Tetrahedron最新文献_第10页

Synthesis of tri/difluoromethyl pyrazoles by [3+2] cycloaddition of tri/difluoroacetohydrazonoyl bromides with vinyl acetates 三/二氟乙酰基肼溴化物与乙酸乙烯酯的 [3+2] 环加成法合成三/二氟甲基吡唑

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-31 DOI: 10.1016/j.tet.2024.134241

引用次数: 0

Photocatalytic and electrocatalytic α-C–H functionalization of tertiary amines 叔胺的光催化和电催化 α-C-H 功能化

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-31 DOI: 10.1016/j.tet.2024.134234

{"title":"Photocatalytic and electrocatalytic α-C–H functionalization of tertiary amines","authors":"","doi":"10.1016/j.tet.2024.134234","DOIUrl":"10.1016/j.tet.2024.134234","url":null,"abstract":"<div><p>We present a comprehensive review of the photochemical and electrochemical methodologies employed in the α-C–H functionalization of tertiary amines. The discussion starts with an introduction to α-C–H functionalization strategies, emphasizing the generation of radical species. The iminium ion and α-aminoalkyl radical are identified as key intermediates interacting with various organic functional groups. The review is divided into two main sections: photocatalytic and electrocatalytic α-C–H functionalization. In the photocatalytic section, we classify the functionalization into photocatalyst-mediated and photocatalyst-free approaches. Photocatalyst-mediated functionalization is further categorized into four mechanisms: Nucleophilic substitution, Transition-metal complexing, Giese-type reaction, and Radical-radical cross-coupling. Photocatalyst-free functionalization focuses on the direct excitation of the substrate and the EDA complex pathways, with particular emphasis on the latter. The electrocatalytic section explores both direct and indirect electrolysis techniques, highlighting the role of redox mediators in the indirect approach. Each section critically analyzes recent research examples from the past five years. This review aims to elucidate the current state of α-C–H functionalization research and suggest promising directions for future investigations.</p></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142128625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MPC@But-SO3H a mesoporous heterogeneous organocatalyst in one-pot tandem synthesis of dihydroindeno[1,2-b]pyrrole derivatives 介孔异质有机催化剂 MPC@But-SO3H 在二氢茚并[1,2-b]吡咯衍生物的一锅串联合成中的应用

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134233

{"title":"MPC@But-SO3H a mesoporous heterogeneous organocatalyst in one-pot tandem synthesis of dihydroindeno[1,2-b]pyrrole derivatives","authors":"","doi":"10.1016/j.tet.2024.134233","DOIUrl":"10.1016/j.tet.2024.134233","url":null,"abstract":"<div><div>A sustainable, metal-free, and highly efficient protocol for the synthesis of dihydroindeno[1,2-b]pyrrole derivatives via a tandem one-pot three-component reaction in aqueous medium at room temperature using an effective and reusable mesoporous heterogeneous organocatalyst, MPC@But-SO<sub>3</sub>H has been developed. MPC@But-SO<sub>3</sub>H was easily synthesized using a melamine-based covalent organic polymer and 1,4-butane sultone. The organocatalyst was well characterized by numerous spectroscopic techniques such as Fourier Transform Infrared (FTIR), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), Powder X-ray diffraction (PXRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), elemental mapping, and Thermal Gravimetric (TG) analyses. The catalyst displayed excellent catalytic potential, high thermochemical stability, and reusability for up to eight catalytic cycles. It offered the title compounds in excellent yields (˃90%) in a short reaction time (9-14 min). The synthesized compounds were characterized through FTIR, <sup>1</sup>H, and <sup>13</sup>C Nuclear Magnetic Resonance (NMR), and the molecular structure of 2-(benzylamino)-3a,8b-dihydroxy-1-methyl-3-nitro-3a,8b-dihydroindeno[1,2-b]pyrrol-4(1H)-one <strong>(4a)</strong> was confirmed by the Single Crystal XRD (SC-XRD) analysis. The key features of the present protocol include the use of water as a green solvent, zero involvement of any metal, sustainable reaction conditions, easy catalyst recovery, and a simple work-up procedure. The calculations for green metrics parameters further supported the greenness and sustainability of the protocol.</div></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142318599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Catalytic merits of Ni0.6Zn0.4Fe2O4/f-MWCNTS–CS–Asp/Ni2+ for tailoring 1H-benzo [4,5] imidazo [1,2-b] [1,2,4]triazepine motifs through green domino strategy 通过绿色多米诺策略，Ni0.6Zn0.4Fe2O4/f-MWCNTS-CS-Asp/Ni2+ 在定制 1H 苯并 [4,5] 咪唑并 [1,2-b] [1,2,4] 三氮杂卓基团方面的催化优势

