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Abstract We demonstrate a novel approach of utilizing methanol (CH3OH) in a dual role for (1) the methanolysis of polyethylene terephthalate (PET) to form dimethyl terephthalate (DMT) at near‐quantitative yields (~97 %) and (2) serving as an in situ H2source for the catalytic transfer hydrogenolysis (CTH) of DMT to p‐xylene (PX, ~63 % at 240 °C and 16 h) on a reducible ZnZrOxsupported Cu catalyst (i.e., Cu/ZnZrOx). Pre‐ and post‐reaction surface and bulk characterization, along with density functional theory (DFT) computations, explicate the dual role of the metal‐support interface of Cu/ZnZrOxin activating both CH3OH and DMT and facilitating a lower free‐energy pathway for both CH3OH dehydrogenation and DMT hydrogenolysis, compared to Cu supported on a redox‐neutral SiO2support. Loading studies and thermodynamic calculations showed that, under reaction conditions, CH3OH in the gas phase, rather than in the liquid phase, is critical for CTH of DMT. Interestingly, the Cu/ZnZrOxcatalyst was also effective for the methanolysis and hydrogenolysis of C−C bonds (compared to C−O bonds for PET) of waste polycarbonate (PC), largely forming xylenol (~38 %) and methyl isopropyl anisole (~42 %) demonstrating the versatility of this approach toward valorizing a wide range of condensation polymers.
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Facile Synthesis of Triazoles using Electrospray‐Deposited Copper Nanomaterials to Catalyze Azide‐Alkyne Cycloaddition (AAC) Click Reactions
Abstract Electrospray deposition of copper salt‐containing microdroplets onto the liquid surface of an electrically grounded reaction mixture leads to the formation of Cu nanoclusters, which then catalyze the azide‐alkyne cycloaddition (AAC) reaction to form triazoles. This method of in situ nanocatalyst preparation provided 17 times higher catalytic activity compared to that in the conventional catalytic reaction. The gentle landing of the Cu‐containing droplets onto the liquid surface forms a thin film of catalyst which promotes the heterogeneous AAC reaction while showing diffusion‐controlled kinetics. UV‐vis spectral characterization confirms that the catalyst is comprised of Cu nanoclusters. This unique catalytic strategy was validated using several substrates and the corresponding products were confirmed by tandem mass spectrometry (MS/MS) analysis.
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- Award ID(s):
- 1905087
- PAR ID:
- 10372872
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPlusChem
- Volume:
- 87
- Issue:
- 10
- ISSN:
- 2192-6506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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