Magnetic nanoparticles supported oxime palladacycle as a highly efficient and separable catalyst for room temperature Suzuki–Miyaura coupling reaction in aqueous media

Abstract

A novel magnetic nanoparticle-supported oxime palladacycle catalyst was successfully prepared and characterized. The magnetically recoverable catalyst was evaluated in room temperature Suzuki-Miyaura cross-coupling reaction of aryl iodides and bromides in aqueous media. The catalyst was shown to be highly active under phosphine-free and low Pd loading (0.3 mol%) conditions. The catalyst could be easily separated from the reaction mixture using an external magnet and reused for six consecutive runs without a significant loss of activity.

Oxime‐Derived Palladacycles: Applications in Catalysis

“…In the search for a palladacycle that can be easily removed from the reaction medium, very recently a catalyst derived from 4‐aminoacetophenone has been supported on magnetite nanoparticles coated with a thin layer of silica by using a sol–gel process to give core–shell NPs. This supported palladacycle 16 (Figure ) showed high efficiency in aqueous EtOH (1:1) at room temperature by using t BuOK as base and 0.3 mol % Pd loading for the cross‐coupling of activated and deactivated aryl iodides and bromides with PhB(OH) 2 . Only activated aryl chlorides afforded moderate reactivity at 60 °C.…”

Recent Advances in the Palladium Catalyzed Suzuki–Miyaura Cross-Coupling Reaction in Water

“…The catalyst Heck and SMC in water, and could be conveniently separated and recovered by applying a permanent magnet (Scheme 40). The supported catalyst could be used consecutively for six runs without significant loss of catalytic activity.A novel magnetic nanoparticle-supported oxime palladacycle catalyst 59 was prepared and characterized by Gholinejad [76]. The magnetically recoverable catalyst was employed at room temperature for the SMC of aryl iodides and bromides in aqueous media.…”

ChemInform Abstract: Oxime‐Derived Palladacycles: Applications in Catalysis

“…In the searchf or ap alladacycle that can be easily removed from the reaction medium, very recently ac atalyst derived from 4-aminoacetophenone has been supported on magnetite nanoparticles coated with at hin layer of silica by using as olgel process to give core-shell NPs. This supported palladacycle 16 [88] (Figure 3) showedh igh efficiency in aqueous EtOH (1:1) at room temperature by using tBuOK as base and 0.3 mol %P d loading for the cross-coupling of activated and deactivated aryl iodides and bromides with PhB(OH) 2 .O nly activated aryl chlorides afforded moderate reactivity at 60 8C. Comparison studies on the catalytic activity of 16 with other supported oxime-derived complexes such as 4 and 14 for the cross-coupling of 4-bromoanisole with phenylboronic acid indicated ah igher efficiency for 16.I nt he case of the cross-coupling of 4-bromoacetophenone and phenylboronic acid, complex 16 showedb etter efficiencyt han the silica gel supported complex 7a.W ith respect to recycling experimentso f16,f or the reactiono f4 -bromoanisole with phenylboronic acid at room temperature, the efficiency couldb em aintained for at least six cycles, the complex could be recovered by means of an external magnet although 1.6 %P dl eaching was detected in the solution.…”