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Verfasst von:Li, Haining [VerfasserIn]   i
 Zhang, Tiantian [VerfasserIn]   i
 Tang, Kai [VerfasserIn]   i
 Li, Binglin [VerfasserIn]   i
 Zhang, Xiaoli [VerfasserIn]   i
 Zhao, Binxia [VerfasserIn]   i
 Wang, Jiao [VerfasserIn]   i
Titel:Preparation of hyperbranched 4-dimethylaminopyridine catalyst for the efficient synthesis of vitamin E succinate
Verf.angabe:Haining Li, Tiantian Zhang, Kai Tang, Binglin Li, Xiaoli Zhang, Binxia Zhao and Jiao Wang
E-Jahr:2023
Jahr:2023-01-16
Umfang:12 S.
Fussnoten:Gesehen am 19.06.2023
Titel Quelle:Enthalten in: Comptes rendus chimie
Ort Quelle:[Paris] : [Académie des sciences, Institut de France], 2002
Jahr Quelle:2023
Band/Heft Quelle:26(2023), G1 vom: Jan., Seite 7-18
ISSN Quelle:1878-1543
Abstract:Sorbitol was employed as the grafting agent to modify nano-silica by the hyperbranched reaction. The obtained carrier was further used to prepare immobilized 4-dimethylaminopyridine (DMAP), which was successfully applied to produce vitamin E succinate. Two crucial steps were systematically investigated during the preparation of hyperbranched loaded DMAP: the epoxy-alcohol addition and N-alkylation reactions. For the epoxy-alcohol addition reaction, the maximum hydroxyl content reached 8.89 mmol/g when the molar ratio of sorbitol to epoxide was 2.5:1, the reaction temperature was 55 °C, the stirring rate was 500 rpm, and the reaction time was 8 h. In the N-alkylation reaction, when the reaction time was 20 h, the reaction temperature was 130 °C, the molar ratio of MAP to KCO was 1:1.5, the KI to MAP molar ratio was 1:1 and the stirring rate was 600 rpm, the highest loading of DMAP reached 5.17 mmol/g. The catalytic performance of the loaded DMAP with different branching levels was evaluated by the acetylation reaction. The highest catalytic activity was observed in the hyperbranched catalyst, which reached 24.97 mmol/hg. Moreover, the stability of the prepared immobilized DMAP was significantly enhanced. After being used for ten batches, 94.9% of the catalytic activity retention rate was obtained.
DOI:doi:10.5802/crchim.219
URL:Bitte beachten Sie: Dies ist ein Bibliographieeintrag. Ein Volltextzugriff für Mitglieder der Universität besteht hier nur, falls für die entsprechende Zeitschrift/den entsprechenden Sammelband ein Abonnement besteht oder es sich um einen OpenAccess-Titel handelt.

Volltext: https://doi.org/10.5802/crchim.219
 Volltext: https://comptes-rendus.academie-sciences.fr/chimie/articles/10.5802/crchim.219/
 DOI: https://doi.org/10.5802/crchim.219
Datenträger:Online-Ressource
Sprache:eng
K10plus-PPN:1850508488
Verknüpfungen:→ Zeitschrift

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