Non-Aromatic 3<i>H</i>-Pyrroles in the Reaction with Nucleophiles: Is High Reactivity a Myth?
作者:Dmitrii A. Shabalin、Anton V. Kuzmin、Elena Yu. Schmidt、Boris A. Trofimov
DOI:10.1002/ejoc.201900152
日期:2019.3.31
In the present manuscript the results of the first systematic study of 3H‐pyrrolereactivity toward diverse nucleophilic agents are reported. Experimental data and quantum‐chemical calculations allowed to formulate possible research directions in the chemistry of these unique class of non‐aromatic heterocycles.
Synthesis of 5-hydroxy-Δ1-pyrrolines from aryl isoalkyl ketoximes and acetylene in a tuned superbase medium
作者:Dmitrii A. Shabalin、Marina Yu. Dvorko、Elena Yu. Schmidt、Nadezhda I. Protsuk、Boris A. Trofimov
DOI:10.1016/j.tetlet.2016.06.025
日期:2016.7
The reactionbetweenaryl isoalkyl ketoximes and acetylene under atmospheric pressure was applied to the synthesis of 5-hydroxy-Δ1-pyrrolines, containing aromatic substituents at the carbon–nitrogen double bond, in moderate yields. A crucial factor for the synthesis is the accurate tuning of the system basicity to prevent further dehydration of the target compounds to 3H-pyrroles.
3H-Pyrroles as a platform for the catalyst-free construction of dihydropyrrolo[2,1-b]oxazoles: [4 + 2]-cycloaddition vs [2 + 3]-annulation with 1-cyano-3-hydroxyalkynes
作者:Ludmila A. Oparina、Dmitrii A. Shabalin、Nikita A. Kolyvanov、Igor' A. Ushakov、Anastasiya G. Mal'kina、Alexander V. Vashchenko、Boris A. Trofimov
DOI:10.1016/j.tetlet.2018.12.048
日期:2019.1
catalyst-free conditions (20–60 °C) to regio- and stereoselectively afford (Z)-2-(dihydropyrrolo[2,1-b]oxazolylidene)acetonitriles in 62–82% yield, thus evidencing the preference for [2 + 3]-annulation over the [4 + 2]-Diels-Alder alternative. The reaction involves initial nucleophilic addition of the pyrrole moiety at the triple bond followed by tandem ring closure of an anionic intermediate.
非芳香族吡咯异构体3,3-二烷基-2-芳基-3 H-吡咯在温和,无催化剂的条件下(20–60°C)与1-氰基-3-羟基炔烃反应,可进行区域和立体选择性反应以62–82%的产率提供(Z)-2-(二氢吡咯并[ 2,1- b ]恶唑基亚烷基)乙腈,因此证明了[2 + 3]环空取代[4 + 2] -Diels-Alder替代品。该反应包括在三键处吡咯部分的最初亲核加成,随后阴离子中间体的串联闭环。
Diastereoselective synthesis of tetrahydropyrrolo[1,2-<i>d</i>]oxadiazoles from functionalized Δ<sup>1</sup>-pyrrolines and <i>in situ</i> generated nitrile oxides
作者:Evgeniya E. Ivanova、Dmitrii A. Shabalin、Igor’ A. Ushakov、Alexander V. Vashchenko、Elena Yu. Schmidt、Boris A. Trofimov
DOI:10.1039/d2ob02230c
日期:——
been synthesized in good-to-excellent yields via the cycloaddition of nitrile oxides (in situ generated from aldoximes) to readily accessible functionalized Δ1-pyrrolines. The reaction proceeds smoothly at room temperature in a two-phase system in the presence of sodium hypochloride as an oxidant to diastereoselectively afford pharmaceutically prospective 1,2,4-oxadiazolines fused with a five-membered
四氢吡咯并 [1,2- d ] 恶二唑通过将氧化腈(由醛肟原位生成)环加成到易于获得的功能化 Δ 1 -吡咯啉,以良好到极好的收率合成。在次氯酸钠作为氧化剂的存在下,反应在室温下在两相系统中顺利进行,以非对映选择性地提供具有药学前景的与五元环稠合的 1,2,4-恶二唑啉。该反应可耐受多种底物,包括具有氧化剂敏感官能团和竞争性反应位点的底物。