Pd immobilized on EDTA-modified cellulose: synthesis, characterization, and catalytic application in inter- and intramolecular Heck reactions and Larock reactions

• Published in: Research on chemical intermediates Vol. 48; no. 8; pp. 3475 - 3496
• Main Authors: Xu, Zhian, Xu, Jinxi, Zhou, Yuping, Huang, Yuling, Li, Yiqun
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2022; Springer Nature; Springer Nature B.V
• Subjects: Alkenes; Carbon; Catalysis; Catalysts; Catalytic activity; Cellulose; Cellulose esters; Chemical reactions; Chemical synthesis; Chemistry; Chemistry and Materials Science; Chemistry, Multidisciplinary; Emission analysis; Esterification; Ethylenediaminetetraacetic acids; Indoles; Inductively coupled plasma; Inorganic Chemistry; Metathesis; Nanoparticles; Palladium; Physical Chemistry; Physical Sciences; Science & Technology; X ray photoelectron spectroscopy; Larock reactions; EDTA; Heck reactions; Cellulose; Pd catalyst; PALLADIUM; SUZUKI-MIYAURA; INDOLES; NANOPARTICLES; SONOGASHIRA; KINETICS; MIZOROKI; HETEROANNULATION
• ISSN: 0922-6168; 1568-5675
• DOI: 10.1007/s11164-022-04766-x

Pd immobilized on EDTA-modified cellulose (Pd@Cell-EDTA) was successfully prepared through sequential procedure of esterification of cellulose with ethylenediaminetetraacetic acid (EDTA) dianhydride and metathesis with PdCl 2 . The as-synthesized Pd@Cell-EDTA was well characterized by ICP-AES, FTIR, SEM, EDX, elemental mapping, TEM, and XPS tools. TEM revealed that spherical Pd nanoparticles were homogeneously dispersed on the surface of Cell-EDTA with a narrow size of about 5 nm and the Pd content in fresh Pd@Cell-EDTA catalyst was determined to be 0.10 mmol/g by ICP-AES. Due to the regulation of multidentate sites of EDTA, the immobilized Pd exhibited high catalytic activity in the inter- and intramolecular Heck reactions and heteroannulation Larock reactions to afford the desired products in excellent yields (66–97%). The catalyst recycling experiments for the model Heck reaction showed that the catalyst can be reused at least four consecutive runs with a slight drop in its catalytic activity. This catalyst proved its practical applications in the form of carbon–carbon and carbon–heteroatom bond for synthesis of diverse arylated alkenes and indoles. Graphical abstract