Expanding applications of copper-based metal-organic frameworks in catalysis: Oxidative C-O coupling by direct C-H activation of ethers over Cu2(BPDC)2(BPY) as an efficient heterogeneous catalyst

A crystalline porous metal-organic framework Cu-2(BPDC)(2)(BPY) was synthesized and characterized by Xray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectra, atomic absorption spectrophotometry (AAS), hydrogen temperature-programmed reduction (H-2-TPR), and nitrogen physisorption measurements. The Cu-MOF could be used as an efficient heterogeneous catalyst for the copper-catalyzed cross-dehydrogenative coupling reaction of ethers with 2-carbonyl-substituted phenols. The Cu-2(BPDC)(2)(BPY) exhibited significantly higher catalytic activity than that of other Cu-MOFs such as Cu-3(BTC)(2), Cu(BDC), and Cu(BPDC). The Cu-MOF also offered advantages over several copper salts such as CuCl2, CuCl, , Cu(NO3)(2), and Cu(OAc)(2) in terms of the catalytic activity as well as the catalyst reusability. To the best of our knowledge, the cross-dehydrogenative coupling reaction of ethers with 2-carbonyl-substituted phenols via C-H activation under oxidative conditions using a heterogeneous catalyst was not previously mentioned in the literature. (C) 2013 Elsevier Inc. All rights reserved.