Montserrat Gómez

Supported ionic liquid phase catalysis on functionalized carbon nanotubes

Highly active rhodium catalysts have been prepared by immobilization of an ionic liquid film on carbon nanotubes functionalized with imidazolium-based ionic moieties.

Palladium catalyzed Suzuki C–C couplings in an ionic liquid: nanoparticles responsible for the catalytic activity

A new family of functionalized ligands derived from norborn-5-ene-2,3-dicarboxylic anhydride has been used in Suzuki C-C cross-couplings between aryl boronic acids and aryl bromide derivatives in [BMI][PF(6)] (BMI=1-n-butyl-3-methyl-imidazolium), using palladium acetate as catalytic precursor. High conversions and yields are obtained when amine ligands containing hydroxy groups are involved. TEM analyses after catalysis show the formation of small nanoparticles, in contrast to the agglomerates observed when nanoparticles are intentionally preformed, with a consequent decrease in the catalytic activity in the latter case. Some tests, including the correlation effect between solvent and ligand, are carried out to try to identify the true nature of the catalyst. All the results obtained suggest that formation of nanoparticles is required to lead to a catalytically active system.

Chiral diphospholes: III. Improved synthesis and coordination chemistry of (R,R)-DIPPOP

Abstract An improved, 90% yield synthesis of the chiral diphosphole, (R,R)-DIPPOP (1) is reported. The reactions of 1 with nickel, palladium, platinum and rhodium complexes are examined. 1 does not react with NiCl2. With PdCl2 and PtCl2 it forms various cis and trans diphosphine-bridged cyclooligomers of undetermined ring size. The rhodium complexes [Rh(cod)2]BF4, [Rh(acac) (cod)] and {Rh(μ-CI)(cod)}2 are good precursors for the synthesis of [Rh(cod){(R,R)-DIPPOP}]BF4, (8), [Rh(acac) {(R,R)-DIPPOP}],(9), and {Rh(cod)Cl}2{μ-P,P′-(R,R)-DIPPOP}, (10), which are fully characterized by multinuelear NMR spectroscopy.