应用化学
應用化學
응용화학
CHINESE JOURNAL OF APPLIED CHEMISTRY
2010年
3期
267-271
,共5页
朱晨杰%魏运洋%计磊%张倩
硃晨傑%魏運洋%計磊%張倩
주신걸%위운양%계뢰%장천
聚苯乙烯%功能离子液体%醇%氧化
聚苯乙烯%功能離子液體%醇%氧化
취분을희%공능리자액체%순%양화
polystyrene%task-specific ionic liquid%oxidation%alcohol
将聚苯乙烯树脂(PS)先碘化再乙酰基化,制得了负载型二乙酰氧碘苯(PS-DIB)作为氧化剂.2,2,6,6-四甲基-N-氧自由基哌啶醇(TeMPO)与1,4-二溴丁烷反应生成4-溴丁氧基-2,2,6,6-四甲基-哌啶-1-氧化物,再与N-甲基咪唑发生季铵化反应,生成的溴化季铵盐与四氟硼酸钠进行离子交换制得氟硼酸型2,2,6,6-四甲基-N-氧自由基哌啶负载离子液体(TeMPO-IL).室温下,以离子液体1-甲基-3-丁基咪唑四氟硼酸盐([bmim]BF_4)为溶剂,PS-DIB为氧化剂,TeMPO-IL为催化剂,选择性协同氧化各种醇为相应的醛或酮.在实验条件范围内未检测到羧酸副产物.氧化剂、催化剂和溶剂均可循环使用,在苯甲醇的氧化中,循环使用5次,反应的转化率和收率均保持基本不变.
將聚苯乙烯樹脂(PS)先碘化再乙酰基化,製得瞭負載型二乙酰氧碘苯(PS-DIB)作為氧化劑.2,2,6,6-四甲基-N-氧自由基哌啶醇(TeMPO)與1,4-二溴丁烷反應生成4-溴丁氧基-2,2,6,6-四甲基-哌啶-1-氧化物,再與N-甲基咪唑髮生季銨化反應,生成的溴化季銨鹽與四氟硼痠鈉進行離子交換製得氟硼痠型2,2,6,6-四甲基-N-氧自由基哌啶負載離子液體(TeMPO-IL).室溫下,以離子液體1-甲基-3-丁基咪唑四氟硼痠鹽([bmim]BF_4)為溶劑,PS-DIB為氧化劑,TeMPO-IL為催化劑,選擇性協同氧化各種醇為相應的醛或酮.在實驗條件範圍內未檢測到羧痠副產物.氧化劑、催化劑和溶劑均可循環使用,在苯甲醇的氧化中,循環使用5次,反應的轉化率和收率均保持基本不變.
장취분을희수지(PS)선전화재을선기화,제득료부재형이을선양전분(PS-DIB)작위양화제.2,2,6,6-사갑기-N-양자유기고정순(TeMPO)여1,4-이추정완반응생성4-추정양기-2,2,6,6-사갑기-고정-1-양화물,재여N-갑기미서발생계안화반응,생성적추화계안염여사불붕산납진행리자교환제득불붕산형2,2,6,6-사갑기-N-양자유기고정부재리자액체(TeMPO-IL).실온하,이리자액체1-갑기-3-정기미서사불붕산염([bmim]BF_4)위용제,PS-DIB위양화제,TeMPO-IL위최화제,선택성협동양화각충순위상응적철혹동.재실험조건범위내미검측도최산부산물.양화제、최화제화용제균가순배사용,재분갑순적양화중,순배사용5차,반응적전화솔화수솔균보지기본불변.
A selective and mild PS-DIB(diacetoxyiodo polystyrene)/ionic-liquid immobilized 2,2,6,6-tetramethyl-piperidin-4-ol-N-oxyl(TeMPO) catalytic oxidation procedure of alcohols to the corresponding aldehydes and ketones in ionic liquid [bmim]BF_4 at room temperature was developed. The oxidant PS-DIB was prepared via the iodation and acetylation of polystyrene resin. For the preparation of the ionic-liquid immobilized TeMPO(TeMPO-IL) catalyst,4-(2,2,6,6-Tetramethyl-1-oxyl-4-piperidoxyl)butyl bromide was first synthesized from TeMPO and 1,4-dibromobutane. The TeMPO-IL was then obtained via the quaternization of 1-methyl-1H-imidazole with TeMPO-IL followed by ion exchange with NaBF_4. The PS-DIB/TeMPO-IL catalytic system was applied to the oxidation of a variety of alcohols to their corresponding aldehydes or ketones selectively. No carboxylic acid was detected under the experimental conditions. In the case of the oxidation of benzyl alcohol,the oxidant,catalyst and the solvent can be recovered and reused for 5 times without decreasing the benzyl alcohol conversions and yields.