CuNi/Co composites prepared by electroless deposition: structure and catalytic activity for the oxidation of cyclohexene with oxygen

Abstract

CuNi/Co composites with various Cu contents have been prepared by electroless deposition (ELD) of Cu on Co powers and characterized with ICP-OES, N 2 adsorption/desorption, XRD, SEM, TEM and XPS. Their catalytic performance was examined for the allylic oxidation of cyclohexene with oxygen under solventfree conditions. The phase structure of the Cu deposit in the composites is transformed from an amorphous phase to a crystalline phase with the increase in Cu content. The composition and microstructure of the Cu deposit in the composite significantly affect its catalytic activity for the oxidation of cyclohexene. CuNi-ELD/Co-5 composite with 6.0 wt% Cu content and amorphous Cu deposit showed the highest catalytic performance with a 46.3% conversion of cyclohexene and 88.1% total selectivity to 2-cyclohexene-1-ol (Cy-ol), 2-cyclohexene-1-one (Cy-one), 2-cyclohexene-1-hydroperoxide (Cy-HP) and cyclohexene oxide (Cy-oxide).

Selective Catalytic Oxidation of Cyclohexene with Molecular Oxygen: Radical Versus Nonradical Pathways

“…The allylic oxidation of alkenes is an important chemical reaction. It allows us to keep the double bond and at the same time create a new alcohol or carbonyl function . As such, it is useful across the board, from bulk chemicals and agrochemicals all the way to fine chemicals and fragrances .…”

Fe3O4 magnetic nanoparticles (MNPs) as an efficient catalyst for selective oxidation of benzylic and allylic C–H bonds to carbonyl compounds with tert-butyl hydroperoxide

“…22 Benzylic CH 2 groups have high reactivity toward oxidizing agents, generating aryl ketones with high efficiency. Several metallic based allylic oxidation were also documented such as PdO/SBA-15, 23 Au catalysts, 24 sulfonamide-substituted iron phthalocyanine, 25 CuNi/ Co composites, 26 Ru/Ti-PILC, 27 manganese porphyrin, 28 n-Bu 4 NI/ TBHP. 29 Since the metal residues are environmentally undesirable and oen provide problems during reaction and workup, development of oxidizing methods, which requires only a catalytic amount of metal reagent in combination with appropriate stoichiometric oxidant, is highly desirable and it is one of the major goals of green chemistry.…”

Heteropolyacid-Based Poly(ionic liquid)s for the Selective Oxidation of Cyclohexene to 2-Cyclohexene-1-one

“…17−22 For instance, Dou et al 23 reported a porous nano-Au (Ag) catalyst for the selective oxidation of cyclohexene with molecular oxygen as oxidant and obtained a cyclohexene conversion of 12% with a selectivity to 2cyclohexene-1-one of 30%. Hao et al 24 synthesized CuNi/ Co composites and used them to catalyze the oxidation of cyclohexene in the presence of molecular oxygen. The conversion of cyclohexene and the selectivity to 2-cyclohexene-1-one were 46.3 and 28.1%, respectively.…”

“…In addition, the conventional catalysts applied for the process are homogeneous metal complexes, which have some inherent drawbacks, such as the high cost of ligands and difficulty in separation and reuse. − In view of the low cost, availability, and eco-friendliness, the selective oxidation of cyclohexene over heterogeneous catalysts with molecular oxygen as an environmentally benign oxidant has gained great interest in recent years. − For instance, Dou et al reported a porous nano-Au (Ag) catalyst for the selective oxidation of cyclohexene with molecular oxygen as oxidant and obtained a cyclohexene conversion of 12% with a selectivity to 2-cyclohexene-1-one of 30%. Hao et al synthesized CuNi/Co composites and used them to catalyze the oxidation of cyclohexene in the presence of molecular oxygen. The conversion of cyclohexene and the selectivity to 2-cyclohexene-1-one were 46.3 and 28.1%, respectively.…”