Weakly-coordinated stable platinum nanocrystals
by Dorothea Marquardt, Juri Barthel, Markus Braun, Christian Ganter and Christoph Janiak
Stable platinum nanocrystals with small diameters (1.0-2.3 nm), that are stable for a long time, with narrow size distributions were easily and reproducibly prepared without any additional stabilisers in glycol, glycerol, the ionic liquids (ILs) 1-n-butyl-3-methyl-imidazolium tetrafluoroborate [BMIm][BF4] and N-butyl-N-trimethyl-ammonium bis(trifluoromethylsulfonyl)imide [N4111][NTf2] or diphenylmethane (CH2Ph2) by thermal, photolytic or microwave assisted decomposition of the organometallic precursor methylcyclopentadienyl-trimethylplatinum(IV), (MeCp)PtMe3. Decomposition of the easily dispensible, air and moisture stable organometallic Pt(IV) precursor (MeCp)PtMe3 leads to well defined, small, crystalline and longterm stable Pt-nanoparticle (Pt-NP) dispersions without any additional surface-capping ligands. The Pt-NP/IL dispersion was shown to be a highly active catalyst (TOF 96000 h"1 at 0.0125 mol% Pt and quantitative conversion) for the biphasic hydrosilylation of phenylacetylene with triethylsilane, to the distal and proximal products triethyl(2- and1-phenylvinyl)silane.
Dorothea Marquardt, Juri Barthel, Markus Braun, Christian Ganter and Christoph Janiak: Weakly-coordinated stable platinum nanocrystals, CrystEngComm 14 (2012) 7607-7615.