Departament de Química Física i Inorgànica Grup de Catálisi Homogènia i Síntesi Orgánica Estereoselectiva 2001 SGR 00316 Prof. Carmen Claver Organometál.lics i Catàlisi Homogénia OMICH Prof. Sergio Castillón Síntesis Orgánica Departament de Química Análitica I Química Orgánica
Grup de Catálisi Homogènia i Síntesi Orgánica Estereoselectiva 2001 SGR 00316. Prof. Sergio Castillón Síntesis Orgánica. Departament de Química Análitica I Química Orgánica. Prof. Carmen Claver Organometál.lics i Catàlisi Homogénia OMICH. Departament de Química Física i Inorgànica. - PowerPoint PPT Presentation
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Departament de Química Física i Inorgànica
Grup de Catálisi Homogènia i Síntesi Orgánica Estereoselectiva
2001 SGR 00316
Prof. Carmen ClaverOrganometál.lics i Catàlisi HomogéniaOMICH
Prof. Sergio CastillónSíntesis Orgánica
Departament de Química Análitica I Química Orgánica
Metallic nanoparticles as catalyst
Hydrogenation Hydrosilylation
Oxidation C-C coupling reactions
N
HO N Chem. Eur. J., 1997, 3, 1200Tetrahedron Lett. 1998, 39, 1941
“Probing Catalysis on the Nanoscale” Science & Technology, C&EN,September 27,2004
-Only one example in enantioselective catalyst
-High activity and selectivity (large specific surface)
-Activity in reactions where other catalysts are not active
-Efficient catalysts for several proceses
Metallic nanoparticles stabilized by organic ligands
Stabilisation and reproducibility.
Control of nanoparticles.
Uniformity in particle size, composition and morphology.
Systematic modification of the ligands: Effect on the properties of the nanoparticles.
Organometallic complexes as starting materials.
NANOCATALYST
Metal Nanoparticles Stabilized by Organic Ligands. Applications in Catalysis
Synthesis of nanoparticles of transition metals stabilized by organic ligands:
-Perfluorinated ligands.
Application in hydrogenation reaction.
-Chiral ligands with carbohydrate backbone.
Application C-C coupling reactions
-Synthesis of pyridine derivative perfluorinated ligands
-Metal nanoparticles stabilization of different transition metals
-Application as catalyst for arene hydrogenation in supercritic CO2
1. Synthesis of nanoparticles of transition metals stabilized by organic ligands.
Application in hydrogenation reaction
N
C8F17(CH2)4
N
C8F17(CH2)4
N
C8F17(CH2)4
N
C8F17(CH2)4
CH3-(CH2)15-NH2
Ph2P-(CH2)10-PPh2
PhP(-(CH2)2-PPh2)2
(a)
(b)
(HDA)
[Pd(C3H5)Cl]2
Ligand
3 bar H2; r.t.; 20h
THF or Toluene
[Pd/Ligand]0or
Ligands: CH3-(CH2)15-NH2
Ph2P-(CH2)10-PPh2
PhP(-(CH2)2-PPh2)2
Pd nanoparticles
Pd2(dba)3
Influence of Organic Ligands on the Stabilization Organometallic Palladium Nanoparticles. E. Ramirez, S. Jansat, K. Philippot, P. Lecante, M. Gomez, A.Masdeu, B. ChaudretJ. Organomet. Chem. 2004, (submitted)
-Design and synthesis of new carbohydrate ligands
-Synthesis and characterization of metal nanoparticles(Rh,Pd, Ru) with new chiral ligands
-Application in palladium catalyzed C-C bond reactions and other catalytic processes.
2. Metal nanoparticles stabilized by organic chiral ligands with carbohydrate
backbone.
OO
OOO
PO
O
P
O
O
OPh2P
OOPh2P
Ph2P
OOO
P
O
O
O
[Pd2(dba)3] [Pdx(dba)y(THF)zLw] dba-H2
3 bar H2
L, THF+
OO
OO
OPP
O
OO
O
tBu
But
But tBuBut
tBu
tBu
tBu
A case for Enantioselective Allylic Alkylation Catalyzed by Palladium NanoparticlesS.Jansat,M. Gomez, K. Philippot, G.Muller, E. Guiu, C. Claver, S. Castillón, B. ChaudretJ. Am. Chem. Soc., 2004, 126, 1593
Synthesis of palladium nanoparticles
L=
Ph Ph
OAcH2C(COOMe)2
Ph Ph
CH(COOMe)2
BSA, KOAcCH2Cl2, rt
[Pd/L*]
+
IIrac-I
Catalyst I / Pd/ L* Time (h)
Conv. (% )
ee I I (% )
ee I (% )
Coll.1 100/1/0.2 24 56 94 (S) 92 (S)
Coll.1 100/1/0.2 168 59 94 (S) 98 (S)
Mol.1 100/1/1.25 1.5 83 90 (S) 0
Catalysis. Reaction of allylic alkylation
-Homogeneous catalyst and nanocatalyst behave differently-First example of kinetic resolution with nanocatalyst