Heterogeneous Mn@CeO₂ Catalyst for α-Alkylation of Ketones with Alcohols via Hydrogen-Borrowing Strategy

ACS Omega, Год журнала: 2025, Номер 10(9), С. 9649 - 9660

Опубликована: Фев. 24, 2025

Construction of a C-C bond via alkylation ketones with alcohol as the alkylating source by employing hydrogen-borrowing strategy is attracting significant attention and highly appealing due to its simplicity, cost-effectiveness, environmental benefits, fact that water only byproduct. The development heterogeneous catalysts based on nonprecious base metals progressing rapidly. Our newly disclosed manganese-doped cerium oxide nanocomposite (10 wt % Mn@CeO2) stands out cost-efficient air-stable catalyst, synthesized through straightforward coprecipitation method employed for α-alkylation primary alcohols strategy. X-ray diffraction (XRD) analysis confirms high crystallinity CeO2, while field emission scanning electron microscopy (FE-SEM) high-resolution transmission (HR-TEM) images reveal MnO2 nanoparticles, measuring 19 nm in size, uniformly decorated rod-shaped CeO2 which have size 33 nm. photoelectron spectroscopy (XPS) uncovers presence Mn4+ species embedded nanorods. Electron paramagnetic resonance (EPR) further indicates surface defects contribute impressive catalytic yield, ranges from 70 98% α-alkylated ketones. Thermogravimetric (TGA) demonstrates remarkable thermal stability maintaining up 800 °C. Additionally, inductively coupled plasma mass spectrometry (ICP-MS) no leaching Mn ions, emphasizing heterogeneity catalyst. Remarkably, 10 Mn@CeO2 recycled six cycles loss activity. This study underscores synergistic effect between metal redox pair key exceptional activity reactions, making promising catalyst sustainable efficient formation.

Язык: Английский

Highly efficient palladium‐catalyzed hydroesterification of functionalized alkenes

Applied Organometallic Chemistry, Год журнала: 2024, Номер 38(8)

Опубликована: Май 29, 2024

Herein, we introduce a catalytic system consisting of Pd (OAc) 2 /Xantphos/Al (OTf) 3 , which exhibits excellent reactivity in catalyzing the hydroesterification wide range substrates, including electron‐deficient unsaturated acids/esters, aliphatic alkenes, functionalized styrenes, and phenylacetylenes. The featured high selectivity, low catalyst loading, substrate scope, CO pressure. Importantly, it eliminated need for corrosive strong Brønsted acid additives, yielding alkyl‐ or aryl‐substituted dicarboxylic esters monocarboxylic ester derivatives that hold significant industrial pharmaceutical value. Mechanistic studies indicate reaction proceeds via palladium hydride pathway.

Язык: Английский