Rhodium Nanoflowers Stabilized by a Nitrogen-Rich PEG-Tagged Substrate as Recyclable Catalyst for the Stereoselective Hydrosilylation of Internal Alkynes

Morphology and size controllable rhodium nanoparticles stabilized by a nitrogen-rich polyoxyethylenated derivative have been prepared by reduction of RhCl₃ with NaBH₄ in water at room temperature and fully characterized. The flower-like Rh NPs are effective and recyclable catalysts for the stereoselective hydrosilylation of challenging internal alkynes and diynes, affording the (E)-vinylsilanes in quantitative yields for a wide range of substrates. The insolubility of the nanocatalyst in diethyl ether allows its easy separation and recycling.