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采用有机金属Pd_2(dba) _3(dba为二亚苄基丙酮)还原分解法制得均匀分布的Pd纳米颗粒(粒径为3~6nm)混合液,并用活性炭直接吸附得到了组合型Pd/C纳米催化剂.采用透射电子显微镜、X射线光电子能谱和X射线衍射等手段测定了催化剂表面Pd颗粒大小分布、晶型和化学态等.将该催化剂用于Suzuki碳-碳偶联反应,其催化活性比浸渍法制备的Pd/C催化剂高2倍以上.以溴代芳烃为底物时,在80℃下0.5h后偶联产物收率可达98%以上.以邻氯硝基苯为底物时,在110°C下1 h后偶联产物收率可达64%:延长反应时间,产物收率可达90%以上.

The Pd nanoparticles with diameters of 3-6 nm were obtained by the decomposition of Pd_2(dba) _3 (dba = dibenzalacetone). They were captured by activated carbon directly to prepare the assembled Pd/C catalyst. Transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were used to characterize the size, distribution, and electronic state of Pd nanoparticles. This assembled catalyst showed extraordinary properties in Suzuki coupling reaction, which was over twice than the Pd/C catalyst prepared by the impregna-tion method. Under the conditions of 80 ℃ and 0.5 h, the catalyst can catalyze Suzuki reactions of aryl bromide with a coupling product yield of 98%. The assembled Pd/C catalyst can also catalyze the reaction of o-chloronitrobenzene with a yield of 64% in 1 h when the reac-tion temperature was 110 ℃, and the yield can be higher than 90% with extending the reaction time.

参考文献

[1] Beletskaya 1 P;Cheprakov A V .[J].Chemical Reviews,2000,100:3009.
[2] Biffis A;Zecca M;Basato M .[J].Journal of Mol Catal A,2001,173:249.
[3] Astruc D .Palladium nanoparticles as efficient green homogeneous and heterogeneous carbon-carbon coupling precatalysts: A unifying view[J].Inorganic Chemistry: A Research Journal that Includes Bioinorganic, Catalytic, Organometallic, Solid-State, and Synthetic Chemistry and Reaction Dynamics,2007(6):1884-1894.
[4] Kuuloja N;Kylmala T;Xu Y;Franzen R .[J].Cent Fur J Chem,2008,6:390.
[5] Suzuki A J .[J].Organometallic Chemistry,1999,576:147.
[6] Ito T.;Iwai T.;Mizuno T.;Ishino Y. .Palladium-catalyzed cross-coupling reaction of potassium diaryldifluoroborates with aryl halides[J].Synlett,2003(10):1435-1438.
[7] van der Boom M E;Milstein D .[J].Chemical Reviews,2003,103:1759.
[8] Littke A F;Fu G C .[J].Journal of the American Chemical Society,2001,123:6989.
[9] Hanhan M E .[J].Applied Organometallic Chemistry,2008,22:270.
[10] Morales-morales D;Redon R;Yung C;Jensen C M.[J].Chemical Communications,2000:1619.
[11] Feuerstein M;Laurenti D;Bougeant C;Doucet H,Santelli M.[J].Chemical Communications,2001:325.
[12] Trilla M;Borja G;Pleixats R;Man M W C Bied C Moreau J J E .[J].Advanced Synthesis and Catalysis,2008,350:2566.
[13] Yin L;Liebscher J .[J].Chemical Reviews,2007,107:133.
[14] Zheng Y;Stevens PD;Gao Y .Magnetic nanoparticles as an orthogonal support of polymer resins: Applications to solid-phase Suzuki cross-coupling reactions[J].The Journal of Organic Chemistry,2006(2):537-542.
[15] Zhou H;Zhou G L;Jiang X Z .[J].Journal of Molecular Catalysis A:Chemical,2006,248:26.
[16] 毛建忠,严新焕,顾辉子,江玲超.组合纳米Pt/C催化剂的邻氯硝基苯加氢性能[J].催化学报,2009(03):182-184.
[17] Dicenzo S B;Wertheim G K .[J].Solid State Physics Advances in Research and Applications,1985,11:203.
[18] Miyazaki A;Balint I;Aika K;Nakano Y .[J].Journal of Catalysis,2001,204:364.
[19] Marck G;Villiger A;Buchecker R .[J].Tetrahedron Letters,1994,35:3277.
[20] Pickett T E;Roca F X;Richards C T .[J].Journal of Organic Chemistry,2003,68:2595.
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