Carboxyl Functionalized Ionic Liquids, Platinum Acetylene Synthesis And Catalytic Performance Of The Silicon Hydrogen Addition Reaction

In this paper, ionic liquids were introduced into the hydrosilylation reaction. Hyd-rosilylation of olefins catalyzed with rhodium complexes/carboxyl-functionalized im-idazolium salts had been studied. Both activity and selectivity of catalyst system cou Id be influenced by change the anion or cation structure of ionic liquids. The ratio of the β-adduct to the-adduct (β/a) is clearly increased with increasing length of alkyl ch ain attached to the pyridinium or imidazolium cations. It assumed that the counter ion-s of the ionic liquids used had some impact on the hydrosilylation reaction.Additionally, sulfur compounds were poison for the platinum catalyst, and signifi-cantly decreased the catalytic activity. This paper reported that a series of novel plati num-acetylide-phosphine complexes were synthesized. Platinum-acetylide-phosphine complexes showed high activity and were not poison in the existence of trace sulfur poisoning.1-Ethynylcyclohexanol and2-methylbut-3-yn-2-ol have been reported as inhibito-rs of platinum-catalyzed hydrosilylation. Triphenylphosphine is also a good hydrosily-lation inhibitor. On this basis, a series of novel platinum-acetylide-phosphine comple-xes had been synthesized, and these complexes exhibited little or no activity at low te-mperatures, but excellent cross-linking behavior at elevated temperatures for the curi-ng process of liquid silicon rubber.