Abstract
Arylidene-Δ2-pyrrolin-4-ones undergo organocatalyzed annulation with malononitrile, furnishing dihydropyrano[3,2-b]pyrroles (18 examples, 0–77% ee in dichloromethane, 11–44% ee in methanol). The products could be enantiomerically enriched by trituration (11 examples, 95–99% ee). Enantioselectivity was dependent on the nature of the substrate and the conformation of the catalyst, which in turn was solvent-controlled. The reaction mechanism, which included two pseudo-enantiomeric organocatalyst conformations, was investigated by experimental and quantum chemical methods. The reaction mechanism consists of Michael addition reaction step followed by 6-exo-dig annulation, which was found to be the rate determining step. Additionally, it was identified that the preferred reaction pathway follows the model originally proposed by Pápai et al.
Keywords
organokataliza;asimetrična sinteza;enantioselektivnost;učinki topil;piroloni;psevdo-enantiomerne konformacije katalizatorja;organocatalysis;asymmetric synthesis;enantioselectivity;solvent effects;pyrrolone;pseudo-enantiomeric catalyst conformations;
Data
Language: |
English |
Year of publishing: |
2022 |
Typology: |
1.01 - Original Scientific Article |
Organization: |
UL FKKT - Faculty of Chemistry and Chemical Technology |
UDC: |
547.74:544.47 |
COBISS: |
97278211
|
ISSN: |
1615-4150 |
Views: |
204 |
Downloads: |
15 |
Average score: |
0 (0 votes) |
Metadata: |
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Other data
Secondary language: |
Slovenian |
Secondary keywords: |
organokataliza;asimetrična sinteza;enantioselektivnost;učinki topil;piroloni;psevdo-enantiomerne konformacije katalizatorja; |
Type (COBISS): |
Article |
Embargo end date (OpenAIRE): |
2023-01-14 |
Pages: |
str. 980-993 |
Volume: |
ǂVol. ǂ364 |
Issue: |
ǂiss. ǂ5 |
Chronology: |
1 Mar. 2022 |
DOI: |
10.1002/adsc.202101369 |
ID: |
14536735 |