An N-heterocyclic carbene ligand promotes highly selective alkyne semihydrogenation with copper nanoparticles supported on passivated silica

作者：Kaeffer Nicolas; Liu Hsueh Ju; Lo Hung Kun; Fedorov Alexey^*; Coperet Christophe^*

来源：Chemical Science, 2018, 9(24): 5366-5371.

DOI：10.1039/c8sc01924j

We report a surface organometallic route that generates copper nanoparticles (NPs) on a silica support while simultaneously passivating the silica surface with trimethylsiloxy groups. The material is active for the catalytic semihydrogenation of phenylalkyl-, dialkyl- and diaryl-alkynes and displays high chemo- and stereoselectivity at full alkyne conversion to corresponding (Z)-olefins in the presence of an N-heterocyclic carbene (NHC) ligand. Solid-state NMR spectroscopy using the NHC ligand C-13-labeled at the carbenic carbon reveals a genuine coordination of the carbene to Cu NPs. The presence of distinct Cu surface environments and the coordination of the NHC to specific Cu sites likely account for the increased selectivity.

• 出版日期2018-6-28