Tuning the Activity and Selectivity of Phenylacetylene Hydrosilylation with Triethylsilane in the Liquid Phase over Size Controlled Pt Nanoparticles

Dorina G. Dobó,Ákos Kukovecz,Dániel Sipos,Zoltán Kónya,Koppány Juhász,András Sápi,Gábor London

doi:10.3390/catal8010022

Dorina G. Dobó, Ákos Kukovecz + Show 5 more

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https://doi.org/10.3390/catal8010022

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Abstract

Pt nanoparticles with controlled sizes between 1.6–7.0 nm were anchored onto the surface and pores of SBA-15 silica support. The catalysts were characterized by TEM-ED, BET, XRD, and ICP-MS techniques and were tested in liquid phase hydrosilylation of phenylacetylene with triethylsilane. The activity of the 7.0 nm Pt nanoparticles anchored onto the surface of SBA-15 in hydrosilylation (TOF = 0.107 molecules·site−1·s−1) was ~2 times higher compared to the 5.0 nm Pt/SBA-15 (TOF = 0.049 molecules·site−1·s−1) catalyst and ~10 times higher compared to the 1.6 nm Pt/SBA-15 (TOF = 0.017 molecules·site−1·s−1) catalyst. Regarding the selectivity, bigger nanoparticles produced more vinylsilane-type products (α- and β-(E)-products) and less side products (mainly ditriethylsilane, triethyl(1-phenylethyl)silane and triethyl(phenethyl)silane derived likely from the reduction of the vinylsilane products). However, the selectivity towards the β-(E)-triethyl(styryl)silane was higher in the case of 1.6 nm Pt/SBA-15 catalyst compared to 5.0 nm Pt/SBA-15 and 7.0 nm Pt/SBA-15, respectively, which can be attributed to the beneficial effect of the size differences of the Pt nanoparticles as well as the differences of the quality and quantity of Pt/SiO2 interfaces.

Highlights

Organosilicon compounds obtained by hydrosilylation of unsaturated C-C-bonds are of great interest both from industrial and academic point of view [1]
We found that the activity of the 7.0 nm Pt nanoparticles anchored onto the surface of SBA-15
We found that the activity of the 7.0 nm Pt nanoparticles anchored onto the surface of SBA‐15 was ~2 times and ~10 times faster compared to 5.0 nm Pt/SBA-15 and 1.6 nm Pt/SBA-15, respectively

Summary

Introduction

Organosilicon compounds obtained by hydrosilylation of unsaturated C-C-bonds are of great interest both from industrial and academic point of view [1]. On one hand, they are the building blocks of several polymeric materials, while vinylsilanes derived from acetylenes are greener alternatives of organotin, organozinc, or organoboron compounds in transition metal catalyzed cross-coupling reactions [2]. Particles have been shown to beshown efficient Supported Pt [3,4,5,7,8,9,14],. Particles have been to heterogeneous hydrosylilation catalysts leading mostly to the β-(E)toproduct with high selectivity be efficient heterogeneous hydrosylilation catalysts leading mostly the β‐(E). Pt [3,4,5,7,8,9,14], Pd [13], Pd Pd alloys and[15,16], Au [6,10,12]

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