Novel macroporous palladium cation crosslinked chitosan membranes for heterogeneous catalysis application.
A novel palladium supported on chitosan porous membrane heterogeneous catalyst has been prepared by freeze-drying of Pd(2+)-crosslinked chitosan gel solution. The prepared membrane catalyst has three-dimensional porous structure (porosity: >70%). The crosslinking effects of Pd(2+) to chitosan were good for the improvement of the mechanical properties and thermal stabilities. Pd(2+) cations have been shown not only as the crosslinker, but also as the catalytic active sites. The reductive palladium species of the recycled membrane catalysts was found in the nanometer scale (20-40nm). Excellent cross-coupling yields were achieved using as low as 0.12mol% palladium catalyst loading for the Heck-type reaction of aromatic halides with acrylates. The catalyst could be recycled six times without obvious decreased conversion.
Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
Minfeng
M
Zeng
Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
Xia
X
Yuan
Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China.
Zhen
Z
Yang
Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process, Shaoxing University, Shaoxing 312000, China. Electronic address: qichenze@usx.edu.cn.
Chenze
C
Qi
D000179:Acrylates / Q000737:chemistry; D002384:Catalysis; D002412:Cations; D048271:Chitosan / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D005612:Freeze Drying; D005782:Gels / Q000737:chemistry; D007462:Iodobenzenes / Q000737:chemistry; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D010165:Palladium / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D016062:Porosity; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014961:X-Ray Diffraction
D000179:Acrylates; D002412:Cations; D003432:Cross-Linking Reagents; D005782:Gels; D007462:Iodobenzenes; D008567:Membranes, Artificial; D010165:Palladium; C032490:n-butyl acrylate; D048271:Chitosan; C031905:iodobenzene; D004121:Dimethyl Sulfoxide
Chitosan; Heterogeneous catalysis; Porous membranes