Tetrahedron chemPub Date : 2024-03-01Epub Date: 2024-01-23DOI: 10.1016/j.tchem.2024.100063
Magdalena Piringer , Lotte Stockhammer , Lukas Vogl , David Weinzierl , Paul Zebrowski , Mario Waser
{"title":"Enantioselective α-heterofunctionalization reactions of catalytically generated C1-Lewis base enolates","authors":"Magdalena Piringer , Lotte Stockhammer , Lukas Vogl , David Weinzierl , Paul Zebrowski , Mario Waser","doi":"10.1016/j.tchem.2024.100063","DOIUrl":"10.1016/j.tchem.2024.100063","url":null,"abstract":"<div><p>Chiral Lewis base (LB) organocatalysis has emerged as a powerful covalent catalysis concept which allows for highly selective asymmetric C–C and C-heteroatom bond formations. Considering significant recent progress in the development of strategies to access α-heterofunctionalized carboxylic acid derivatives under chiral LB catalysis, we wish to summarize the most significant concepts and advances in this field within this mini review now.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"9 ","pages":"Article 100063"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X24000020/pdfft?md5=6ceeda1e31c0a2f2f20075a48cde9727&pid=1-s2.0-S2666951X24000020-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139631852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Supramolecular hydrogelation triggered by a gold catalyst","authors":"Tomoya Yamamoto , Akiko Nakamura , Akari Mukaimine , Katsunori Tanaka","doi":"10.1016/j.tchem.2023.100058","DOIUrl":"10.1016/j.tchem.2023.100058","url":null,"abstract":"<div><p>Supramolecular gels formed by self-assembly of low-molecular-weight gelators have been attracting attention as biomaterials. In particular, various triggers for supramolecular hydrogelation, such as enzymatic reactions, have been developed to selectively induce the formation of gels at targeted sites <em>in vivo</em>. However, there are still limitations to the methods for triggering self-assembly, such as the selectivity of hydrogelation at targeted sites. Here, we report the first example of a low-molecular-weight hydrogelator whose gelation is triggered by catalytic amount of transition-metal complexes. This gelator consists of a substrate structure for a ring-closing reaction catalyzed by gold, and this reaction transforms the morphology of fibrils to induce hydrogelation in the presence of peptide additives. This novel trigger for hydrogelation will expand the applicability of a low-molecular-weight gelator <em>in vivo</em> when used with biocompatible metal catalysts.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"9 ","pages":"Article 100058"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000244/pdfft?md5=6872d804de8e5cf9bc4845ce5bf65596&pid=1-s2.0-S2666951X23000244-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2024-03-01Epub Date: 2024-02-24DOI: 10.1016/j.tchem.2024.100067
Guizhou Yue , Bo Liu
{"title":"The photoinduced electron transfer (PET) reactions of silyl ethers and their application","authors":"Guizhou Yue , Bo Liu","doi":"10.1016/j.tchem.2024.100067","DOIUrl":"https://doi.org/10.1016/j.tchem.2024.100067","url":null,"abstract":"<div><p>Photocatalyzed organic reaction has been greatly developed and applied at the last 20 years, because photochemical synthesis is an efficiently green synthetic strategy, featuring simple operation, high chemical selectivity and low price <em>etc</em>. Meanwhile, organosilicon reagents have been widely used and developed in the field of organic synthesis since they were discovered. Photocatalyzed reactions of organosilicon compounds, especially silyl ethers, have taken advantages of mild condition, good selectivity and atom economy and been performed in synthesizing silicon-containing molecules and carbon skeleton molecules which were difficultly acquired by the traditional approaches. This review mainly introduced the reaction of silyl enol ethers, cyclopropyl silyl ethers, silyl acetals, silyl ethers and ketene silyl acetals via PET triggered by sensitizers/co-sensitizers, photocatalysts, electron donor-acceptor (EDA) complex, no photocatalysts and sensitizers and so on.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"9 ","pages":"Article 100067"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X24000068/pdfft?md5=128202f5a0a2eab6a3bfa5ac519f3464&pid=1-s2.0-S2666951X24000068-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139993019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2024-03-01Epub Date: 2024-01-14DOI: 10.1016/j.tchem.2023.100055
Richard J.K. Taylor, William P. Unsworth
