Silveira Edson T, Umpierre Alexandre P, Rossi Liane M, Machado Giovanna, Morais Jonder, Soares Gabriel V, Baumvol Israel J R, Teixeira Sergio R, Fichtner Paulo F P, Dupont Jairton
Laboratory of Molecular Catalysis, Institute of Chemistry, UFRGS, Av. Bento Gonçalves, 9500 Porto Alegre 91501-970 RS, Brazil.
Chemistry. 2004 Aug 6;10(15):3734-40. doi: 10.1002/chem.200305765.
The controlled decomposition of an Ru(0) organometallic precursor dispersed in 1-n-butyl-3-methylimidazolium hexafluorophosphate (BMI.PF(6)), tetrafluoroborate (BMI.BF(4)) or trifluoromethane sulfonate (BMI.CF(3)SO(3)) ionic liquids with H(2) represents a simple and efficient method for the generation of Ru(0) nanoparticles. TEM analysis of these nanoparticles shows the formation of superstructures with diameters of approximately 57 nm that contain dispersed Ru(0) nanoparticles with diameters of 2.6+/-0.4 nm. These nanoparticles dispersed in the ionic liquids are efficient multiphase catalysts for the hydrogenation of alkenes and benzene under mild reaction conditions (4 atm, 75 degrees C). The ternary diagram (benzene/cyclohexene/BMI.PF(6)) indicated a maximum of 1 % cyclohexene concentration in BMI.PF(6), which is attained with 4 % benzene in the ionic phase. This solubility difference in the ionic liquid can be used for the extraction of cyclohexene during benzene hydrogenation by Ru catalysts suspended in BMI.PF(6). Selectivities of up to 39 % in cyclohexene can be attained at very low benzene conversion. Although the maximum yield of 2 % in cyclohexene is too low for technical applications, it represents a rare example of partial hydrogenation of benzene by soluble transition-metal nanoparticles.
将分散于六氟磷酸1-正丁基-3-甲基咪唑鎓（BMI.PF(6)）、四氟硼酸（BMI.BF(4)）或三氟甲磺酸（BMI.CF(3)SO(3)）离子液体中的Ru(0)有机金属前驱体与H(2)进行受控分解，是一种生成Ru(0)纳米颗粒的简单有效方法。对这些纳米颗粒的透射电子显微镜（TEM）分析表明，形成了直径约为57 nm的超结构，其中包含直径为2.6±0.4 nm的分散Ru(0)纳米颗粒。这些分散在离子液体中的纳米颗粒是在温和反应条件（4个大气压，75℃）下用于烯烃和苯氢化的高效多相催化剂。三元图（苯/环己烯/BMI.PF(6)）表明，在BMI.PF(6)中，环己烯浓度最高为1%，这是在离子相中含有4%苯时实现的。离子液体中的这种溶解度差异可用于在BMI.PF(6)中悬浮的Ru催化剂催化苯氢化过程中提取环己烯。在非常低的苯转化率下，环己烯的选择性可达39%。尽管环己烯2%的最大产率对于工业应用来说太低，但它代表了可溶性过渡金属纳米颗粒对苯进行部分氢化的一个罕见例子。
