Abstract:
Highly active natural pandanus-extracted cellulose-sup ported poly(hydroxamic acid)−Cu(II) complex 4 was synthesized. The
surface of pandanus cellulose was modified through graft copolymerization
using purified methyl acrylate as a monomer. Then, copolymer methyl
acrylate was converted into a bidentate chelating ligand poly(hydroxamic
acid) via a Loosen rearrangement in the presence of an aqueous solution of
hydroxylamine. Finally, copper species were incorporated into poly-
(hydroxamic acid) via the adsorption process. Cu(II) complex 4 was fully
characterized by Fourier transform infrared (FTIR), field emission
scanning electron microscopy (FE-SEM), energy-dispersive X-ray
(EDX), transmission electron microscopy (TEM), inductively coupled
plasma optical emission spectrometry (ICP-OES), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray
photoelectron spectroscopy (XPS) analyses. The cellulose-supported Cu(II) complex 4 was successfully applied (0.005 mol %) to
the Ullmann etherification of aryl, benzyl halides, and phenacyl bromide with a number of aromatic phenols to provide the
corresponding ethers with excellent yield [benzyl halide (70−99%); aryl halide (20−90%)]. Cu(II) complex 4 showed high stability
and was easily recovered from the reaction mixture. It could be reused up to seven times without loss of its original catalytic activity.
Therefore, Cu(II) complex 4 can be commercially utilized for the preparation of various ethers, and this synthetic technique could
be a part in the synthesis of natural products and medicinal compounds.