{"title":"Ynones in dearomative spirocyclisation processes; a review","authors":"Richard J.K. Taylor, William P. Unsworth","doi":"10.1016/j.tchem.2023.100055","DOIUrl":"10.1016/j.tchem.2023.100055","url":null,"abstract":"<div><p>This review concentrates on our research into the discovery of novel ynone-based dearomative spirocyclisation processes, whilst placing the new chemistry into the context of existing knowledge. The genesis of the research programme, the development of efficient synthetic routes to prepare the novel natural products spirobacillene A (<strong>1</strong>) and spirobacillene B (<strong>2</strong>), utilised the dearomative spirocyclisation of indole ynones. This stimulated a much wider study to explore the reactivity of ynones in dearomative spirocyclisation processes more generally. Routes to generate a wide range of spirocycles were subsequently developed, with dearomative reactions of ynones tethered to indoles, benzofurans, benzisoxazoles, pyrroles, pyridines, isoquinolines, pyrazines, cyclic ketimines, and anisoles all discussed herein, with these reactions initiated by catalytic Ag(I), Cu(II), Pd(0), visible light and many other reagents. Asymmetric variants of some of the reactions are also discussed, as is further elaboration of the spirocyclic products to give carbazoles, quinolones, polycycles and other useful synthetic building blocks. Finally, applications of the new methodology in natural product synthesis (<em>e.g</em>. spirobacillene A, lasubine II and indolizidine 209D) are described.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"9 ","pages":"Article 100055"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000219/pdfft?md5=b00a306f15e6e5497d6dca88968ed40d&pid=1-s2.0-S2666951X23000219-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139538358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2024-03-01Epub Date: 2023-12-19DOI: 10.1016/j.tchem.2023.100060
Stephanie Lee, Tilo Söhnel, Jonathan Sperry
{"title":"Biomimetic synthetic studies on the hicksoane alkaloids","authors":"Stephanie Lee, Tilo Söhnel, Jonathan Sperry","doi":"10.1016/j.tchem.2023.100060","DOIUrl":"10.1016/j.tchem.2023.100060","url":null,"abstract":"<div><p>The hicksoane alkaloids contain an unusual propane-2,2-diamine unit embedded within a 1,3,6-triazocane, the only natural product known to possess this eight-membered heterocycle. Herein, we report the results examining a biosynthesis proposal that this heterocycle emerges from a late-stage reaction of a dipeptide with acetone. Ile-Trp-CONH<sub>2</sub> and Trp-Ile-CONH<sub>2</sub> dipeptides were trialled as substrates; in both cases, the intermediate iminium ion did not engage with the primary amide to form the triazocane, reacting instead to generate an imidazolidinone and a β-carboline, respectively. The results from this study infer the triazocane present in these alkaloids is unlikely to be biosynthesised by the late-stage reaction of a dipeptide with biogenic acetone.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"9 ","pages":"Article 100060"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000268/pdfft?md5=2d76cab1d1764bcccf39c005e98c1601&pid=1-s2.0-S2666951X23000268-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139020123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2023-12-01Epub Date: 2023-09-07DOI: 10.1016/j.tchem.2023.100048
Zhongyue Lu, Xuling Chen, Pengfei Li
{"title":"Organocatalytic Regio- and Enantioselective (3+3)-Annulation of 2-(4H-Benzo[d][1,3]oxazin-4-yl)acrylates with 2,4-Dihydro-3H-pyrazol-3-ones","authors":"Zhongyue Lu, Xuling Chen, Pengfei Li","doi":"10.1016/j.tchem.2023.100048","DOIUrl":"10.1016/j.tchem.2023.100048","url":null,"abstract":"<div><p>A chiral sulfonamide-phosphine catalyzed regio- and enantioselective (3 + 3)-annulation of 2-(4<em>H</em>-benzo[<em>d</em>][1,3]oxazin-4-yl)acrylates with 2,4-dihydro-3<em>H</em>-pyrazol-3-ones has been established, affording a wide range of such 1,4,5,6-tetrahydropyrano [2,3-<em>c</em>]pyrazole-containing carboxylates in generally high yields (61–96%) with high diastereo- and enantioselectivities (8:1->20:1 dr, 85–95% ee). Based on several control experiments, a reaction mechanism was proposed. Importantly, the work represents the first example of using benzoxazinyl acrylates as three-atom synthons, which enriches the chemistry of benzoxazinyl acrylates.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"8 ","pages":"Article 100048"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49068883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Recent developments in transition metal-catalyzed asymmetric borrowing hydrogen catalysis","authors":"Nidhi Garg, Ishika Agrawal, Dhananjay Satav, Doppalapudi Vineet Kumar, Basker Sundararaju","doi":"10.1016/j.tchem.2023.100054","DOIUrl":"https://doi.org/10.1016/j.tchem.2023.100054","url":null,"abstract":"<div><p>Asymmetric Borrowing Hydrogen (BH) catalysis is a versatile, one-step approach for synthesizing enantioenriched amines/carbonyl derivatives from biomass-derived oxidized hydrocarbons with water as the sole by-product. These valuable chiral moieties are ubiquitous in natural products, fragrances, agrochemicals, and pharmaceuticals; hence, efficient methodologies that can directly form C–C and C–N bonds to diversify the synthetic utility are highly desired. Over the last decade, numerous contributions involving noble metals have been documented in this area, which largely relies on the choice of a suitable transition metal catalyst that facilitates a succession of oxidation/reduction steps. Only very recently, 3d metals were utilized for C–C and C–N bond formation in an asymmetric manner using the BH strategy. This article describes the current state-of-the-art for controlling the stereochemistry in the formation of a new stereogenic center <em>via</em> multiple catalysis, rational ligand design, <em>etc</em>. Several other strategies are outlined, such as asymmetric reductive functionalization, dynamic kinetic resolution, enantioconvergent processes, <em>etc</em>. New chiral catalysts based on 3d metals are anticipated to arise and find applications in the field of asymmetric borrowing hydrogen catalysis.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"8 ","pages":"Article 100054"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000207/pdfft?md5=c87883cd936f5a5efe186b0f8c5a6c25&pid=1-s2.0-S2666951X23000207-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138471694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2023-12-01Epub Date: 2023-10-24DOI: 10.1016/j.tchem.2023.100051
