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Platinum
(0) Mesitylene
in mesitylene
solution (Stabilized
by vinylsiloxanes)
Ptn
nanoparticles ranging 0.5 - 1 nm, as evidenced by TOF-MS analysis
Excellent catalyst for hydrosilylation reactions
Excellent
precursors for the deposition of Pt nanoparticles on C or solid oxide supports
J.
Organomet. Chem., 451 (1993) C4;
J. Mol. Catal., 91 (1994) 83
Rhodium
Mesitylene in mesitylene solution
Rhodium
THF
in THF solution (Stabilized
by trioctylamine (TOA))
Rhn
nanoclusters ranging 0.5 1 nm in diameter
Active in hydrogenation, hydroformylation and
hydrosilylation reactions
Excellent
precursors for the deposition of activated Rh particles,ranging 1 2 nm in
diameter, on C or solid oxide supports.
metal Vapour when reacting with weakly stabilizing
ligand (solvent) at low temperature gives the product of Solvated metal Atoms
containing metal microclusters stabilized by the solvent.
Palladium
(0) Mesitylene in mesitylene solution
(Stabilized
by TOA)
Pdn
nanoparticles ranging 0.5 - 1 nm
Active in Heck reactions
Suitable
for the deposition of active Pd nanoparticles, ranging 1 2 nm in diameter,
on C or solid oxide supports
Metal catalysts
presently available
Homogeneous
Catalysts
Co
(0) Toluene in
toluene solution
(Stabilized
by 2-butyne) Con microclusters, (n ≤ 10) as evidenced by EPR
Active in the cyclococyclization of alkynes and nitriles;it has been proved successful even in hydroformylation reaction.
Suitable
for the deposition of activated Co particles, ranging 2 3 nm in diameter, on
C or solid oxide supports.
J.
Mol. Catal., 56 (1989) 133.
An
example of the catalytic activity and selectivity of Homogeneous catalysts:
Idrosilylation
of vinyl compounds with a Pt-mesitylene solution obtained via MVS technique.
In
analogous conditions a Pt Karstedt catalyst does not catalyse the reaction.
Solvated metal Atoms can be used as homogeneous
catalytic precursors and as a source of active metal nanoparticles to produce
supported and unsupported catalysts (Scheme).
Fe(0)
Cycloolefins in
aliphatic solvents
Active catalysts for the cyclotrimerization of
alkynes and for hydroformylation reactions
Suitable
for the deposition of active Fe nanoparticles on solid supports and for the
preparation of magneto fluids
Au
(0) Acetone in
acetone solution
Aun
microclusters (n<10) stabilized by acetone; as shown by
TOF-MS analyses
Active catalysts in oxygenation reactions with
molecular oxygen
9Th
FECS Conference, Bordeaux (F), 2004 29 August 1 September, Abstract p.353
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