2026-04-17T06:13:03Zhttps://recercat.cat/oai/request
oai:recercat.cat:2072/4505362024-12-20T20:36:31Zcom_2072_300912com_2072_4427col_2072_301309
RECERCAT author Núñez-Rico, José Luis author Rellán-Piñeiro, Marcos author Puértolas, Begoña author Vidal-Ferran, Anton author López, Núria author Pérez-Ramírez, Javier author Wershofen, Stefan 2021-08-23T09:41:05Z2024-04-23T10:19:46Z 2021-08-23T09:41:05Z2024-04-23T10:19:46Z 2020-07-17 http://hdl.handle.net/2072/450536 https://doi.org/10.1002/chem.202003201 The methoxycarbonylation of anilines stands as an attractive method for the phosgene-free production of carbamates. Despite the high yields obtained for ceria catalysts, the reduction of the amount of side products and the prevention of catalyst deactivation still represent major hurdles in this chemistry. One advantage of ceria is the possibility of tuning its reactivity by doping its lattice with other metals. In the present work, a series of doped ceria-based materials, prepared by substitution with metals, are evaluated in the methoxycarbonylation of 2,4-diaminotoluene with dimethyl carbonate. Among all catalysts, containing Eu, Hf, La, Pr, Sm, Tb, Y or Zr, ceria promoted with 2 mol % Zr exhibited 96 % selectivity towards the desired carbamates, improving the pure CeO2 catalyst. Density functional theory demonstrates that two descriptors are needed: 1) a geometric factor that governs the reduction of energy barriers for carbamate formation through ureas; 2) catalyst basicity as N−H bonds need to be activated. Assessment in subsequent reaction cycles revealed that the CeO2–ZrO2 catalyst is more stable than bulk CeO2, along with the reduction of fouling processes. eng L'accés als continguts d'aquest document queda condicionat a l'acceptació de les condicions d'ús establertes per la següent llicència Creative Commons:http://creativecommons.org/licenses/by-nc-nd/4.0/ Enhanced Performance of Zirconium-Doped Ceria Catalysts for the Methoxycarbonylation of Anilines info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion URL https://recercat.cat/bitstream/2072/450536/4/nunez-rico_chem_eur_j_2020.pdf File MD5 0e68a52477458269d27b5df34671a6d1 2018191 application/pdf nunez-rico_chem_eur_j_2020.pdf URL https://recercat.cat/bitstream/2072/450536/5/nunez-rico_chem_eur_j_2020.pdf.txt File MD5 efe417063e72c1c54d99853f1014e1f0 44482 text/plain nunez-rico_chem_eur_j_2020.pdf.txt