- 作者: 林月霜 ; 施正雄
- 作者服務機構: 台灣師範大學化學系
- 中文摘要: Various homogeneous and heterogeneous crown ether catalysts were prepared and applied as phase transfer catalysts for some reductions, oxidations and polymerizations. Among various crown ethers, 15-crown-5 seems the best to catalyze the reduction of ketones and aldehydes with sodium borohydride in nonpolar aprotic solvents. A granular entrapped 15-crown-5-polyacrylamide catalysts was also prepared and applied as a heterogeneous catalyst for these reductions which seem to obey pseudo-first-order kinetics with rate constant 10/sup -4/-10/sup -5/s/sup -1/. The steric effects of ketones and the effects of temperature and concentration of crown ethers, sodium borohydride and carbonyl compounds were also investigated. Among various crown ethers, 18-crown-6 is the best to catalyze the oxidation of olefins such as styrene, xylene and stilbene with potassium permanganate. Crown ethers were successfully applied as catalysts for anionic polymerization of p-xylenedibromide with sodium dithionite as an initiator.
- 英文摘要: --
- 中文關鍵字: Crown Ether; Phase Transfer Catalyst; Reduction; Ketone; Oxidation; Olefin; Polymerization; Xylenedibromide
- 英文關鍵字: 冠狀醚;相轉移觸媒;還原;酮;氧化;烯;聚合;二溴二甲苯