Autor: Wen Ying Xu, Tadahiro Wakui, Johannes Smid, Chi‐Sung Chen
Rok vydání: 1986
Předmět:
Zdroj: Die Makromolekulare Chemie. 187:533-545
ISSN: 0025-116X
DOI: 10.1002/macp.1986.021870306
Popis: Oligo(oxyethylene)s immobilized as pendant groups on a polymethacrylate-based resin were used as phase transfer catalysts in the reaction of solid alkali phenoxides with octyl halides in toluene and in the synthesis of benzyl acetate from benzyl bromide and solid alkali acetates in chloroform. The resins are cross-linked homopolymers or copolymers of methyl ethers of oligo(ethylene glycol) methacrylates of the general formula H2CC(CH3)COO(CH2CH2O)n CH3 with n = 4 (MG4), 8 (MG8) or 22 (MG22), the comonomers being styrene, methyl methacrylate (MMA), acrylonitrile or 4-vinylpyridine. The conversion of the organic halides into the respective products were found to be all pseudo first order reactions and the observed rate constants are proportional to the amount of added catalyst and decrease with increasing crosslinking density of the catalyst. Catalysts with longer oligo(oxyethylene) chains have considerably higher activity. Incorporation of more than 50 mol-% MMA comonomer decreases the catalytic activity at least for the benzyl bromide reaction, but the structure of the comonomer has no significant effect. The catalysts are easily synthesized in large quantities from commercially available monomers.
Databáze: OpenAIRE
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