":2.2,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117207/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172589","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}
Zhiyang Zhang, Jialei Hu, Hanfeng Ding, Li Zhang, Peirong Rao
{"title":"A convergent synthetic approach to the tetracyclic core framework of khayanolide-type limonoids.","authors":"Zhiyang Zhang, Jialei Hu, Hanfeng Ding, Li Zhang, Peirong Rao","doi":"10.3762/bjoc.21.75","DOIUrl":"10.3762/bjoc.21.75","url":null,"abstract":"<p><p>A convergent approach for the enantioselective construction of an advanced intermediate containing the [5,5,6,6]-tetracyclic core framework of the khayanolide-type limonoids was described. The strategy features an acylative kinetic resolution of the benzylic alcohol, a 1,2-Grignard addition and an AcOH-interrupted Nazarov cyclization.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"926-934"},"PeriodicalIF":2.2,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117208/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144172581","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}
Muhammad Hasan, Anatoly A Peshkov, Syed Anis Ali Shah, Andrey Belyaev, Chang-Keun Lim, Shunyi Wang, Vsevolod A Peshkov
{"title":"Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines.","authors":"Muhammad Hasan, Anatoly A Peshkov, Syed Anis Ali Shah, Andrey Belyaev, Chang-Keun Lim, Shunyi Wang, Vsevolod A Peshkov","doi":"10.3762/bjoc.21.74","DOIUrl":"https://doi.org/10.3762/bjoc.21.74","url":null,"abstract":"<p><p>A silver(I) triflate-catalyzed post-Ugi assembly of novel pyrazolo[1,5-<i>a</i>][1,4]diazepine scaffolds is reported offering high yields (up to 98%) under mild conditions. The synthetic sequence involves the Ugi four-component reaction (U4CR) of pyrazole-3-carbaldehydes, primary amines, 3-substituted propiolic acids, and isocyanides, followed by a silver(I) triflate-catalyzed intramolecular heteroannulation of the resulting pyrazole-tethered propargylamides occurring in a 7-<i>endo</i>-<i>dig</i> fashion. The approach is scalable and tolerates a diverse range of substitution patterns.</p>","PeriodicalId":8756,"journal":{"name":"Beilstein Journal of Organic Chemistry","volume":"21 ","pages":"915-925"},"PeriodicalIF":2.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12067096/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143963940","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}