A Cobalt(II)‐containing Metal‐Organic Framework Showing Catalytic Activity in Oxidation Reactions

Abstract

A metal‐organic framework (MOF) containing redox active CoII atoms, [CoII(BPB)]·3DMF (1), has been prepared from the solvothermal reaction of CoII nitrate and 1,4‐bis(4′‐pyrazolyl)benzene (H2‐BPB) in dimethylformamide (DMF). Compound 1 constitutes a porous coordination framework that is built up by interconnecting 1D CoII polymer chains with (BPB)2− ligands. The thermal stability of 1 was investigated by thermogravimetric (TG) analysis and variable‐temperature X‐ray powder diffraction (VTXRPD), which indicate that the framework of 1 is stable upon removal of solvent molecules. The argon adsorption isotherm of 1 at 77 K indicates a porous structure with a BET surface area of 1207 m2/g. As a test reaction for catalytic activity of 1, the oxidation of cyclohexene was examined employing tert‐butyl hydroperoxide as oxidant. The maximum substrate conversion achieved after 12 h was 62 % with an estimated turn‐over number (TON) of 44 based on the number of converted substrate molecules (cyclohexene) per CoII atom.

Metal-Organic Frameworks as Selective or Chiral Oxidation Catalysts

“…As shown in Figure 3, two Co-MOF structures, [Co 3 (μ 2 -OH) 4 (I) 2 ] and MFU-1 are given as examples. MFU-1 is designed by the group of Volkmer, they applied TBHP as an oxidant for the evaluation of their CoMOFs (entries 5-6 Table 4) 11,90 . In both studies very high selectivities were obtained toward the allylic substitution product, tert-butyl-2-cyclohexenyl-1-peroxide (83%) (Scheme 10, product 4), suggesting a mechanism in which peroxy radicals are created by a reductive cleavage of tert-butyl hydroperoxo ligands coordinating to Co(III) metal centers.…”

Aerobic Epoxidation of Olefins Catalyzed by the Cobalt‐Based Metal–Organic Framework STA‐12(Co)

“…Co-based MOFs have been used previously for the oxidation of cyclohexene with tBuOOH, resulting mainly in allylic oxidation products. [40,41] In this study, the epoxidation of styrene and stilbene by molecular oxygen is investigated by using DMF as the solvent and the MOF catalyst STA-12(Co). The MOF structure has been resolved by Rietveld refinement and it features an analogous structure to STA-12(Ni) [42] and is therefore a high-metal-containing alternative to the frequently used zeolites.…”

Metal–organic framework MIL-53(Al)-supported copper catalyst for CO catalytic oxidation reaction

“…Metal-organic frameworks (MOFs) have attracted much attention because of their varied nano structures which can be controlled by a self-assembly process [1][2][3][4][5]. With high pore volume, large surface area and geometrical control, MOFs have more extensive applications than other porous materials, such as for adsorption separation, catalysts, optical and battery materials [6][7][8][9][10].…”