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134231

{"title":"Catalytic merits of Ni0.6Zn0.4Fe2O4/f-MWCNTS–CS–Asp/Ni2+ for tailoring 1H-benzo [4,5] imidazo [1,2-b] [1,2,4]triazepine motifs through green domino strategy","authors":"","doi":"10.1016/j.tet.2024.134231","DOIUrl":"10.1016/j.tet.2024.134231","url":null,"abstract":"<div><p>The magnetic nano catalyst mediated synthesis of heterocycles is one of the most fascinating fields of chemistry due to its proven applicability in high-efficiency, eco-friendly and recyclable heterogeneous catalytic system. In order to design a novel Ni<sub>0.6</sub>Zn<sub>0.4</sub>Fe<sub>2</sub>O<sub>4</sub>/f-MWCNTs–CS–Asp/Ni<sup>2+</sup> magnetic heterogeneous catalyst, Ni<sub>0.6</sub>Zn<sub>0.4</sub>Fe<sub>2</sub>O<sub>4</sub>-decorated multi walled CNTs were modified with crosslinked chitosan with <span>l</span>-aspartic acid entrapped Ni<sup>2+</sup> nanoparticles. This nano catalyst showed significant catalytic activity in the synthesis of biologically potent novel seven membered heterocycles embracing fused 1H-benzo [4,5]imidazo [1,21,2-b][1,2,4]triazepine skeleton. Owing to its interesting structure and being an important pharmacophore fragment, it was endeavored to exploit its synthesis. For the first time considering an exquisite and accomplishable access to construct (Kaur et al., 2021; Jiang et al., 2006; Stern, 1980) [1,2,4]triazepine framework. In addition, the structures of synthesized heterocycles and morphology of nano catalyst were corroborated on the basis of various spectroscopical and microscopical techniques. Furthermore, employing ultrasonication as energy source in the synthesis of magnetic nano catalyst employing 3R's (reduce, recycle and reuse), mild reaction conditions with appreciable yield along with no consumption and production of hazardous chemicals put it under the umbrella of green and sustainable approach.</p></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142128505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A decade update on synthesis of bicyclic β-lactams and their transformation into synthetically/biologically relevant carbocyclic and heterocyclic moieties 双环 β-内酰胺合成及其转化为合成/生物学相关碳环和杂环分子的十年最新进展

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134230

引用次数: 0

Synthesis of pyrrolo[1,2-a]quinoline and pyrrolo[1,2-b]isoquinoline derivatives via intramolecular acylation 通过分子内酰化合成吡咯并[1,2-a]喹啉和吡咯并[1,2-b]异喹啉衍生物

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134224

引用次数: 0

Copper-catalyzed three-component reaction to construct thietane ring using elemental sulfur 铜催化三组分反应，利用元素硫构建硫杂环

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134226

引用次数: 0

Repurposing Mander's reagent for the first direct carbonyl deoxycyanation: Synthesis of oxoalkenenitriles from 1,3-diketones 将 Mander 试剂重新用于首次直接羰基脱氧氰化：从 1,3-二酮合成氧化烯腈

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-30 DOI: 10.1016/j.tet.2024.134237

{"title":"Repurposing Mander's reagent for the first direct carbonyl deoxycyanation: Synthesis of oxoalkenenitriles from 1,3-diketones","authors":"","doi":"10.1016/j.tet.2024.134237","DOIUrl":"10.1016/j.tet.2024.134237","url":null,"abstract":"<div><p>The deoxycyanation of ketones is an uncommon reaction. Recently, we demonstrated that alkyl cyanoformates, such as methyl cyanoformate (Mander's reagent) or ethyl cyanoformate, can perform deoxycyanation on 1,3-diketones to deliver oxoalkenenitriles directly. This represents a significant departure from the typical reactivity of these reagents, which are predominantly used for the synthesis of β-ketoesters (α-acylation). By transitioning from lithium bases to amine-based bases, the selectivity of the acylation shifts from carbon to oxygen, yielding an enol carbonate intermediate. Density Functional Theory (DFT) investigations and <em>in vitro</em> experiments corroborate the synthetic outcome, namely, the synthesis of oxonitriles via deoxycyanation. The reaction mechanism was studied, revealing a series of sequential additions and eliminations consistent with the mechanistic proposal for the generation of a major byproduct, which poses one of the main drawbacks of this method. Although this approach was proven to be non-general, it represents the first direct synthesis of oxoalkenenitriles through a deoxycyanation process, thereby deviating from the conventional <em>C</em>-selective applications of alkyl cyanoformates.</p></div>","PeriodicalId":437,"journal":{"name":"Tetrahedron","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0040402024004174/pdfft?md5=ae1ae224b0326cbd431cb05d1fc39b1f&pid=1-s2.0-S0040402024004174-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Asymmetric conjugate 1,6-addition of organocuprates to N-dienoyl oxazolidinones 有机铜酸盐与 N-二烯酰基噁唑烷酮的不对称共轭 1,6-加成反应

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-28 DOI: 10.1016/j.tet.2024.134232

引用次数: 0

Light-promoted AIBN-catalyzed oxidative cleavage of aryl olefins to aryl ketones 光促进 AIBN 催化芳基烯烃氧化裂解为芳基酮

IF 2.1 3区化学

Tetrahedron Pub Date : 2024-08-28 DOI: 10.1016/j.tet.2024.134211

引用次数: 0