低聚乙氧基醚链修饰的两亲性钯化合物及催化合成聚芴  

AMPHIPHATIC PALLADIUM COMPLEXES WITH POLYETHOXYLATED GROUPS AND THEIR APPLICATION IN SYNTHESIS OF POLY(9,9-DIOCTYFLUORENE)

作　　者：李静[1,2] 付宏伟[1,2] 胡盼[1,2] 张子龙[1] 李晓[1] 程延祥[1] 

机构地区：[1]中国科学院长春应用化学研究所,长春130022 [2]中国科学院大学,北京100039

出　　处：《高分子学报》2013年第9期1143-1150,共8页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21174141;51073152);国家重点基础研究发展计划(973计划;2009CB623600)资助

摘　　要：合成了一系列不同链长的双低聚乙氧基醚链修饰的三苯基膦,并以此为配体制备了相应的二价钯化合物.此类化合物在空气中具有良好稳定性,易溶于常用的有机溶剂.作为单组份催化剂,在无相转移试剂及无需补加膦配体条件下,能够有效催化Suzuki缩聚反应.在甲苯/水聚合体系中,可得到数均分子量(Mn)为7×104左右的聚芴.随着乙氧基醚链单元数的增加,Mn提高至近1×105.GPC谱图分析证实,亲水基团的引入使钯化合物具有了明显的两亲性,进而促进了金属转移步骤,使得聚合物分子量得以提高.A series of polyethoxylated amphiphatic palladium catalysts with two-chain polar head have been synthesized and applied in Suzuki polycondensation（SPC）,all of which are easy to dissolve in organic solvents for SPC（toluene,THF,DMF） and stable in atmospheric environment.Model polymer poly（9,9dioctylfluorene）（PFO） with M n = 7 × 104could be obtained using amphiphatic palladium catalysts with better hydrophilicity（Cp3 and Cm4） in toluene / H 2 O system,which were comparable to the results with addition of phase-transfer agent（Aliquat 336）.As the hydrophilicity of the amphiphatic catalysts got even stronger（Cp4）,higher molecular weight（M n ca.1 × 105） PFO could be achieved.From the GPC chromatograms for polymerization runs with different amphiphatic catalysts in toluene / water system,amphiphatic catalysts with longer polyethoxyl chain could be used to achieve higher molecular weight.And two peaks could be found in the GPC curves for polymerization runs with amphiphatic catalysts with strong enough hydrophilicity,which means there are high molecular portion and low molecular portion comprising the polymer product,indicating the process might follow two different reaction pathways.One is following the traditional way,base or the boronate anion in water phase are difficult to contact the oxidation addition intermediate in the organic phase,just resulting in low molecular weight polymers.The condition could be improved when the other way followed,the transmetalation step accelerated with the aid of the polyethoxyl chain anchoring to the two-phase interface,the catalytic cycle process could be improved and higher molecular weight polymers could be achieved.The bad performance of these neutral amphiphatic catalysts in THF / H 2 O and DMF / toluene indicates that the long polyethoxyl chain goes against the oxidation addition step in polar solvents,due to the rather good hydrophilicity of catalysts.

关 键 词：两亲性 钯化合物 Suzuki缩聚 聚芴 数均分子量 

分 类 号：O631.3[理学—高分子化学]