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Your search keyword '"de Bruin, B."' showing total 5 results
Start Over Author "de Bruin, B." Journal european journal of inorganic chemistry
5 results on '"de Bruin, B."'

1. Allylpalladium(II) Histidylidene Complexes and Their Application in Z-Selective Transfer Semihydrogenation of Alkynes

Author

Drost, Ruben M., Broere, Daniël L J, Hoogenboom, Jorin, de Baan, Simone N., Lutz, Martin, de Bruin, B., Elsevier, C. J., Sub Crystal and Structural Chemistry, Crystal and Structural Chemistry, Homogeneous and Supramolecular Catalysis (HIMS, FNWI), and Molecular Inorganic Chemistry (HIMS, FNWI)

Subjects
chemistry.chemical_classification, Substituent, chemistry.chemical_element, Homogeneous catalysis, Combinatorial chemistry, Palla-dium, Catalysis, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Alkynes, Carbenes, Imidazole, Organic chemistry, Hydrogenation, Carbene, Alkyl, Histidine, Reduction, Palladium
Abstract

We have studied the use of amino acid histidine as a precursor for N-heterocyclic carbene (NHC) ligands. This natural amino acid possesses an imidazole substituent, which makes it an interesting NHC precursor that contains both an acid and an amino functionality. These functionalities may be used for further tuning of NHC complexes. We have developed routes for the synthesis of symmetric and dissymmetric alkyl, benzyl, and aryl-substituted histidinium salts. Subsequently, the corresponding Ag and Pd histidylidenes were synthesized and the palladium complexes were tested in the Z-selective transfer semihydrogenation of alkynes. Histidylidene palladium complexes that contain additional donor functionalities were found to display good selectivities. The best catalytic results were obtained with a Pd-histidylidene complex that contains two picolyl functional groups.

Published
2015

2. Synthesis and Reactivity of Ester‐Functionalized 5‐Membered Rh I ‐κ 2 ‐C,O‐Chelates and Their Relevance in Rh(cod)‐Mediated Carbene Polymerization

Author

Finger, M., Lutz, M., Reek, J.N.H., de Bruin, B., Rontgen participation programme, Sub Crystal and Structural Chemistry, and Homogeneous and Supramolecular Catalysis (HIMS, FNWI)

Subjects
Olefin fiber, Diene, 010405 organic chemistry, Chemistry, Ligand, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, Rhodium, Inorganic Chemistry, chemistry.chemical_compound, Polymerization, Organic chemistry, Reactivity (chemistry), Carbene, Group 2 organometallic chemistry
Abstract

The previous mechanistic studies of the Rh-mediated polymerization of carbenes suggests the involvement of organometallic compounds that have been derived from Rh(diene) species that contain a five-membered chelate ring of the type Rh{κ2-C,O-[-CH(COOR)-CH(Pol)-C(OR)=O-]} (Pol = polymer chain), which are characterized by the coordination of the β-ester group of the growing polymer chain to the metal. Herein we present our efforts to characterize the possibly related RhI(cod){κ2-C,O-[-CH(COOR)-CHR′-C(OR)=O-]} (cod = 1,5-cyclooctadiene) species. These structures can be generated by means of olefin exchange with an allyl complex and with the concomitant release of the corresponding 1,3-diene, which is derived from the allyl ligand. The product is unstable and further reacts by means of a bimolecular C-H activation process to form a related dinuclear complex [(cod)Rh(μ-{-CH(COOR)-CH-C(OR)=O-})2Rh(cod)], in which the carbon dianion of the dimethyl or diethyl succinate bridges two Rh(cod) moieties. The complex was synthesized in an independent way and was structurally characterized. We investigated the importance of these complexes in carbene polymerization.

