Studies on Pd/NiFe₂O₄ catalyzed ligand-free Suzuki reaction in aqueous phase: synthesis of biaryls, terphenyls and polyaryls

Abstract

SummaryPalladium supported on nickel ferrite (Pd/NiF2O4) was found to be a highly active catalyst for the Suzuki coupling reaction between various aryl halides and arylboronic acids. The reaction gave excellent yields (70–98%) under ligand free conditions in a 1:1 DMF/H2O solvent mixture, in short reaction times (10–60 min). The catalyst could be recovered easily by applying an external magnetic field. The polyaryls were similarly synthesized.

A review of the contribution of cowpea leaves to food and nutrition security in East Africa

“…However, cowpea still remains a minor crop across Europe with most of the consumed vegetable being imported. Asia has for a long period of time ranked second to Africa in terms of production of cowpeas (Nedumaran et al, 2015). Asia has for a long period of time ranked second to Africa in terms of production of cowpeas (Nedumaran et al, 2015).…”

“…Of the developed countries, only USA is a substantial producer and exporter of cowpeas (Directorate Plant Production, 2014). Asia has for a long period of time ranked second to Africa in terms of production of cowpeas (Nedumaran et al, 2015).…”

Synthesis, Characterization and Catalytic Applications of 2,2-Dimethylpropane-1,3-Diaminopalladium(II) Complex in Mizoroki-Heck Reaction

“…The selected bond lengths and angles are listed in Table- Catalytic testing of homogeneous Mizoroki-Heck crosscoupling reaction: After confirming the exact structure of the synthesized complex PdL SB , the catalytic activity of organic reaction was then tested by using 4-bromoacetophenone and methyl acrylate in the presence of sodium acetate as base and solvent at optimum reaction temperature (120 ºC) for 12 h. The reaction was carried out in a Radleys 12-placed carousel reactor vessel whilst continuously flushed with nitrogen gas. However, the temperature must be carefully controlled to avoid the palladium black formation that will inhibit the catalytic cycle if the temperature was too high [16]. The catalyst loading was kept to 1.0 mmol % so as to produce an expected turnover number (TON) of 100 if 100 % conversion was achieved.…”

ChemInform Abstract: Recent Applications of Magnetically Recoverable Nanocatalysts in C—C and C—X Coupling Reactions

“…[20][21][22][23][24] The use of nanoferrites instead of Fe 3 O 4 nanoparticles is an alternative route that can be used to stabilize catalytically active palladium on magnetic materials directly.I nt his regard, Waghmode and co-workersh ave developed ap rotocol for the immobilization of Pd nanoparticles on NiFe 2 O 4 as am agnetically separable catalystf or the Suzuki reaction. [25] . Aryl iodides and bromides give the products in satisfactory yields in 5-150 min at 90 8C, but the coupling products are formed in yields of only 6-42 %i fl ess reactive aryl chlorides are used, even after 24 ha t1 05 8C.…”

“…Immobilization of Pd nanoparticles in the channels of superparamagnetic mesoporous NiFe 2 O 4 as am agnetic catalystf or the Suzuki reactionh as been reported by Shi et al [26] At emplate-free coprecipitation methodi se mployed for the synthesis of mesoporousN iFe 2 O 4 in the presence of oxalic acid, and deposition of Pd 0 is achieved in as imilarw ay,a sd escribed by Waghmode. [25] Catalyst MNP-5 can be used at al oading as low as 0.08 mol %f or the Suzukic oupling of aryl iodides and bromides at 80 8Ct og ive biaryls in satisfactory yields within 1-12 h, but for the coupling of chlorobenzene with phenylboronic acid, the coupled product is formed in only 19 %y ield, even after 24 h( Scheme 5). Moreover,t he authors point out that by increasing the basicity of the mesoporousN iFe 2 O 4 support,t he catalytic activity of the system can be considerably improved.…”