Benefits of donor solvents as additive on ROMP of norbornene catalyzed by amine Ru complexes
Benefits of donor solvents as additive on ROMP of norbornene catalyzed by amine Ru complexes
复制标题
供体溶剂作为胺钌配合物催化降冰片烯 ROMP 添加剂的优点
DOI：
10.1016/j.molcata.2005.07.003
复制
发表时间：
2005
影响因子：
--
通讯作者：
B. S. Lima
中科院分区：
文献类型：
--
作者：
J. M. E. Matos;B. S. Lima
为了了解给体溶剂对胺配合物[RuCl 2（PPh 3）2]反应活性的影响，（哌啶）]（1）和[RuCl 2（PPh 3）2（咪唑）2]（2）在重氮乙酸乙酯存在下，根据所得聚合物的性质，在少量常用溶剂如添加剂存在下，进行了异丙基苯的开环易位聚合（异丙醇、THF、N，N-二甲基甲酰胺、2，6-二甲基吡啶、异丙醚、乙腈、二甲亚砜、NEt 3、NH 2 Me和吡啶）。从观察，典型的配位溶剂，如DMSO，NEt 3，NH 2 Me和吡啶，几乎不影响产率时，任何一个配合物使用。使用其他添加剂，主要优点是多分散性指数降低。在使用配合物1与2，6-二甲基吡啶时，在纯溶液中在室温下保持10 - 1 min，观察到的Mw/Mn值低至1.3，而产率从99%降低至约20-30%。在对ROMP几乎无活性的络合物2（在50°C下5分钟为19%，Mw/Mn=6.30）的情况下，与没有THF的情况相比，产率为三倍（在50°C下5分钟为60%，Mw/Mn=1.95）。此外，观察到200当量的Mw/Mn降低至1.34。的THF。
With the aim of understanding the influence of donor solvents on the reactivity of the amine complexes [RuCl2(PPh3)2(piperidine)] (1) and [RuCl2(PPh3)2(imidazole)2] (2) in the presence of ethyldiazoacetate, and on the properties of the resulting polymer, a ring opening metathesis polymerization of norbornene was carried out in the presence of small amounts of common solvents such as additives (isopropanol, THF, N,N-dimethylformamide, 2,6-lutidine, isopropanethiol, acetonitrile, dimethyl sulfoxide, NEt3, NH2Me and pyridine). From observations, typical coordinating solvents like DMSO, NEt3, NH2Me and pyridine, hardly affected the yields when either complex was employed. With other additives, the major advantage was the decrease in the polydispersity indices. On using complex 1 with 2,6-lutidine, observed values of Mw/Mnwere as low as 1.3, while the yield decreased from 99% to about 20–30% at RT for ∼1min in pure solution. In the case of complex 2, which is almost inactive to ROMP (19% at 50°C for 5min with Mw/Mn=6.30), the yield was three-fold (60% at 50°C for 5min with Mw/Mn=1.95) compared to that of without THF. Further, the Mw/Mnwas observed to decrease to 1.34 with 200 eq. of THF.