Published
2011
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3. Ureaphosphanes as hybrid, anionic or supramolecular bidentate ligands for asymmetric hydrogenation reactions

Author

Meeuwissen, J., Detz, R., Sandee, A. J., de Bruin, B., Siegler, M. A., Spek, A.L., Reek, J.N.H., Crystal and Structural Chemistry, Sub Crystal and Structural Chemistry, Homogeneous and Supramolecular Catalysis (HIMS, FNWI), Crystal and Structural Chemistry, and Sub Crystal and Structural Chemistry

Subjects
chemistry.chemical_classification, Denticity, Chemistry, Ligand, Asymmetric hydrogenation, Supramolecular chemistry, Cationic polymerization, Medicinal chemistry, Coordination complex, Inorganic Chemistry, chemistry.chemical_compound, Organic chemistry, Chelation, Acetamide
Abstract

We report the coordination behavior of ureaphosphane ligand 1[2-(diphenylphosphanyl)ethyl]-3-phenylurea (L1) towards different rhodium precursor complexes. Depending on the nature of the anion and the ligand/metal ratio, L1 acts either as a hybrid P, O-coordinating chelate, as an anionic P,N-coordinating chelate or as a supramolecular (hydrogen-bonded) bidentate ligand. The different types of complexes were investigated in the asymmetric hydrogenation of three olefinic substrates using ureaphosphanes L2 and L3, which are chiral analogues of L1. For methyl 2-acetamidoacrylate (Si) and dimethyl itaconate (S2) the neutral complex [Rh(L2-kappa P-2,N)(cod)], containing an anionic RN-coordinating ureaphosphane ligand, provided the best enantioselectivity (69.2 and 24.3 %, respectively). For N-(3,4-dihydro-2-naphth-alenyl)acetamide (S3) the best enantioselectivity was obtained with the cationic complex [Rh(L3-kappa P-2,O)(nbd)]BF4, containing a hybrid PO-coordinating ureaphosphane ligand (86.1 %).

Published
2010

4. Nickel-Alkyl Complexes with a Reactive PNC-Pincer Ligand.

Author

Jongbloed LS, Vogt N, Sandleben A, de Bruin B, Klein A, and van der Vlugt JI

Abstract

Based on previous work related to the design and application of rigid tridentate phosphine-pyridine-phenyl coordination offered by a PNC-pincer ligand upon cyclometalation to nickel, the synthesis, spectroscopic and solid state characterization and redox-reactivity of two Ni II (PNC) complexes featuring either a methyl ( 2CH 3 ) or CF 3 co-ligand ( 2CF 3 ) are described. One-electron oxidation is proposed to furnish C-C reductive elimination, as deduced from a combined chemical, electrochemical, spectroscopic and computational study. One-electron reduction results in a ligand-centered radical anion, as supported by electrochemistry, UV spectroelectrochemistry, EPR spectroscopy, and DFT calculations. This further attenuates the breadth of chemical reactivity offered by such PNC-pincer ligands.

Published
2018
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5. Coordination of 3-Methylindole-Based Tripodal Tetraphosphine Ligands to Iron(+II), Cobalt(+II), and Nickel(+II) and Investigations of their Subsequent Two-Electron Reduction.

Author

van de Watering FF, Stroek W, Ivar van der Vlugt J, de Bruin B, Dzik WI, and Reek JNH

Abstract

We report the coordination chemistry of indole based tripodal tetraphosphine ligands to iron(II), cobalt(II) and nickel(II). These complexes are formed by simple synthetic protocols and were characterized by a combination of spectroscopic techniques and single-crystal X-ray analysis. The molecular structures as determined by X-ray diffraction show that the geometry of the nickel and cobalt complexes are distorted trigonal bipyramidal. The monocationic iron(II) complexes also have distorted trigonal bipyramidal geometries, but the dicationic analogue has an octahedral geometry. Two-electron reduction of the cobalt(+II) and the nickel(+II) complexes in the presence of N 2 did not lead to the coordination of N 2 . In contrast, two-electron reduction of the iron(+II) complexes did lead to coordination of dinitrogen to the iron center. The Fe 0 N 2 L1 H complex has a trigonal bipyramidal geometry, and the N-N bond length of the coordinated dinitrogen ligand is longer than that of free dinitrogen, indicating that coordination to this iron(0) complex results in activation of the N≡N bond.

Published
2018
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