以超临界二氧化碳(scCO_2)/聚乙二醇(PEG)两相为反应介质,双齿氮配体功能化聚乙二醇稳定的Pd纳米颗粒作为催化剂,进行了醇的需氧氧化反应.系统研究了催化剂制备条件和反应条件对苯甲醇需氧氧化反应的影响.结果表明,以氢气为还原剂制备的Pd纳米粒子的催化活性最高.反应结束后,可以利用seCO_2直接进行原位萃取得到产物,实现了催化剂与产物的有效分离和催化剂的循环使用.反应中没有检测剑钯的流失.催化剂经过5次循环利用后转化率仍可达98%.
The aerobic oxidation of various alcohols to the corresponding aldehydes or ketones was carried out using stabilized palladium nanoparticles in a supercritical carbon dioxide(scCO_2)/poly(ethylene glycol)(PEG-2000)biphasie system.The effects of reaction conditions on catalytie activity were investigated in detail.Among the Pd nano-catalysts reduced with different reductants,Pd nanoparticles obtained by H2 reduction showed the best catalytic performance in the oxidation of benzyl alcoh01.The products Call be easily extracted with scCO_2 in situ from the Pd nano-catalyst immobilized in functionalized poly(ethylene glycol),and therefore the loss of palladium could be eliminated.The conversion reached 98% after the catalyst was reused 5 times.
参考文献
| [1] | Sheldon R A;Arends I W C E;ten Brink G J;Dijksman A .[J].Accounts of Chemical Research,2002,35:774. |
| [2] | Iwasawa T;Tokunaga M;Obora Y;Tsuji Y .[J].Journal of the American Chemical Society,2004,126:6554. |
| [3] | tenBrinkG J;Arends I W C E;Sheldon R A .[J].Science,2000,287:1636. |
| [4] | Hu Y;Yu Y Y;Hou Zh Sh;Li H Zhao X G Feng B .[J].Adv Synth Caml,2008,350:2077. |
| [5] | Karimi B;Zamani A;Abedi S;Clark J H .[J].Green Chemistry,2009,11:109. |
| [6] | Pillai U R;Sahle-Demessie E .[J].Green Chemistry,2004,6:161. |
| [7] | Hou Zh Sh;Theyssen N;Brinkmann A;Klementiev K V Grnnen W Bfihl M Schmidt W Spliethoff B Tesche B Weidenthaler C Leitner W .[J].Journal of Catalysis,2008,258:3 1 5. |
| [8] | 韩布兴.超临界流体科学与技术[M].北京:中国石化出版社,2005 |
| [9] | 胡玉,侯震山.超临界（压缩）二氧化碳介质中的选择氧化[J].化学进展,2007(09):1267-1274. |
| [10] | Wang X G;Kawanami H;Dapurkar S E;Venkataramanan N S Chatterjee M Yokoyama T Ikushima Y .[J].Applied Catalysis A:General,2008,349:86. |
| [11] | Wang Q;Cheng H Y;Liu R X;Hao J M Yu Y C Cai S X Zhao F V .[J].CATALYSIS COMMUNICATIONS,2009,10:592. |
| [12] | Stevens J G;Bourne R A;Poliakoff M .[J].Green Chemistry,2009,11:409. |
| [13] | Chert J;Spear S K;Huddleston J G;Rogers R D .[J].Green Chemistry,2005,7:64. |
| [14] | Heldebrant DJ;Witt HN;Walsh SM;Ellis T;Rauscher J;Jessop PG .Liquid polymers as solvents for catalytic reductions[J].Green chemistry,2006(9):807-815. |
| [15] | 周海峰,范青华,何艳梅,古练权,陈新滋.液态聚乙二醇作为绿色反应介质在有机反应中的应用[J].化学进展,2007(10):1517-1528. |
| [16] | 杨玉川,蒋景阳,王艳华,刘春,金子林.温控PEG两相体系催化三聚丙烯氢甲酰化[J].催化学报,2007(06):557-560. |
| [17] | Guadagno T;Kazarian S G .[J].Journal of Physical Chemistry B,2004,108:13995. |
| [18] | 冯博;胡玉;李欢;侯震山 .[J].有机化学,2007,28:381. |
| [19] | Liu R X;Cheng H Y;Wang Q;Wu C Y Ming J Xi C Y Yu Y C Cai S X Zhao F Y Arai M .[J].Green Chemistry,2008,10:1082. |
| [20] | Heldebrant D J;Jessop P G .[J].Journal of the American Chemical Society,2003,125:5600. |
| [21] | Wang J Q;Cai F;Wang E;He L N .[J].Green Chemistry,2007,9:882. |
| [22] | Hou Zh Sh;Theyssen N;Brinkmann A;Leitner W .[J].Angewandte Chemie International Edition,2005,44:1346. |
| [23] | Hou Zh Sh;Theyssen N;Leitner w .[J].Green Chemistry,2007,9:127. |
| [24] | Mai W;Gao L.[J].Synlett:Accounts and Rapid Communications In Synthetic Organic Chemistry,2006:2553. |
| [25] | Caravati M;Grunwaldt J D;Baiker A .[J].Physical Chemistry Chemical Physics,2005,7:278. |
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