Abstract
<p><strong>Objectives. </strong>To prepare new N-(1,2,3,4-tetrahydroquinolin-4-yl) pyrrolidin-2-one molecules and to characterize them by spectroscopic methods. <strong>Materials and methods. </strong>All reagents were purchased from Aldrich, commercial grade. The purity of the products and the composition of the reaction mixtures were monitored by thin layer chromatography over Silufol UV<sub>254</sub> chromatoplates (0.25 mm). Product isolation and purification were performed by column chromatography (SiO<sub>2</sub>), using ethyl acetate. <strong>Results.</strong> Preparation of new N-(2-nitrophenyl-1,2,3,4-tetrahydroquinolin-4-yl) pyrrolidin-2-ones has been achieved via the one-pot synthesis, based on a BiCl<sub>3</sub>-catalyzed imino Diels-Alder cycloaddition reaction of toluidine, N-vinylpyrrolidin-2-one and 4-nitro- or 3-nitrobenzaldehydes. The structure of the pyrrolidine derivatives was confirmed by <sup>1</sup>H nmr and <sup>13</sup>C nmr studies, in addition to inverse-detected 2D NMR experiments and monocrystal X-ray diffraction. <strong>Conclusions. </strong>An efficient, economic, and fast synthetic route (multi-component imino Diels-Alder reaction) was employed in the construction of several new tetrahydroquinoline derivatives, useful and attractive rigid skeleton with well-defined stereochemistry.</p> <p> </p> <p><strong>Key words: </strong>tetrahydroquinoline derivatives, N-substituted pyrrolidin-2-ones, three component imino Diels-Alder reaction, one-pot synthesis.</p>
Highlights
Quinoline and tetrahydroquinoline structures are an essential feature of many natural products
Polyfunctionalized tetrahydroquinolines (THQs) are molecules of great interest in organic synthesis since many natural products present this system in their structure, and because they exhibit diverse biological activities [5,6,7,8,9]
An efficient route in the preparation of THQs is the acid-catalyzed Povarov reaction that is classified as imino Diels-Alder cycloaddition [11,12,13] and permits the condensation of anilines, aldehydes, and electron-rich alkenes using acidic catalysts under mild conditions to achieve the obtainment of new substituted tetrahydroquinolines
Summary
Quinoline and tetrahydroquinoline structures are an essential feature of many natural products These heterocycles play a key role in heterocyclic and medicinal chemistry. Polyfunctionalized tetrahydroquinolines (THQs) are molecules of great interest in organic synthesis since many natural products present this system in their structure, and because they exhibit diverse biological activities [5,6,7,8,9]. Besides their notorious bioactivity, THQs are important and reliable precursors in quinoline preparation, another group of heterocyclic molecules that has a great number of pharmacological properties [10]. An efficient route in the preparation of THQs is the acid-catalyzed Povarov reaction that is classified as imino Diels-Alder cycloaddition [11,12,13] and permits the condensation of anilines, aldehydes, and electron-rich alkenes using acidic catalysts under mild conditions to achieve the obtainment of new substituted tetrahydroquinolines
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
