دورية أكاديمية
Pd-PEPPSI catalysts bearing N-heterocyclic carbene ligands derived from caffeine and theophylline for Mizoroki–Heck and C(sp2)–H arylation reactions
| العنوان: | Pd-PEPPSI catalysts bearing N-heterocyclic carbene ligands derived from caffeine and theophylline for Mizoroki–Heck and C(sp2)–H arylation reactions |
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| المؤلفون: | Mazars, François, Etse, Koffi Senam, Zaragoza, Guillermo, Delaude, Lionel |
| المصدر: | Journal of Organometallic Chemistry, 1003, 122928 (2023-12-15) |
| بيانات النشر: | Elsevier B.V., 2023. |
| سنة النشر: | 2023 |
| مصطلحات موضوعية: | Alkaloids, Carbene ligands, Cross-coupling, Green chemistry, Hirshfeld surface, Aryl bromides, Arylation reactions, Catalyst precursors, Cross-couplings, Electron-withdrawing substituents, Green-chemistry, Hirshfeld surfaces, N-heterocyclic carbene ligands, ]+ catalyst, Biochemistry, Physical and Theoretical Chemistry, Organic Chemistry, Inorganic Chemistry, Materials Chemistry, Physical, chemical, mathematical & earth Sciences, Chemistry, Physique, chimie, mathématiques & sciences de la terre, Chimie |
| الوصف: | The activity of three Pd-PEPPSI catalyst precursors bearing N-heterocyclic carbene (NHC) ligands derived from caffeine and theophylline was tested in Mizoroki–Heck reactions between styrene and five different aryl bromides bearing electron-donating or withdrawing substituents. Moderate to excellent conversions (44–98%) were achieved within 3 h at 100 °C with K2CO3 as the base and 1 mol% of catalyst in a green water/isopropanol mixture under a normal atmosphere. Electron-withdrawing groups favored the reaction and led to the highest yields of stilbene products (up to 85% after chromatographic purification). The activity of the three [PdX2(NHC)(Py)] complexes (X = Cl, I) was also probed in the C(sp2)–H arylation of two heterocyclic substrates using the same set of five representative aryl bromides. Experimental conditions were further optimized on a model reaction (1 mol% of catalyst in DMA at 120 °C for 4 h with KOAc as the base). Gratifyingly, 1-methyl-2-pyrrolecarboxaldehyde afforded high conversions (59–99%) and yields of isolated products (49–85%), with the best results obtained again under the influence of electron-withdrawing substituents. When a more challenging substrate, viz., 3,5-dimethylisoxazole was used, modest to satisfactory conversions (41–80 %) and yields (30–69%) could still be reached with the best catalyst for each reaction. The structural properties of the complexes under investigation were compared using X-ray crystallography and Hirshfeld surface analysis. |
| نوع الوثيقة: | journal article http://purl.org/coar/resource_type/c_6501 article peer reviewed |
| اللغة: | English |
| Relation: | https://api.elsevier.com/content/article/PII:S0022328X23003169?httpAccept=text/xml; urn:issn:0022-328X |
| DOI: | 10.1016/j.jorganchem.2023.122928 |
| URL الوصول: | https://orbi.uliege.be/handle/2268/309258 |
| حقوق: | restricted access http://purl.org/coar/access_right/c_16ec info:eu-repo/semantics/restrictedAccess |
| رقم الأكسشن: | edsorb.309258 |
| قاعدة البيانات: | ORBi |
| DOI: | 10.1016/j.jorganchem.2023.122928 |
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