Synthesis and characterization of a novel catalyst based on dendrimer of core-POSS and its applications in epoxidation of olefins

5^th World Congress on Materials Science & Engineering

June 13-15, 2016 Alicante, Spain

E G Vieira and N L Dias Filho

Sao Paulo State University, Brazil

Posters & Accepted Abstracts: J Material Sci Eng

Abstract :

In this research we report the preparation and characterization of a new dendrimer of second-generation with a core of silsesquioxane (POSS-DG2.0). Polyhedral oligomeric silsesquioxanes (POSS), are nanoplatforms with one to eight reactive or nonreactive organofunctional groups (R) anchored to the eight possible vertices of the cubic silsesquioxane. In this nanomaterial was anchored six tungsten organometallic complexes ([W(CO)3Br2(NCMe)2]) for application in catalytic epoxidation of olefins. To the best of our knowledge, this study is the first that has reported the preparation of POSS-DG2.0-[W(CO)3Br2] for catalytic epoxidation of 1-octene, cyclooctene, (S)-limonene, cis-3-hexen-1-ol, trans-3-hexen-1-ol and styrene. The material was characterized using infrared spectroscopy, elemental analysis, solid-state 29Si and 13C nuclear magnetic resonance and scanning electronic microscope (SEM) coupled to an energy dispersive spectroscopy (EDS). The new organometallic nanomaterial POSS-DG2.0-[W(CO)3Br2] was tested as a catalyst in the epoxidation of 1-octene, cyclooctene, (S)-limonene, cis-3-hexen-1- ol, trans-3-hexen-1-ol and styrene. The catalyst behaved as an excellent catalytic precursor for the epoxidation of cyclooctene and styrene using TBHP (tert-butyl hydroperoxide). The material selectively catalyzed the epoxidation for the corresponding epoxides, with and without formation of diols depending on the substrate, with high conversions and TOFs. No reaction took place without a metal containing catalyst.

Biography :

Email: eduardo_vieira5007@yahoo.com.br