Palladium/Magnesium‐Lanthanum Mixed Oxide Catalyst in the Heck Reaction

Abstract

A new, reusable palladium/magnesium-lanthanum mixed oxide catalyst has been found to exhibit unprecedented high catalytic activity and selectivity for the heterogeneous Heck cross-coupling reaction of aryl halides with alkenes. The nature of the aryl halides has a determinate effect on the reaction yield. The corresponding reactions of a wide range of activated and non-activated aryl bromides and chlorides furnished the arylated product with high E/Z isomer ratios even already at 80 8C. The stereoselectivity depended on the nature of the olefins.

Efficient Heterogeneously Palladium‐Catalysed Heck Arylation of Acrolein Diethyl Acetal. Selective Synthesis of Cinnamaldehydes or 3‐Arylpropionic Esters

“…To overcome these difficulties, the use of heterogeneous palladium catalysts remains a method of choice. Several supports were used to immobilise palladium complexes or to support palladium particles for the Heck reaction: ligand-protected palladium nanoparticles, [43][44][45][46][47][48][49] palladium on active carbon [50][51][52][53] or carbon nanotubes, [54] palladium on metal oxides [27,[55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74] or palladium on functional polymers. [75][76][77][78][79] Among them the zeolites showed exceptional activity and stability.…”

Folyadékfázisú, heterogén katalitikus reakciók alkalmazása szerves kémiai szintézisekben

“…Megállapítottuk, hogy a magnézium-lantán (3:1) vegyes oxid hordozóra felvitt palládium(0) alkalmas heterogén katalizátor a Heck-, Sonogashira-és Suzuki-kapcsolás megvalósítására (12. ábra). [23][24][25] A reakciókban nem volt szükség ligandum hozzáadására. A Heck-reakcióban az E-konfigurációjú olefin keletkezett kizárólagosan vagy nagy feleslegben, a szubsztrátumtól függõen.…”

Nanocrystalline Magnesium Oxide‐Stabilized Palladium(0): An Efficient and Reusable Catalyst for Selective Reduction of Nitro Compounds

“…[14] Other catalysts were synthesized based on the literature reports. [17,18] Preparation of Nanocrystalline MgO Stabilized Palladium Catalyst …”