Selective Semihydrogenation of Alkynes with N-Graphitic-Modified Cobalt Nanoparticles Supported on Silica

Abstract

For the first time N-graphitic-modified cobalt nanoparticles (Co/phen@SiO 2 -800) are shown to be active in the semihydrogenation of alkynes to alkenes. Key to success for efficient catalysis is both the modification of the metal nanoparticles by nitrogen-doped graphitic layers and the use of silica as support. Several internal alkynes are converted to the Z isomer in high yields with up to 93% selectivity. In addition, a variety of terminal alkynes, including sensitive functionalized compounds, are readily converted into terminal alkenes. Notably, this non-noble-metal catalyst allows for the purification of alkenes by selective hydrogenation of the corresponding alkyne in the presence of an excess of olefin.

Intermetallic nickel silicide nanocatalyst—A non-noble metal–based general hydrogenation catalyst

“…The importance of nickel in the reduction process is shown by its comparison to supported cobalt nanoparticles used for selective semihydrogenation of alkynes ( 32 ). Although these cobalt catalysts were prepared in a similar fashion, formation of elemental silica and cobalt silicides was not observed.…”

Supported Cobalt Nanoparticles for Hydroformylation Reactions

“…[32,33] In the past years, our group has developeds everal nanoscale catalysts, especially based on N-doped carbon-supported cobalt and iron species. Those catalystsa re easily prepared by pyrolysis of ac arbon source,s uch as Vulcan XC 72R, impregnated with in situ ligatedCo [34,35] and Fe, [36,37] respectively.Similar materials containing nanoparticless upported on inorganic carriers [38] and biomass-derived catalysts werealso studied. [39][40][41] Based on these works, here we described the synthesis of cobalt-containing materials and studied their catalytic performance in hydroformylationr eactions.…”

Selective cobalt nanoparticles for catalytic transfer hydrogenation of N-heteroarenes

“…Recently, we 8 and other groups 9 developed new materials in which non-noble metal nanoparticles cooperatively interact with N-doped graphene and graphitic layers. 10 Due to this specific environment, these materials show excellent selectivity in several hydrogenation and oxidation reactions.…”