Wen-Da Chen , Liang Cheng
{"title":"Synthesis and application of stimulus-triggered cyclic caged oligonucleotides for gene expression regulation","authors":"Wen-Da Chen , Liang Cheng","doi":"10.1016/j.tchem.2023.100051","DOIUrl":"https://doi.org/10.1016/j.tchem.2023.100051","url":null,"abstract":"<div><p>Cyclically caged oligonucleotides are a distinct category of altered biomacromolecules. They are created by incorporating caged motifs into oligonucleotides and subsequently undergoing cyclization through chemical or enzymatic means. The cyclic structure of these oligonucleotides significantly affects their characteristics and functionality, resulting in enhanced ribonuclease stability and loss of the ability to form complementary base pairs. However, when a specific stimulus is introduced, the ring structure can be deactivated, thereby restoring the oligonucleotide's function. This enables precise regulation of gene expression in both space and time by triggering a designated stimulus. In recent years, various cyclization strategies have been employed to modify antisense oligodeoxynucleotides, siRNAs, and gRNAs. This review will delve into the main synthesis methods used to generate cyclically caged oligonucleotides in the past decade. Moreover, we will explore the applications of these oligonucleotides in gene expression regulation, encompassing gene silencing and gene editing. This offers a valuable tool for comprehending the role of genes in the processes of biological growth and development.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"8 ","pages":"Article 100051"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000177/pdfft?md5=4f789c5fdb17e0af62268e3b37691309&pid=1-s2.0-S2666951X23000177-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92046279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2023-12-01Epub Date: 2023-11-10DOI: 10.1016/j.tchem.2023.100053
Maurizio Chiminelli, Gabriele Scarica, Davide Balestri, Luciano Marchiò, Nicola Della Ca’, Giovanni Maestri
{"title":"The visible-light-promoted intermolecular para-cycloadditions of allenamides on naphthalene","authors":"Maurizio Chiminelli, Gabriele Scarica, Davide Balestri, Luciano Marchiò, Nicola Della Ca’, Giovanni Maestri","doi":"10.1016/j.tchem.2023.100053","DOIUrl":"https://doi.org/10.1016/j.tchem.2023.100053","url":null,"abstract":"<div><p>The preparation of bridged bicyclooctadienes through the dearomatization of simple arenes is an interesting synthetic tool to access a vast chemical space of elegant molecular architectures from a wide range of simple and cheap building blocks. However, the energetic toll due to the loss of the aromatic stabilization has greatly limited the development of <em>para</em>-cycloadditions, especially with respect to intermolecular processes. We report herein the first general approach for the selective dearomatization of simple naphthalene. The visible-light-promoted reaction occurs under mild conditions over an ample range of substrates and it involves the initial sensitization of an acylallenamide. Moreover, complete control on the difunctionalization of either the internal or the terminal C–C double bond is observed depending on the substrate functionalization.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"8 ","pages":"Article 100053"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2666951X23000190/pdfft?md5=70a4637a62813cd5b00c2a5e77e71d79&pid=1-s2.0-S2666951X23000190-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134656667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tetrahedron chemPub Date : 2023-12-01Epub Date: 2023-08-22DOI: 10.1016/j.tchem.2023.100045
Sara González , Dario Del Carratore , Ricardo J. Maza , Elena Fernández
{"title":"The seriatim Cu(I) activation of 1,1,1′,1′-tetrapinacolborylethane to prospective ring closing","authors":"Sara González , Dario Del Carratore , Ricardo J. Maza , Elena Fernández","doi":"10.1016/j.tchem.2023.100045","DOIUrl":"10.1016/j.tchem.2023.100045","url":null,"abstract":"<div><p>The synthesis and characterization of 1,1,1′1′-tetrapinacolborylethane is conducted to study the functionalization of that densely borylated small molecules through Cu-catalyzed coupling with allyl halides. A second Cu-catalyzed allylic alkylation of the homoallyl triboronate products gave access to mixed dihomoallyl diboronates. The intramolecular concatenated allylic alkylation version produced methylenecyclopentane-1,2-dipinacolboronic ester with 2:1 diastereoselection on the <em>trans</em>-diastereoisomer.</p></div>","PeriodicalId":74918,"journal":{"name":"Tetrahedron chem","volume":"8 ","pages":"Article 100045"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44117365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}