1452892-29-3Relevant academic research and scientific papers
A3-Coupling catalyzed by robust Au nanoparticles covalently bonded to HS-functionalized cellulose nanocrystalline films
Huang, Jian-Lin,Gray, Derek G.,Li, Chao-Jun
, p. 1388 - 1396 (2013)
We decorated HS-functionalized cellulose nanocrystallite (CNC) films with monodisperse Au nanoparticles (AuNPs) to form a novel nanocomposite catalyst AuNPs@HS-CNC. The uniform, fine AuNPs were made by the reduction of HAuCl4 solution with thiol (HS-) group-functionalized CNC films. The AuNPs@HS-CNC nanocomposites were examined by X-ray photoelectron spectroscopy (XPS), TEM, ATR-IR and solid-state NMR. Characterizations suggested that the size of the AuNPs was about 2-3 nm and they were evenly distributed onto the surface of CNC films. Furthermore, the unique nanocomposite Au@HS-CNC catalyst displayed high catalytic efficiency in promoting three-component coupling of an aldehyde, an alkyne, and an amine (A3-coupling) either in water or without solvent. Most importantly, the catalyst could be used repetitively more than 11 times without significant deactivation. Our strategy also promotes the use of naturally renewable cellulose to prepare reusable nanocomposite catalysts for organic synthesis.
Naked Au nanoparticles monodispersed onto multifunctional cellulose nanocrystal-graphene hybrid sheets: Towards efficient and sustainable heterogeneous catalysts
Wang, Yameng,Zhang, Huinian,Lin, Xiangjun,Chen, Shuai,Jiang, Zhongjie,Wang, Junzhong,Huang, Jianlin,Zhang, Fang,Li, Hexing
, p. 2197 - 2203 (2018/02/07)
A simple, clean, and efficient synthesis method has been developed for deposition of ～3 nm monodisperse "naked" gold nanoparticles (Au NPs) onto cellulose nanocrystal-graphene (CNC-G) hybrid sheets without the use of additional reducing and capping agents. The as-prepared catalysts (Au@CNC-G) were examined using FT-IR spectroscopy, thermogravimetric analysis (TGA), atomic force microscopy, electron microscopy, wide-angle X-ray diffraction, and X-ray photoelectron spectroscopy (XPS). After some optimization, the Au@CNC-G catalyst exhibited robust catalytic activity, impressive stability, and good flexibility for the "one-pot" reaction of an alkyne, an amine, and an aldehyde (A3-coupling) in water. The catalytic activity of the Au@CNC-G catalyst could be attributed to the synergistic effect derived from the coexistence of CNC and graphene. The Au3+ ions could be in situ reduced to create fine Au NPs and simultaneously anchored on the surface of CNC-G hybrid sheets through coordination, leading to the uniform dispersion of the Au NPs. Moreover, the Au@CNC-G catalyst could be conveniently recycled and reused many times, thus lowering the cost and minimizing the environmental pollution caused by organic solvents and heavy metal ions.
