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Preparation of Modified Chitosan Microsphere-Supported Copper Catalysts for the Borylation of ?,?-Unsaturated Compounds.

ABSTRACT: Chitosan microspheres modified by 2-pyridinecarboxaldehyde were prepared and used in the construction of a heterogeneous catalyst loaded with nano-Cu prepared by a reduction reaction. The chemical structure of the catalyst was investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). Under mild conditions, such as no ligand at room temperature, the catalyst was successfully applied to catalyze the borylation of ?,?-unsaturated receptors in a water-methanol medium, yielding 17%-100% of the corresponding ?-hydroxy product. Even after repeated use five times, the catalyst still exhibited excellent catalytic activity.

SUBMITTER: Wang W

PROVIDER: S-EPMC6788198 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Preparation of Modified Chitosan Microsphere-Supported Copper Catalysts for the Borylation of α,β-Unsaturated Compounds.

Wang Wei W Xiao Zufeng Z Huang Chaofan C Zheng Kewang K Luo Yin Y Dong Yumin Y Shen Zitong Z Li Wei W Qin Caiqin C

Polymers 20190828 9

Chitosan microspheres modified by 2-pyridinecarboxaldehyde were prepared and used in the construction of a heterogeneous catalyst loaded with nano-Cu prepared by a reduction reaction. The chemical structure of the catalyst was investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). Under mild conditions, such as no ligand at room temperature, the catalyst was successfu ...[more]

PMID: 31466406

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